electroporation-hindbrain-to-trace-axonal-trajectories-synaptic

Electroporation of the Hindbrain to Trace Axonal Trajectories and Synaptic Targets in the Chick Embryo

Electroporation of  the chick embryonic neural tube has many advantages such as being quick and efficient  for the expression of foreign genes into ...

The Hebrew University of Jerusalem

BMP4 &#x53CA;&#x5176;&#x6291;&#x5236;&#x5242;&#x3001; &#x8111;&#x888B;&#xFF0C;&#x4E4B;&#x95F4;&#x7684;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x89C4;&#x7BA1; somites &#x548C;&#x795E;&#x7ECF;&#x5D74;&#x7684;&#x9635;&#x5217;&#x3002;&#x5728;&#x4E2D;&#x80DA;&#x5C42;&#x53D1;&#x5C55;&#xFF0C;mRNA &#x8868;&#x793A;&#x5728;&#x4E2D;&#x95F4;&#x7684;&#x4E2D;&#x80DA;&#x5C42;&#x7684;&#x8111;&#x888B;&#x3002;&#x540E;&#x5206;&#x5272;&#xFF0C;&#x5B83;&#x88AB;&#x68C0;&#x6D4B;&#x4E0A;&#x76AE; somites &#x9010;&#x6B65;&#x6210;&#x4E3A; medialized &#x4F5C;&#x4E3A;&#x4ED6;&#x4EEC;&#x6210;&#x719F;&#x7684;&#x5916;&#x4FA7;&#x90E8;&#x5206;&#x3002;&#x5728;&#x6E38;&#x79BB;&#x7684;&#x7EC6;&#x5206;&#xFF0C;&#x8111;&#x888B;&#x53D8;&#x5F97;&#x77ED;&#x6682;&#x9650;&#x4E8E;&#x80CC;&#x5507;&#x7684; dermomyotome&#x3002;&#x5728;&#x8FD9;&#x91CC;&#xFF0C;&#x6211;&#x4EEC;&#x8C03;&#x67E5;&#x4E86; factor(s)&#xFF0C;&#x63A7;&#x5236;&#x8F6C;&#x5F55;&#x7684; somitic &#x8111;&#x888B;&#x8FD9;&#x4FA7;&#x7684;&#x5185;&#x4FA7;&#x7684;&#x8F6C;&#x53D8;&#x3002;&#x5728;&#x9AB6;&#x7BA1;&#x5916;&#x4FA7;&#x677F;/&#x4E2D;&#x95F4;&#x4F53;&#x4E2D;&#x80DA;&#x5C42;&#x4E2D;&#x9AA8;&#x5F62;&#x6001;&#x53D1;&#x751F;&#x86CB;&#x767D;&#x6D3B;&#x6027;&#x7684;&#x6291;&#x5236;&#x4F5C;&#x7528;&#x963B;&#x6B62;&#x8111;&#x888B;&#x8F6C;&#x5F55;&#x7684;&#x5916;&#x4FA7;&#x4F53;&#x8282;&#x3002;&#x8FDB;&#x4E00;&#x6B65; rostrally &#xFF08;&#x6216;&#x66F4;&#x9AD8;&#x7248;&#x672C;&#x4E2D;&#x53D1;&#x5C55;&#xFF09;&#xFF0C;&#x6291;&#x5236; Wnt &#x6D3B;&#x52A8;&#x7BA1;&#x6D3E;&#x751F; BMP&#xFF0C;&#x4F46;&#x4E0D;&#x662F;&#x59A8;&#x788D;&#x521D;&#x59CB;&#x8111;&#x888B;&#x8868;&#x8FBE;&#x5F0F;&#x4E2D;&#x80CC;&#x5507;&#x7684; dermomyotome&#x3002;&#x6B64;&#x5916;&#xFF0C;BMP4 &#x662F;&#x4E0D;&#x8DB3;&#x4EE5;&#x89E6;&#x53D1;&#x751A;&#x81F3;&#x5728;&#x5916;&#x80DA;&#x5C42;&#x548C;/&#x6216;&#x795E;&#x7ECF;&#x7BA1;&#xFF0C;&#x6CA1;&#x6709;&#x8111;&#x888B;&#x7684;&#x521D;&#x59CB;&#x8868;&#x8FBE;&#x5EFA;&#x8BAE;&#x80CC;&#x4F53;&#x8282;&#x4E0A;&#x7684;&#x76F4;&#x63A5;&#x884C;&#x52A8;&#x3002;&#x56E0;&#x6B64;&#xFF0C;somites &#x8111;&#x888B;&#x8F6C;&#x5F55;&#x7684;&#x6A21;&#x5F0F;&#x662F;&#x76F4;&#x63A5;&#x53D7; BMP4 &#x6D3B;&#x52A8;&#x9996;&#x5148;&#x6765;&#x81EA;&#x4E2D;&#x80DA;&#x5C42;&#x548C;&#x4EE5;&#x540E;&#x4ECE;&#x795E;&#x7ECF;&#x7BA1;&#x3002;BMP4 &#x548C; IA &#x578B;&#x9AA8;&#x5F62;&#x6210;&#x86CB;&#x767D;&#x53D7;&#x4F53;&#x7684;&#x8868;&#x8FBE;&#x6A21;&#x5F0F;&#x90FD;&#x4E0E;&#x8FD9;&#x4E00;&#x4FA7;&#x7684;&#x5185;&#x4FA7;&#x8F6C;&#x53D8; spatiotemporally &#x517C;&#x5BB9;&#x3002;&#x8FD9;&#x4E9B;&#x7ED3;&#x679C;&#x7A81;&#x51FA;&#x663E;&#x793A;&#x795E;&#x7ECF;&#x7BA1;&#x7684;&#x4E2D;&#x80DA;&#x5C42;&#x590D;&#x5408;&#x4F53;&#x7684; BMP &#x79EF;&#x6781;&#x8C03;&#x8282;&#x8F6C;&#x5F55;&#x7684;&#x8111;&#x888B;&#xFF0C;&#x8FD9;&#x53CD;&#x8FC7;&#x6765;&#x538B;&#x8FEB;&#x8FDB;&#x4E00;&#x6B65;&#x914D;&#x4F53;&#x6D3B;&#x52A8;&#x7684;&#x89C4;&#x7BA1;&#x5FAA;&#x73AF;&#x4E2D;&#x5B58;&#x5728;&#x3002;

&#x672C;&#x5730;&#x5316;&#x7684; BMP4 &#x8111;&#x888B;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x5728; somites &#x4E2D;&#x751F;&#x6210;&#x52A8;&#x6001;&#x53D1;&#x751F;&#x7684;&#x8111;&#x888B;&#x8868;&#x8FBE;&#x683C;&#x5C40;&#x3002;

Interactions between BMP4 and its inhibitor, noggin, regulate patterning of somites and neural crest. During mesoderm development, noggin mRNA is expressed in the intermediate mesoderm. Upon segmentation, it is detected in the lateral portion of epithelial somites becoming progressively medialized as they mature. In dissociated segments, noggin becomes transiently confined to the dorsomedial lip of the dermomyotome. Here, we investigated the factor(s) that control this lateral-to-medial shift in transcription of somitic noggin. Inhibition of BMP activity in the caudal lateral plate/intermediate mesoderm prevented noggin transcription in the lateral somite. Further rostrally (or later in development), inhibition of tube-derived BMP, but not of Wnt activity, prevented initial noggin expression in the dorsomedial lip of the dermomyotome. Moreover, BMP4 was sufficient to trigger initial expression of noggin even in the absence of ectoderm and/or neural tube, suggesting a direct action on the dorsomedial somite. Thus, the patterns of noggin transcription in somites are directly regulated by BMP4 activities emanating first from the mesoderm and later from the neural tube. Expression patterns of BMP4 and of type IA BMP receptors are spatiotemporally compatible with this lateral-to-medial shift. These results highlight the existence in the neural tube-mesoderm complex of a regulatory loop by which BMP positively regulates transcription of noggin, which in turn represses further ligand activity.

Localized BMP4-noggin interactions generate the dynamic patterning of noggin expression in somites.

Les interactions entre BMP4 et de son inhibiteur, noggin, de r&#xE9;glementer la structuration de somites et de la cr&#xEA;te neurale. Au cours du d&#xE9;veloppement du m&#xE9;soderme, l&#x26;#39;ARNm de noggine est exprim&#xE9;e dans le m&#xE9;soderme interm&#xE9;diaire. Sur la segmentation, il est d&#xE9;tect&#xE9; dans la partie lat&#xE9;rale des somites &#xE9;pith&#xE9;liaux se sont progressivement medialized &#xE0; mesure qu&#x26;#39;ils vieillissent. Dans les segments dissoci&#xE9;s, noggin devient transitoirement limit&#xE9; &#xE0; la l&#xE8;vre dorsom&#xE9;dial de l&#x26;#39;dermomyotome. Ici, nous avons &#xE9;tudi&#xE9; le facteur (s) qui contr&#xF4;lent ce d&#xE9;placement lat&#xE9;ral &#xE0; m&#xE9;dial dans la transcription de la caboche somitique. L&#x26;#39;inhibition de l&#x26;#39;activit&#xE9; dans le BMP caudale lat&#xE9;rale plaque / interm&#xE9;diaire m&#xE9;soderme emp&#xEA;ch&#xE9; la transcription noggine dans le somite lat&#xE9;rale. En outre rostrale (ou plus tard dans le d&#xE9;veloppement), l&#x26;#39;inhibition du tube d&#xE9;riv&#xE9; BMP, mais pas d&#x26;#39;activit&#xE9; Wnt, emp&#xEA;ch&#xE9; l&#x26;#39;expression noggin initiale dans la l&#xE8;vre de la dorsom&#xE9;dial dermomyotome. En outre, BMP4 &#xE9;tait suffisante pour d&#xE9;clencher l&#x26;#39;expression initiale de noggin m&#xEA;me en l&#x26;#39;absence de l&#x26;#39;ectoderme et / ou du tube neural, ce qui sugg&#xE8;re une action directe sur le somite dorsom&#xE9;dial. Ainsi, les mod&#xE8;les de la transcription dans les somites sont noggin directement r&#xE9;glement&#xE9;e par BMP4 activit&#xE9;s &#xE9;manant d&#x26;#39;abord de le m&#xE9;soderme et plus tard &#xE0; partir du tube neural. Profils d&#x26;#39;expression de BMP4 et des r&#xE9;cepteurs de type BMP IA sont spatio-temporelle compatible avec ce d&#xE9;calage lat&#xE9;ral &#xE0; m&#xE9;dial. Ces r&#xE9;sultats mettent en &#xE9;vidence l&#x26;#39;existence dans le tube neural-m&#xE9;soderme complexe d&#x26;#39;une boucle de r&#xE9;gulation par lequel BMP r&#xE9;gule positivement la transcription de caboche, qui &#xE0; son tour r&#xE9;prime l&#x26;#39;activit&#xE9; ligand plus loin.

Localis&#xE9;es BMP4-caboche interactions produisent la structuration dynamique de l&#x26;#39;expression Noggin dans les somites

Lokalisierte BMP4-Birne Interaktionen erzeugen die dynamische Strukturierung von Noggin-Expression in Somiten.

Interazioni tra BMP4 e suo inibitore, noggin, regolano patterning di somiti e cresta neurale. Durante lo sviluppo mesoderma, noggin mRNA &egrave; espresso nel mesoderma intermedio. Sulla segmentazione, si &egrave; rilevato nella parte laterale dei metameri epiteliali progressivamente diventando medialized Man mano che maturano. Nei segmenti dissociate, zucca diventa transitoriamente confinata al labbro dorsomedial della dermomyotome. Qui, abbiamo studiato il fattore (fattori) che controllano questo spostamento laterale-mediale nella trascrizione di zucca somitic. Inibizione dell&#39;attivit&agrave; BMP in mesoderma caudale piastra laterale ed intermedi impedito trascrizione zucca nel somite laterale. Ulteriore rostralmente (o pi&ugrave; tardi in via di sviluppo), inibizione di BMP derivato da tubo, ma non di attivit&agrave; di Wnt, impedito espressione iniziale noggin nel labbro dorsomedial della dermomyotome. Inoltre, BMP4 era sufficiente a innescare l&#39;espressione iniziale di zucca anche in assenza dell&#39;ectoderma e/o tubo neurale, suggerendo un&#39;azione diretta sul somite dorsomedial. Cos&igrave;, i modelli della trascrizione di zucca in somiti direttamente sono regolamentati dalle attivit&agrave; BMP4 che emana innanzitutto dal mesoderma e successivamente dal tubo neurale. I modelli di espressione di BMP4 e dei recettori BMP di tipo IA sono spatiotemporally compatibili con questo spostamento laterale-mediale. Questi risultati evidenziano l&#39;esistenza nel complesso tubo neurale-mesoderma di un ciclo normativo da cui BMP regola positivamente trascrizione della zucca, che a sua volta reprime ulteriore attivit&agrave; di ligando.

Localizzate le interazioni BMP4-zucca a generare il patterning dinamica dell&#39;espressione noggin somiti.

BMP4&#x304A;&#x3088;&#x3073;&#x305D;&#x306E;&#x963B;&#x5BB3;&#x5264;&#x3001;noggin&#x306E;&#x9593;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x306F;&#x3001;&#x4F53;&#x7BC0;&#x3068;&#x795E;&#x7D4C;&#x5824;&#x306E;&#x30D1;&#x30BF;&#x30FC;&#x30CB;&#x30F3;&#x30B0;&#x3092;&#x5236;&#x5FA1;&#x3057;&#x3066;&#x3044;&#x308B;&#x3002;&#x4E2D;&#x80DA;&#x8449;&#x306E;&#x958B;&#x767A;&#x4E2D;&#x306B;&#x3001;&#x982D;&#x306E;mRNA&#x306F;&#x3001;&#x4E2D;&#x9593;&#x4E2D;&#x80DA;&#x8449;&#x306B;&#x767A;&#x73FE;&#x3057;&#x3066;&#x3044;&#x308B;&#x3002;&#x30BB;&#x30B0;&#x30E1;&#x30F3;&#x30C6;&#x30FC;&#x30B7;&#x30E7;&#x30F3;&#x6642;&#x306B;&#x3001;&#x305D;&#x308C;&#x306F;&#x5F7C;&#x3089;&#x304C;&#x6210;&#x719F;&#x3059;&#x308B;&#x3088;&#x3046;&#x306B;&#x5F90;&#x3005;&#x306B;medialized&#x306B;&#x306A;&#x308B;&#x4F53;&#x7BC0;&#x4E0A;&#x76AE;&#x306E;&#x5916;&#x5074;&#x90E8;&#x3067;&#x691C;&#x51FA;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x89E3;&#x96E2;&#x30BB;&#x30B0;&#x30E1;&#x30F3;&#x30C8;&#x3067;&#x306F;&#x3001;&#x982D;&#x3067;&#x306F;&#x4E00;&#x904E;&#x6027;dermomyotome&#x306E;&#x80CC;&#x5185;&#x5074;&#x5507;&#x306B;&#x9650;&#x5B9A;&#x3068;&#x306A;&#x308A;&#x307E;&#x3059;&#x3002;&#x3053;&#x3053;&#x3067;&#x306F;&#x3001;&#x4F53;&#x7BC0;&#x982D;&#x306E;&#x8EE2;&#x5199;&#x3067;&#x306F;&#x3001;&#x3053;&#x306E;&#x5074;&#x9762;&#x304B;&#x3089;&#x5185;&#x5074;&#x30B7;&#x30D5;&#x30C8;&#x3092;&#x5236;&#x5FA1;&#x56E0;&#x5B50;&#xFF08;s&#xFF09;&#x3092;&#x8ABF;&#x3079;&#x305F;&#x3002;&#x5C3E;&#x5074;&#x677F;/&#x4E2D;&#x9593;&#x4E2D;&#x80DA;&#x8449;&#x3067;BMP&#x6D3B;&#x6027;&#x306E;&#x963B;&#x5BB3;&#x306F;&#x3001;&#x6A2A;&#x4F53;&#x7BC0;&#x306E;&#x982D;&#x306E;&#x8EE2;&#x5199;&#x3092;&#x6291;&#x5236;&#x3057;&#x305F;&#x3002;&#x3055;&#x3089;&#x306B;&#x543B;&#x65B9;&#xFF08;&#x307E;&#x305F;&#x306F;&#x305D;&#x308C;&#x4EE5;&#x964D;&#x958B;&#x767A;&#x4E2D;&#xFF09;&#x3001;&#x7BA1;&#x7531;&#x6765;&#x306E;BMP&#x306E;&#x3067;&#x306F;&#x306A;&#x304F;&#x3001;Wnt&#x30B7;&#x30B0;&#x30CA;&#x30EB;&#x6D3B;&#x6027;&#x306E;&#x963B;&#x5BB3;&#x306F;&#x3001;dermomyotome&#x306E;&#x80CC;&#x5185;&#x5074;&#x5507;&#x306B;&#x6700;&#x521D;&#x306E;&#x982D;&#x306E;&#x767A;&#x73FE;&#x3092;&#x6291;&#x5236;&#x3057;&#x305F;&#x3002;&#x3055;&#x3089;&#x306B;&#x3001;BMP4&#x306F;&#x80CC;&#x5185;&#x5074;&#x4F53;&#x7BC0;&#x3078;&#x306E;&#x76F4;&#x63A5;&#x4F5C;&#x7528;&#x3092;&#x793A;&#x5506;&#x3057;&#x3066;&#x3001;&#x5916;&#x80DA;&#x8449;&#x3001;&#x304A;&#x3088;&#x3073;/&#x307E;&#x305F;&#x306F;&#x795E;&#x7D4C;&#x7BA1;&#x306E;&#x975E;&#x5B58;&#x5728;&#x4E0B;&#x3067;&#x3055;&#x3048;&#x982D;&#x306E;&#x6700;&#x521D;&#x306E;&#x767A;&#x73FE;&#x3092;&#x5F15;&#x304D;&#x8D77;&#x3053;&#x3059;&#x306E;&#x306B;&#x5341;&#x5206;&#x3067;&#x3042;&#x3063;&#x305F;&#x3002;&#x3057;&#x305F;&#x304C;&#x3063;&#x3066;&#x3001;&#x4F53;&#x7BC0;&#x306E;&#x30CE;&#x30AE;&#x30F3;&#x8EE2;&#x5199;&#x306E;&#x30D1;&#x30BF;&#x30FC;&#x30F3;&#x306F;&#x3001;&#x76F4;&#x63A5;&#x795E;&#x7D4C;&#x7BA1;&#x3067;&#x5F8C;&#x304B;&#x3089;&#x4E2D;&#x80DA;&#x8449;&#x304B;&#x3089;&#x306E;&#x6700;&#x521D;&#x306E;&#x767A;&#x6563;&#x3068;BMP4&#x306E;&#x6D3B;&#x52D5;&#x306B;&#x3088;&#x3063;&#x3066;&#x898F;&#x5236;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;&#x3002; BMP4&#x304A;&#x3088;&#x3073;&#x30BF;&#x30A4;&#x30D7;IA BMP&#x53D7;&#x5BB9;&#x4F53;&#x306E;&#x767A;&#x73FE;&#x30D1;&#x30BF;&#x30FC;&#x30F3;&#x306F;&#x3001;&#x3053;&#x306E;&#x5074;&#x9762;&#x304B;&#x3089;&#x5185;&#x5074;&#x30B7;&#x30D5;&#x30C8;&#x6642;&#x7A7A;&#x4E92;&#x63DB;&#x6027;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x3053;&#x308C;&#x3089;&#x306E;&#x7D50;&#x679C;&#x306F;&#x3001;BMP&#x306F;&#x7A4D;&#x6975;&#x7684;&#x306B;&#x9806;&#x756A;&#x306B;&#x3001;&#x3055;&#x3089;&#x306B;&#x30EA;&#x30AC;&#x30F3;&#x30C9;&#x6D3B;&#x6027;&#x3092;&#x6291;&#x5236;&#x3059;&#x308B;&#x30CE;&#x30AE;&#x30F3;&#x306E;&#x8EE2;&#x5199;&#x3092;&#x8ABF;&#x7BC0;&#x3059;&#x308B;&#x3053;&#x3068;&#x306B;&#x3088;&#x3063;&#x3066;&#x8ABF;&#x7BC0;&#x30EB;&#x30FC;&#x30D7;&#x306E;&#x795E;&#x7D4C;&#x7BA1;&#x3001;&#x4E2D;&#x80DA;&#x8449;&#x8907;&#x5408;&#x4F53;&#x306E;&#x5B58;&#x5728;&#x3092;&#x5F37;&#x8ABF;&#x8868;&#x793A;&#x3057;&#x307E;&#x3059;&#x3002;

&#x30ED;&#x30FC;&#x30AB;&#x30E9;&#x30A4;&#x30BA;&#x3055;&#x308C;&#x305F;BMP4-&#x30CE;&#x30AE;&#x30F3;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x306F;&#x3001;&#x4F53;&#x7BC0;&#x306E;&#x30CE;&#x30AE;&#x30F3;&#x767A;&#x73FE;&#x306E;&#x52D5;&#x7684;&#x30D1;&#x30BF;&#x30FC;&#x30CB;&#x30F3;&#x30B0;&#x3092;&#x751F;&#x6210;&#x3057;&#x307E;&#x3059;&#x3002;

Bmp4&#xC640; &#xC5B5;&#xC81C;&#xC81C;, &#xBA38;&#xB9AC;, &#xAC04;&#xC758; &#xC0C1;&#xD638; &#xC791;&#xC6A9; somites&#xACFC; &#xC2E0;&#xACBD;&#xB3C4;&#xAC00; &#xBA38;&#xB9AC;&#xC758; &#xD328;&#xD134;&#xD654; &#xD560; &#xADDC;&#xC81C;. Mesoderm &#xAC1C;&#xBC1C; &#xBA38;&#xB9AC; mRNA &#xC911;&#xAC04; mesoderm&#xC5D0;&#xC11C; &#xD45C;&#xD604; &#xB41C;&#xB2E4;. &#xC138;&#xBD84;&#xD654;, &#xC2DC; &#xC0C1;&#xD53C; somites &#xADF8;&#xB4E4;&#xC740; &#xC131;&#xC219; medialized &#xC810;&#xCC28;&#xC801;&#xC73C;&#xB85C; &#xC9C0; &#xACE0;&#xC758; &#xCE21;&#xBA74; &#xBD80;&#xBD84;&#xC5D0; &#xAC10;&#xC9C0; &#xD569;&#xB2C8;&#xB2E4;. &#xCC9C;&#xC5F0;&#xB41C; &#xC138;&#xADF8;&#xBA3C;&#xD2B8;&#xC5D0;&#xC11C; &#xBA38;&#xB9AC; &#xB418; &#xACE0; transiently&#xB294; dermomyotome&#xC758; dorsomedial &#xC785;&#xC220;&#xC5D0; &#xAD6D;&#xD55C; &#xB429;&#xB2C8;&#xB2E4;. &#xC5EC;&#xAE30;, &#xC6B0;&#xB9AC; factor(s) somitic &#xBA38;&#xB9AC;&#xC758; &#xC804;&#xC0AC;&#xC5D0;&#xC11C; &#xCE21;&#xBA74; &#xC911;&#xAC04; &#xBCC0;&#xD654;&#xB97C; &#xC81C;&#xC5B4; &#xD558;&#xB294; &#xC870;&#xC0AC;. &#xAF2C;&#xB9AC; &#xCE21;&#xBA74; &#xD50C;&#xB808;&#xC774;&#xD2B8;/&#xC911;&#xAC04; mesoderm&#xC5D0;&#xC11C; BMP &#xD65C;&#xB3D9;&#xC758; &#xC800;&#xD574; &#xBC29;&#xC9C0; &#xCE21;&#xBA74; somite&#xC5D0; &#xC18C;&#xB7C9; &#xC804;&#xC0AC;. Rostrally &#xCD94;&#xAC00; (&#xB610;&#xB294; &#xB098;&#xC911;&#xC5D0; &#xAC1C;&#xBC1C;&#xC5D0;), &#xD29C;&#xBE0C; &#xD30C;&#xC0DD; &#xB41C; BMP&#xC758; &#xC544;&#xB2C8;&#xC9C0;&#xB9CC; Wnt &#xD65C;&#xB3D9;&#xC758; &#xC800;&#xD574; &#xBC29;&#xC9C0;&#xB294; dermomyotome&#xC758; dorsomedial &#xC785;&#xC220;&#xC5D0; &#xCD08;&#xAE30; &#xC18C;&#xB7C9; &#xC2DD;. &#xB610;&#xD55C;, BMP4 dorsomedial somite&#xC5D0; &#xC9C1;&#xC811; &#xD589;&#xB3D9; &#xC81C;&#xC548; ectoderm &#xC2E0;&#xACBD; &#xD29C;&#xBE0C;&#xC758; &#xBD80;&#xC7AC;&#xC5D0;&#xB3C4; &#xBA38;&#xB9AC;&#xC758; &#xCD08;&#xAE30; &#xC2DD;&#xC744; &#xC2E4;&#xD589; &#xD558;&#xB294; &#xB370; &#xCDA9;&#xBD84; &#xD588;&#xB2E4;. &#xB530;&#xB77C;&#xC11C;, somites&#xC5D0; &#xC18C;&#xB7C9; &#xC804;&#xC0AC;&#xC758; &#xD328;&#xD134;&#xC740; &#xC9C1;&#xC811; BMP4 &#xD65C;&#xB3D9;&#xC740; mesoderm&#xC5D0;&#xC11C; &#xBA3C;&#xC800; &#xC9D1;&#xC911;&#xC801;&#xC73C;&#xB85C; &#xADDC;&#xC81C; &#xD558; &#xACE0; &#xC2E0;&#xACBD; &#xD29C;&#xBE0C;&#xC5D0;&#xC11C; &#xC774;&#xC0C1;. &#xC2DD; &#xD328;&#xD134; &#xC720;&#xD615; IA BMP &#xC218;&#xC6A9; &#xCCB4;&#xC640; bmp4&#xC758; spatiotemporally&#xC774; &#xCE21;&#xBA74; &#xC911;&#xAC04; &#xC2DC;&#xD504;&#xD2B8;&#xC640; &#xD638;&#xD658; &#xB429;&#xB2C8;&#xB2E4;. &#xC774;&#xB7EC;&#xD55C; &#xACB0;&#xACFC;&#xB294; BMP &#xAE0D;&#xC815;&#xC801;&#xC73C;&#xB85C; &#xCC28;&#xB840;&#xB85C; &#xCD94;&#xAC00; &#xB9AC;&#xAC04;&#xB4DC; &#xD65C;&#xB3D9;&#xC744; &#xB204;&#xB974;&#xB294; &#xBA38;&#xB9AC;&#xC758; &#xC804;&#xC0AC; &#xC870;&#xC808; &#xADDC;&#xC81C; &#xB8E8;&#xD504;&#xC758; &#xC2E0;&#xACBD; &#xD29C;&#xBE0C; mesoderm &#xBCF5;&#xC7A1; &#xD55C; &#xC874;&#xC7AC;&#xB97C; &#xAC15;&#xC870; &#xD45C;&#xC2DC; &#xD569;&#xB2C8;&#xB2E4;.

&#xC9C0;&#xC5ED;&#xD654; &#xB41C; BMP4 &#xBA38;&#xB9AC; &#xC0C1;&#xD638; &#xC791;&#xC6A9; somites&#xC5D0; &#xC18C;&#xB7C9; &#xC2DD;&#xC758; &#xB3D9;&#xC801; &#xD328;&#xD134;&#xD654;&#xB97C; &#xC0DD;&#xC131;&#xD569;&#xB2C8;&#xB2E4;.

Las interacciones entre BMP4 y su inhibidor de la bocha, regular el patr&#xF3;n de los somitas y de la cresta neural. Durante el desarrollo mesodermo, ARNm Noggin se expresa en el mesodermo intermedio. Despu&#xE9;s de la segmentaci&#xF3;n, se detecta en la parte lateral de somitas epiteliales se conviertan progresivamente medializado a medida que maduran. En los segmentos disociados, noggin se convierte transitoriamente confinado al borde dorsomedial del dermomiotoma. En este caso, se determin&#xF3; el factor (s) que controlan el desplazamiento lateral a medial en la transcripci&#xF3;n de noggin som&#xED;ticos. La inhibici&#xF3;n de la actividad de BMP en el caudal de la placa lateral / intermedio mesodermo prevenir la transcripci&#xF3;n bocha en el somite lateral. Adem&#xE1;s rostral (o m&#xE1;s adelante en el desarrollo), la inhibici&#xF3;n de la sonda derivada de BMP, pero no de la v&#xED;a de Wnt, impidi&#xF3; que la expresi&#xF3;n inicial de bocha en el labio dorsomedial del dermomiotoma. Adem&#xE1;s, BMP4 era suficiente para activar la expresi&#xF3;n inicial de noggin incluso en ausencia de ectodermo y / o del tubo neural, lo que sugiere una acci&#xF3;n directa sobre el somito dorsomedial. Por lo tanto, los patrones de transcripci&#xF3;n bocha en somitas son regulados directamente por las actividades que emanan de BMP4 primero del mesodermo y m&#xE1;s tarde de que el tubo neural. Los patrones de expresi&#xF3;n de BMP4 y de tipo IA receptores BMP son espaciotemporalmente compatibles con este cambio de lateral a medial. Estos resultados ponen de manifiesto la existencia en el tubo neural, mesodermo complejo de un bucle de regulaci&#xF3;n por el cual BMP regula positivamente la transcripci&#xF3;n de la bocha, que a su vez reprime la actividad ligando m&#xE1;s.

Localizadas noggin BMP4 interacciones generan el patr&#xF3;n din&#xE1;mico de Expresi&#xF3;n Noggin en somitas

Premigratory &#x795E;&#x7ECF;&#x5D74;&#x7EC6;&#x80DE;&#x5206;&#x5C42;&#x53D6;&#x51B3;&#x4E8E; BMP/&#x8111;&#x888B;&#x4E4B;&#x95F4;&#x7684;&#x5E73;&#x8861;&#x548C; G1/S &#x6210;&#x529F;&#x8F6C;&#x578B;&#x3002;&#x5728;&#x8FD9;&#x91CC;&#xFF0C;&#x6211;&#x4EEC;&#x62A5;&#x544A; BMP &#x89C4;&#x8303; G1/S &#x8FC7;&#x6E21;&#x548C;&#x901A;&#x8FC7;&#x89C4;&#x8303; Wnt &#x4FE1;&#x53F7;&#x7531;&#x6B64;&#x9876;&#x5206;&#x5C42;&#x3002;&#x8111;&#x888B;&#x8FC7;&#x5EA6;&#x8868;&#x8FBE;&#x6291;&#x5236; G1/S &#x8FC7;&#x6E21;&#x548C;&#x963B;&#x6B62; G1/S &#x5E9F;&#x9664; BMP &#x8BF1;&#x5BFC;&#x5206;&#x5C42; &#xFF1B;&#x6B64;&#x5916;&#xFF0C;Wnt1 &#x8F6C;&#x5F55;&#x88AB;&#x523A;&#x6FC0; BMP &#x548C;&#x53D1;&#x5C55;&#x4E2D;&#x56FD;&#x5BB6;&#x7684; somites&#xFF0C;&#x540C;&#x65F6;&#x6291;&#x5236;&#x8111;&#x888B;&#x751F;&#x4EA7;&#x3002;&#x8FDE;&#x73AF;&#x548C;&#x5DE6;&#x952E;/TCF &#x5E72;&#x6270;&#x6291;&#x5236; G1/S &#x8FC7;&#x6E21;&#x3001; &#x795E;&#x7ECF;&#x5D74;&#x5206;&#x5C42;&#x548C;&#x8F6C;&#x5F55;&#x7684;&#x5404;&#x79CD;&#x4F9D;&#x8D56;&#x4E8E;&#x9AA8;&#x5F62;&#x6001;&#x53D1;&#x751F;&#x86CB;&#x767D;&#x7684;&#x57FA;&#x56E0;&#xFF0C;&#x5305;&#x62EC; Cad6B&#x3001; Pax3 &#x548C; Msx1&#xFF0C;&#x4F46;&#x4E0D;&#x662F;&#x86DE;&#x8753;&#x3001; Sox9 &#x6216; FoxD3&#x3002;&#x56E0;&#x6B64;&#xFF0C;&#x6211;&#x4EEC;&#x5EFA;&#x8BAE;&#x53D1;&#x5C55; somites &#x6291;&#x5236;&#x80CC;&#x7BA1;&#xFF0C;&#x8111;&#x888B;&#x8F6C;&#x5F55;&#x6FC0;&#x6D3B; BMP &#x548C; Wnt1 &#x7531;&#x6B64;&#x4EA7;&#x751F;&#x7684;&#x7ED3;&#x679C;&#x3002;&#x89C4;&#x8303; Wnt &#x4FE1;&#x53F7;&#x7684;&#x540C;&#x65F6;&#x53C8;&#x523A;&#x6FC0;&#x4E86; G1/S &#x8FC7;&#x6E21;&#x548C;&#x72EC;&#x7ACB;&#x65E9;&#x671F;&#x795E;&#x7ECF;&#x5D74;&#x89C4;&#x8303;&#x5176;&#x62DF;&#x8BAE;&#x4F5C;&#x7528;&#x4E8E;&#x795E;&#x7ECF;&#x5D74;&#x7EC6;&#x80DE;&#x8FD0;&#x52A8;&#x7684;&#x4E00;&#x4EE3;&#x3002;

&#x89C4;&#x8303; Wnt &#x6D3B;&#x52A8;&#x89C4;&#x5B9A;&#x4E86;&#x4E3B;&#x5E72;&#x795E;&#x7ECF;&#x5D74;&#x5206;&#x5C42;&#x94FE;&#x63A5; BMP/&#x8111;&#x888B;&#x4E0E; G1/S &#x8FC7;&#x6E21;&#x4FE1;&#x53F7;&#x3002;

Delamination of premigratory neural crest cells depends on a balance between BMP/noggin and on successful G1/S transition. Here, we report that BMP regulates G1/S transition and consequent crest delamination through canonical Wnt signaling. Noggin overexpression inhibits G1/S transition and blocking G1/S abrogates BMP-induced delamination; moreover, transcription of Wnt1 is stimulated by BMP and by the developing somites, which concomitantly inhibit noggin production. Interfering with beta-catenin and LEF/TCF inhibits G1/S transition, neural crest delamination and transcription of various BMP-dependent genes, which include Cad6B, Pax3 and Msx1, but not that of Slug, Sox9 or FoxD3. Hence, we propose that developing somites inhibit noggin transcription in the dorsal tube, resulting in activation of BMP and consequent Wnt1 production. Canonical Wnt signaling in turn stimulates G1/S transition and generation of neural crest cell motility independently of its proposed role in earlier neural crest specification.

Canonical Wnt activity regulates trunk neural crest delamination linking BMP/noggin signaling with G1/S transition.

La d&#xE9;lamination des cellules des cr&#xEA;tes neurales pr&#xE9;migratoire d&#xE9;pend d&#x26;#39;un &#xE9;quilibre entre les BMP / noggine et le G1 succ&#xE8;s / S de transition. Ici, nous d&#xE9;clarons que BMP r&#xE9;glemente la transition G1 / S et la cr&#xEA;te cons&#xE9;quente d&#xE9;lamination par voie de signalisation Wnt canonique. Surexpression noggine inhibe la transition G1 / S et de blocage G1 / S abroge BMP-induite d&#xE9;lamination; outre, la transcription de la Wnt1 est stimul&#xE9;e par BMP et par des somites d&#xE9;veloppement, qui inhibent la production de mani&#xE8;re concomitante noggine. Interf&#xE9;rer avec la b&#xEA;ta-cat&#xE9;nine et LEF / TCF inhibe la transition G1 / S, de la cr&#xEA;te neurale d&#xE9;lamination et la transcription de divers g&#xE8;nes BMP-d&#xE9;pendants, qui comprennent Cad6B, Pax3 et Msx1, mais pas celle de Slug, Sox9 ou FoxD3. Par cons&#xE9;quent, nous proposons que somites d&#xE9;veloppement inhiber la transcription noggine dans le tube dorsal, r&#xE9;sultant en une activation de BMP et de la production Wnt1 cons&#xE9;quente. Canonique de signalisation Wnt &#xE0; son tour stimule la transition G1 / S et la g&#xE9;n&#xE9;ration de cellules de la cr&#xEA;te neurale motilit&#xE9; ind&#xE9;pendamment de son r&#xF4;le dans la sp&#xE9;cification propos&#xE9;e cr&#xEA;te neurale t&#xF4;t.

Canonique Wnt activit&#xE9; R&#xE9;gule Crest Trunk Neural d&#xE9;laminage Lier BMP / caboche de signalisation avec transition G1 / S

Wnt-Aktivit&#xE4;t reguliert Stamm Neuralleiste Delamination Verkn&#xFC;pfung BMP / noggin Signalisierung mit G1 / S &#xDC;bergang.

Delaminazione delle cellule della cresta neurale premigratory dipende dall&#39;equilibrio tra BMP/noggin e sul successo della transizione G1/S. Qui, segnaliamo che BMP regola la transizione G1/S e delaminazione conseguente cresta attraverso segnalazione Wnt canonico. Sovraespressione di zucca inibisce la transizione G1/S e blocco G1/S abroga indotta da BMP delaminazione; Inoltre, trascrizione di Wnt1 &egrave; stimolata da BMP e i somiti in via di sviluppo, che simultaneamente inibiscono la produzione di zucca. Interferire con la beta-catenina e TCF/LEF inibisce G1/S transizione, dalla cresta neurale delaminazione e trascrizione di vari geni BMP-dipendente, che includono Cad6B, Pax3 e Msx1, ma non quello di Slug, Sox9 o FoxD3. Quindi, noi proponiamo che sviluppo somiti inibiscono trascrizione noggin nel tubo dorsale, con conseguente attivazione del BMP e conseguente produzione di Wnt1. Segnalazione Wnt canonico a sua volta stimola la transizione G1/S e la generazione della cresta neurale motilit&agrave; cellulare indipendentemente dal suo ruolo proposto nella precedente cresta neurale specifica.

Attivit&agrave; canonica di Wnt regola delaminazione cresta neurale tronco che collega BMP/noggin segnalazione con transizione G1/S.

premigratory&#x795E;&#x7D4C;&#x5824;&#x7D30;&#x80DE;&#x306E;&#x5265;&#x96E2;BMP /&#x982D;&#x306E;&#x9593;&#x306E;&#x30D0;&#x30E9;&#x30F3;&#x30B9;&#x306B;&#x6210;&#x529F;&#x3057;&#x305F;G1 / S&#x79FB;&#x884C;&#x306B;&#x4F9D;&#x5B58;&#x3057;&#x307E;&#x3059;&#x3002;&#x3053;&#x3053;&#x3067;&#x306F;&#x3001;BMP&#x306F;&#x3001;G1 / S&#x79FB;&#x884C;&#x3057;&#x3001;&#x305D;&#x306E;&#x7D50;&#x679C;&#x9802;&#x4E0A;&#x306F;Wnt&#x30B7;&#x30B0;&#x30CA;&#x30EB;&#x3092;&#x4ECB;&#x3057;&#x3066;&#x5265;&#x96E2;&#x8ABF;&#x7BC0;&#x3057;&#x3066;&#x3044;&#x308B;&#x3053;&#x3068;&#x3092;&#x5831;&#x544A;&#x3057;&#x307E;&#x3059;&#x3002;&#x30CE;&#x30AE;&#x30F3;&#x306E;&#x904E;&#x5270;&#x767A;&#x73FE;&#x306F;G1 / S&#x79FB;&#x884C;&#x3068;G1 / S abrogates BMP&#x306B;&#x3088;&#x3063;&#x3066;&#x8A98;&#x5C0E;&#x3055;&#x308C;&#x308B;&#x5265;&#x96E2;&#x3092;&#x30D6;&#x30ED;&#x30C3;&#x30AF;&#x3092;&#x963B;&#x5BB3;&#x3057;&#x3001;&#x307E;&#x305F;&#x3001;Wnt1&#x306E;&#x8EE2;&#x5199;&#x306F;BMP&#x306B;&#x3088;&#x3063;&#x3066;&#x3068;&#x4F75;&#x7528;&#x982D;&#x306E;&#x7523;&#x751F;&#x3092;&#x963B;&#x5BB3;&#x3059;&#x308B;&#x958B;&#x767A;&#x4F53;&#x7BC0;&#x306B;&#x3088;&#x3063;&#x3066;&#x523A;&#x6FC0;&#x3055;&#x308C;&#x308B;&#x3002; G1 / S&#x79FB;&#x884C;&#x3092;&#x963B;&#x5BB3;&#x3059;&#x308B;&#x3B2;-&#x30AB;&#x30C6;&#x30CB;&#x30F3;&#x3068;LEF / TCF&#x306B;&#x5E72;&#x6E09;&#x3059;&#x308B;&#x3001;&#x795E;&#x7D4C;&#x5824;&#x306B;&#x306F;&#x3001;&#x5C64;&#x9593;&#x5265;&#x96E2;&#x3068;Cad6B&#x3001;PAX3&#x3068;MSX1&#x3067;&#x306F;&#x306A;&#x304F;&#x3001;&#x30B9;&#x30E9;&#x30C3;&#x30B0;&#x3001;Sox9&#x3092;&#x307E;&#x305F;&#x306F;FoxD3&#x306E;&#x305D;&#x308C;&#x3092;&#x542B;&#x3080;&#x69D8;&#x3005;&#x306A;BMP-&#x4F9D;&#x5B58;&#x907A;&#x4F1D;&#x5B50;&#x306E;&#x8EE2;&#x5199;&#x304C;&#x53EF;&#x80FD;&#x306B;&#x306A;&#x308B;&#x3002;&#x3057;&#x305F;&#x304C;&#x3063;&#x3066;&#x3001;&#x6211;&#x3005;&#x306F;&#x3001;&#x767A;&#x5C55;&#x9014;&#x4E0A;&#x4F53;&#x7BC0;&#x306F;&#x3001;BMP&#x304A;&#x3088;&#x3073;&#x305D;&#x306E;&#x7D50;&#x679C;Wnt1&#x751F;&#x7523;&#x306E;&#x6D3B;&#x6027;&#x5316;&#x3001;&#x305D;&#x306E;&#x7D50;&#x679C;&#x3001;&#x80CC;&#x5074;&#x306E;&#x30C1;&#x30E5;&#x30FC;&#x30D6;&#x306B;&#x982D;&#x306E;&#x8EE2;&#x5199;&#x3092;&#x6291;&#x5236;&#x3059;&#x308B;&#x3053;&#x3068;&#x3092;&#x63D0;&#x6848;&#x3059;&#x308B;&#x3002;&#x9806;&#x756A;&#x306B;Wnt&#x30B7;&#x30B0;&#x30CA;&#x30EB;&#x306F;&#x3001;G1 / S&#x79FB;&#x884C;&#x3001;&#x72EC;&#x7ACB;&#x4EE5;&#x524D;&#x306E;&#x795E;&#x7D4C;&#x5824;&#x306E;&#x4ED5;&#x69D8;&#x3067;&#x306F;&#x3001;&#x63D0;&#x6848;&#x3055;&#x308C;&#x305F;&#x5F79;&#x5272;&#x306E;&#x795E;&#x7D4C;&#x5824;&#x7D30;&#x80DE;&#x306E;&#x904B;&#x52D5;&#x6027;&#x306E;&#x751F;&#x6210;&#x3092;&#x523A;&#x6FC0;&#x3059;&#x308B;&#x3002;

&#x30AB;&#x30CE;&#x30CB;&#x30AB;&#x30EB;Wnt&#x30B7;&#x30B0;&#x30CA;&#x30EB;&#x6D3B;&#x6027;&#x306F;BMP /&#x982D;&#x306F;&#x3001;G1 / S&#x79FB;&#x884C;&#x3067;&#x306E;&#x30B7;&#x30B0;&#x30CA;&#x30EA;&#x30F3;&#x30B0;&#x30EA;&#x30F3;&#x30AF;&#x5265;&#x96E2;&#x4F53;&#x5E79;&#x795E;&#x7D4C;&#x51A0;&#x3092;&#x8ABF;&#x7BC0;&#x3059;&#x308B;

Premigratory &#xC2E0;&#xACBD; &#xD06C;&#xB808;&#xC2A4;&#xD2B8; &#xC138;&#xD3EC;&#xC758; &#xBC15; &#xB9AC; &#xBC0F; &#xC131;&#xACF5;&#xC801;&#xC778; G1/S &#xC804;&#xD658; BMP/&#xBA38;&#xB9AC; &#xC0AC;&#xC774;&#xC758; &#xADE0;&#xD615;&#xC5D0; &#xB530;&#xB77C; &#xB2E4;&#xB985;&#xB2C8;&#xB2E4;. &#xC5EC;&#xAE30;, &#xC6B0;&#xB9AC; &#xBCF4;&#xACE0; BMP G1/S &#xC804;&#xD658; &#xBC0F; &#xD544;&#xC5F0;&#xC801;&#xC778; &#xD06C;&#xB808;&#xC2A4;&#xD2B8; &#xBC15; &#xB9AC; &#xC815;&#xC2DD; Wnt &#xC2E0;&#xD638;&#xB97C; &#xD1B5;&#xD574; &#xC870;&#xC808; &#xD569;&#xB2C8;&#xB2E4;. &#xBA38;&#xB9AC; overexpression G1/S &#xC804;&#xD658; &#xC5B5;&#xC81C; &#xD558; &#xACE0; G1/S &#xCC28;&#xB2E8; &#xB418;&#xC5B4;&#xC788;&#xB294; BMP &#xC720;&#xB3C4; &#xBC15; &#xB9AC;; &#xB610;&#xD55C;, wnt1&#xC758; &#xC804;&#xC0AC;&#xB294; BMP &#xBC0F; &#xAC1C;&#xBC1C; somites concomitantly &#xC18C;&#xB7C9; &#xC0DD;&#xC0B0;&#xC744; &#xC5B5;&#xC81C; &#xD558;&#xB294; &#xC790;&#xADF9; &#xC774;&#xB2E4;. &#xBCA0;&#xD0C0;-catenin &#xBC0F; LEF/TCF&#xB97C; &#xBC29;&#xD574; &#xD558;&#xB294; &#xAC83;&#xC740; G1/S &#xC804;&#xD658;, &#xC2E0;&#xACBD;&#xB3C4;&#xAC00; &#xBA38;&#xB9AC; &#xBC15; &#xB9AC;&#xC640; Cad6B, Pax3 &#xBC0F; msx1&#xC744; &#xD3EC;&#xD568;, &#xB2E4;&#xC591; &#xD55C; BMP &#xC885;&#xC18D; &#xC720;&#xC804;&#xC790;&#xC758; &#xC804;&#xC0AC; &#xD558;&#xC9C0;&#xB9CC; &#xADF8; &#xB290; &#xB9BF; &#xB290; &#xB9BF;, Sox9 &#xB610;&#xB294; Foxd3&#xC744; &#xC5B5;&#xC81C; &#xD55C;&#xB2E4;. &#xB530;&#xB77C;&#xC11C;, &#xC6B0;&#xB9AC;&#xB294; &#xC81C;&#xC548; &#xAC1C;&#xBC1C; somites &#xC9C0; &#xAD00;&#xC5D0; &#xC18C;&#xB7C9; &#xC804;&#xC0AC; &#xC5B5;&#xC81C; BMP &#xBC0F; &#xACB0;&#xACFC; Wnt1 &#xC0DD;&#xC0B0;&#xC758; &#xD65C;&#xC131;&#xD654;&#xC758; &#xACB0;&#xACFC;&#xB85C;. G1/S &#xC804;&#xD658; &#xBC0F; &#xC774;&#xC804; &#xC2E0;&#xACBD; &#xD06C;&#xB808;&#xC2A4;&#xD2B8; &#xC0AC;&#xC591;&#xC5D0;&#xC11C;&#xC758; &#xC81C;&#xC548; &#xB41C; &#xC5ED;&#xD560; &#xBCC4;&#xB3C4;&#xB85C; &#xC2E0;&#xACBD; &#xD06C;&#xB808;&#xC2A4;&#xD2B8; &#xC138;&#xD3EC; &#xC6B4;&#xB3D9; &#xC131; &#xC790;&#xADF9;&#xC5D0; &#xC815;&#xC2DD; Wnt &#xC2E0;&#xD638;.

&#xC815;&#xC2DD; Wnt &#xD65C;&#xB3D9; &#xADDC;&#xC81C; &#xD2B8;&#xB801;&#xD06C; &#xC2E0;&#xACBD;&#xB3C4;&#xAC00; &#xBA38;&#xB9AC; &#xBC15; &#xB9AC; BMP/&#xBA38;&#xB9AC; G1/S &#xC804;&#xD658; &#xC2E0;&#xD638;&#xB97C; &#xC5F0;&#xACB0; &#xD569;&#xB2C8;&#xB2E4;.

Delaminaci&#xF3;n de las c&#xE9;lulas de la cresta neural premigratorias depende de un equilibrio entre BMP / bocha y el &#xE9;xito G1 / S transici&#xF3;n. En este caso, nos informan de que BMP regula la transici&#xF3;n G1 / S y la cresta consecuente delaminaci&#xF3;n a trav&#xE9;s de se&#xF1;alizaci&#xF3;n Wnt can&#xF3;nica. Sobreexpresi&#xF3;n Noggin inhibe la transici&#xF3;n G1 / S y la delaminaci&#xF3;n bloqueo G1 / S abroga BMP-inducida y, adem&#xE1;s, la transcripci&#xF3;n de Wnt1 es estimulada por la BMP y por las somitas en desarrollo, que simult&#xE1;neamente inhiben la producci&#xF3;n de bocha. Interferir con la beta-catenina y LEF / TCF inhibe la transici&#xF3;n G1 / S, la delaminaci&#xF3;n de la cresta neural y la transcripci&#xF3;n de varios genes BMP-dependientes, que incluyen Cad6B, Pax3 y MSX1, pero no la de Slug, Sox9 o FoxD3. Por lo tanto, proponemos que somitas desarrollo inhibir la transcripci&#xF3;n bocha en el tubo dorsal, lo que resulta en la activaci&#xF3;n de BMP y la producci&#xF3;n Wnt1 consecuente. Se&#xF1;alizaci&#xF3;n Wnt can&#xF3;nica, a su vez estimula la transici&#xF3;n G1 / S y la generaci&#xF3;n de la motilidad c&#xE9;lulas de la cresta neural, independientemente de su papel en la especificaci&#xF3;n propuesta cresta neural anterior.

Actividad Wnt can&#xF3;nica Regula la cresta neural del tronco delaminaci&#xF3;n Vinculaci&#xF3;n BMP / bocha de se&#xF1;alizaci&#xF3;n con la transici&#xF3;n G1 / S

Eph receptors and ephrins can sharpen domains within developing tissues by mediating repulsion at interfaces. An Eph receptor has now been shown also to regulate cell adhesion within tissue subdivisions.

Eph receptors: two ways to sharpen boundaries.

&Eacute;phrines et r&eacute;cepteurs Eph peut aiguiser des domaines au sein de d&eacute;veloppement des tissus par la m&eacute;diation de r&eacute;pulsion aux interfaces. Un r&eacute;cepteurs Eph a maintenant &eacute;t&eacute; &eacute;tabli &eacute;galement r&eacute;glementer l&#39;adh&eacute;sion cellulaire au sein des subdivisions de tissu.

R&eacute;cepteurs EPH : deux fa&ccedil;ons pour aff&ucirc;ter les limites.

Ephrins e recettori Eph pu&ograve; affinare domini all&#39;interno di sviluppare tessuti di repulsione a interfacce di mediazione. Un recettore EF ora &egrave; stato dimostrato anche per regolare l&#39;adesione delle cellule all&#39;interno delle suddivisioni dei tessuti.

Recettori EPH: due modi per affinare i confini.

Il faut un r&eacute;seau d&#39;interactions mol&eacute;culaires dans le rhombenc&eacute;phale vert&eacute;br&eacute; en d&eacute;veloppement pour la formation et la structuration ant&eacute;ro-post&eacute;rieur de le rhombomeres. Signalisation de FGF est requise dans ce r&eacute;seau &agrave; r&eacute;guler positivement que l&#39;expression des g&egrave;nes de segmentation Krox20 et Kreisler, mais peu est connue de comment l&#39;expression des g&egrave;nes FGF est r&eacute;gul&eacute;e dans le cerveau post&eacute;rieur. Nous montrons que l&#39;expression dynamique de FGF3 dans les segments de cerveau post&eacute;rieur de Poussin et de limites est semblable &agrave; celle de l&#39;antagoniste BMP, follistatine. Conform&eacute;ment &agrave; une r&eacute;glementation relation entre BMP signaling et expression de le FGF3, nous trouvons qu&#39;une augmentation dans l&#39;activit&eacute; BMP due au blocage de la traduction de follistatine par morpholino antisens ou surexpression de BMP des r&eacute;sultats en forte inhibition de l&#39;expression FGF3. &Agrave; l&#39;inverse, ajout de follistatine entra&icirc;ne une augmentation du niveau d&#39;expression de FGF3. De plus, l&#39;inhibition segmentaire de l&#39;activit&eacute; BMP par follistatin est n&eacute;cessaire pour l&#39;expression de Krox20, Hoxb1 et EphA4 dans le cerveau post&eacute;rieur. En outre, nous montrons que le maintien de l&#39;expression g&eacute;nique FGF3 exige activit&eacute; FGF, &eacute;vocateur d&#39;une boucle de l&#39;autor&eacute;gulation. Ces r&eacute;sultats r&eacute;v&egrave;lent une relation antagoniste entre activit&eacute; BMP et expression de FGF3 qui est n&eacute;cessaire pour l&#39;expression du g&egrave;ne segmentaire correcte dans le cerveau post&eacute;rieur de poussin, dans laquelle follistatine permet FGF3 expression en inhibant l&#39;activit&eacute; BMP.

Inhibition des PGB par follistatin est requise pour expression FGF3 et structuration segmentaire du cerveau post&eacute;rieur.

A network of molecular interactions is required in the developing vertebrate hindbrain for the formation and anterior-posterior patterning of the rhombomeres. FGF signaling is required in this network to upregulate the expression of the Krox20 and Kreisler segmentation genes, but little is known of how FGF gene expression is regulated in the hindbrain. We show that the dynamic expression of FGF3 in chick hindbrain segments and boundaries is similar to that of the BMP antagonist, follistatin. Consistent with a regulatory relationship between BMP signaling and FGF3 expression, we find that an increase in BMP activity due to blocking of follistatin translation by morpholino antisense oligonucleotides or overexpression of BMP results in strong inhibition of FGF3 expression. Conversely, addition of follistatin leads to an increase in the level of FGF3 expression. Furthermore, the segmental inhibition of BMP activity by follistatin is required for the expression of Krox20, Hoxb1 and EphA4 in the hindbrain. In addition, we show that the maintenance of FGF3 gene expression requires FGF activity, suggestive of an autoregulatory loop. These results reveal an antagonistic relationship between BMP activity and FGF3 expression that is required for correct segmental gene expression in the chick hindbrain, in which follistatin enables FGF3 expression by inhibiting BMP activity.

Inhibition of BMPs by follistatin is required for FGF3 expression and segmental patterning of the hindbrain.

Il hindbrain vertebrati in via di sviluppo per la formazione e anteroposteriore patterning dei rhombomeres &egrave; necessaria una rete di interazioni molecolari. Segnalazione di FGF &egrave; necessaria in questa rete di potenziamento che l&#39;espressione di geni di segmentazione Krox20 e Kreisler, ma poco &egrave; noto di come espressione di gene FGF &egrave; regolata nel hindbrain. Ci mostra che l&#39;espressione dinamica di FGF3 in segmenti hindbrain pulcino e i confini &egrave; simile a quello dell&#39;antagonista BMP, follistatina. Coerente con un regolamentazione rapporto tra segnalazione BMP e FGF3 espressione, troviamo che un aumento nell&#39;attivit&agrave; BMP a causa di blocco di follistatina traduzione di oligonucleotidi antisense oligonucleotides o sovraespressione di BMP risultati in forte inibizione dell&#39;espressione FGF3. Al contrario, aggiunta di follistatina conduce ad un aumento del livello di espressione FGF3. Inoltre, l&#39;inibizione segmentaria dell&#39;attivit&agrave; BMP di follistatina &egrave; necessaria per l&#39;espressione di Krox20, Hoxb1 ed EphA4 nel hindbrain. Inoltre, ci mostrano che il mantenimento dell&#39;espressione del gene FGF3 richiede attivit&agrave; FGF, suggestiva di un ciclo di autoregulatory. Questi risultati rivelano un rapporto antagonistico tra attivit&agrave; BMP e FGF3 espressione che &egrave; necessaria per l&#39;espressione di gene corretto segmentale in hindbrain il pulcino, in espressione attiva FGF3 follistatina inibendo l&#39;attivit&agrave; BMP.

Inibizione di BMPs di follistatina &egrave; necessaria per FGF3 espressione e segmentale patterning del hindbrain.

During formation of the vertebrate central nervous system, the hindbrain is organized into segmental units, called rhombomeres (r). These cell-lineage restricted segments are separated by a subpopulation of cells known as boundary cells. Boundary cells display distinct molecular and cellular properties such as an elongated shape, enriched extracellular matrix components and a reduced proliferation rate compared to intra-rhombomeric cells. However, little is known regarding their functions and the mechanisms that regulate their formation.

Boundary cells regulate a switch in the expression of FGF3 in hindbrain rhombomeres.

Au cours de la formation du syst&egrave;me nerveux central vert&eacute;br&eacute;, le cerveau post&eacute;rieur est organis&eacute;e en unit&eacute;s segmentaires, appel&eacute;es rhombomeres (r). Ces segments de la lign&eacute;e cellulaire restreinte sont s&eacute;par&eacute;es par une sous-population de cellules appel&eacute;es cellules. Limite cellules affichent des propri&eacute;t&eacute;s mol&eacute;culaires et cellulaires distinctes comme une forme allong&eacute;e, constituants de la matrice extracellulaire enrichi et un taux de prolif&eacute;ration r&eacute;duite par rapport aux cellules intra-rhombomeric. Cependant, peu est connu au sujet de leurs fonctions et les m&eacute;canismes qui r&eacute;gulent leur formation.

Cellules r&eacute;glementent un commutateur dans l&#39;expression de FGF3 dans la rhombomeres du cerveau post&eacute;rieur.

Durante la formazione del sistema nervoso centrale vertebrato, il hindbrain &egrave; organizzato in unit&agrave; segmentali, denominato rhombomeres (r). Questi segmenti di cella-lignaggio limitato sono separati da una sottopopolazione di cellule conosciute come cellule di contorno. Le cellule contorno visualizzare propriet&agrave; molecolari e cellulari distinte come una forma allungata, componenti della matrice extracellulare arricchita e un tasso di proliferazione ridotta rispetto alle cellule intra-rhombomeric. Tuttavia, poco &egrave; noto riguardo le loro funzioni e dei meccanismi che regolano la loro formazione.

Le cellule limite regolano un interruttore nell&#39;espressione di FGF3 in hindbrain rhombomeres.

The locus coeruleus (LC) which is the major noradrenergic nucleus in the brain develops under the influence of Bmps secreted by the roof plate and Fgf8 emitted from the mid-hindbrain organizer. We studied the development of the LC in different Bmp mouse mutants and report the absence of this nucleus in Bmp5(-/-);Bmp7(-/-) double knockouts. Notably, genes marking organizers and neuronal populations adjacent to the LC precursor field are unperturbed in Bmp5(-/-);Bmp7(-/-) animals. In addition, we found that in En1(+/Otx2) mutants in which the caudal Otx2 expression domain and thereby the mid-hindbrain organizer are shifted caudally, LC neurons are concomitantly reduced along with Bmp5/7. Complementing these results, Otx1(-/-);Otx2(+/-) mutants, in which the mid-hinbrain organizer is shifted rostrally, show a rostrally extended Bmp5 expression area and an increase in LC neurons. Taken together, our data indicate that LC development requires either Bmp5 or Bmp7, and one is able to compensate for the loss of the other. In addition, we conclude that the position of the mid-hindbrain organizer determines the size of the LC and propose that Bmp5/7 play an important role in mediating this organizer function.

Bmp5/7 in concert with the mid-hindbrain organizer control development of noradrenergic locus coeruleus neurons.

Le locus coeruleus (LC) qui est le noyau noradr&eacute;nergique majeur dans le cerveau se d&eacute;veloppe sous l&#39;influence de PGB s&eacute;cr&eacute;t&eacute;e par la plaque de toit et Fgf8 &eacute;mise par l&#39;organisateur mid-hindbrain. Nous avons &eacute;tudi&eacute; le d&eacute;veloppement du code du travail dans diff&eacute;rents Bmp souris mutantes et signaler l&#39;absence de ce noyau en Bmp5(-/-) ;Bmp7(-/-) doubles entr&eacute;es d&eacute;fon&ccedil;ables. Notamment, les g&egrave;nes marquant les organisateurs et les populations neuronales adjacent au domaine de pr&eacute;curseur de LC sont non perturb&eacute;s en Bmp5(-/-) ;Bmp7(-/-) animaux. En outre, nous avons constat&eacute; que chez les mutants En1(+/Otx2) dans lequel le domaine d&#39;expression Otx2 caudal et ainsi l&#39;organisateur mid-hindbrain sont d&eacute;plac&eacute;s en direction caudale, neurones LC diminuent en m&ecirc;me temps avec Bmp5/7. En compl&eacute;ment de ces r&eacute;sultats, les mutants de la Otx1(-/-);Otx2(+/-), dans lequel l&#39;organisateur de la mi-hinbrain est d&eacute;cal&eacute; rostralement, montrent une zone d&#39;expression Bmp5 rostralement extension et une augmentation dans les neurones de la LC. Ensemble, nos donn&eacute;es indiquent que LC d&eacute;veloppement n&eacute;cessite soit Bmp5 ou Bmp7, et on est capable de compenser la perte de l&#39;autre. En outre, nous concluons que la position de l&#39;organisateur mid-hindbrain d&eacute;termine la taille du code du travail et de proposer que Bmp5/7 jouent un r&ocirc;le important dans la m&eacute;diation de cette fonction d&#39;organisateur.

Bmp5/7, de concert avec le d&eacute;veloppement de contr&ocirc;le mid-hindbrain organisateur de neurones du noradr&eacute;nergique locus coeruleus.

Il locus coeruleus (LC) che &egrave; il principale nucleo noradrenergico nel cervello si sviluppa sotto l&#39;influenza di Bmps secernuti dalla piastra di tetto e Fgf8 emesso dall&#39;Organizzatore mid-hindbrain. Abbiamo studiato lo sviluppo di LC in diversi mutanti di topo Bmp e segnalare l&#39;assenza di questo nucleo in Bmp5(-/-);Bmp7(-/-) doppio Knockout. In particolare, i geni marcatura organizzatori e popolazioni neuronali adiacenti al campo LC precursore sono imperturbate in Bmp5(-/-);Bmp7(-/-) animali. Inoltre, abbiamo scoperto che En1(+/Otx2) mutanti in cui il dominio di espressione Otx2 caudale e quindi l&#39;Organizzatore mid-hindbrain sono spostato caudalmente, neuroni LC sono simultaneamente ridotto insieme Bmp5/7. A complemento di questi risultati, Otx1(-/-);Otx2(+/-) mutanti, in cui &egrave; spostata rostralmente, organizzatore della met&agrave;-hinbrain Visualizza una area di espressione Bmp5 rostralmente estesa e un aumento in neuroni di LC. Presi insieme, i nostri dati indicano che LC sviluppo richiede Bmp5 o Bmp7, e uno &egrave; in grado di compensare la perdita di altro. Inoltre, concludiamo che la posizione dell&#39;organizzatore del mid-hindbrain determina la dimensione del LC e proporre che Bmp5/7 gioca un ruolo importante nella mediazione di questa funzione di organizzatore.

Bmp5/7 in concerto con lo sviluppo del controllo mid-hindbrain Organizzatore dei neuroni di noradrenergico locus coeruleus.

The development of the vertebrate hindbrain requires multiple coordinated signals which act via several pathways. One such signal is Fibroblast Growth Factor (FGF), which is necessary for the patterning of a major transcription factor in the hindbrain, Krox20. However, in the chick, it is still not known which specific FGF ligand is responsible for the regulation of Krox20 and how the signal is dispatched. The most characterized signaling pathway which FGF acts through in the nervous system is the MAPK/Erk1/2 pathway. Nevertheless, a detailed analysis of the hindbrain distribution of various components of this pathway has not been fully described. In this study we present a comprehensive atlas of the FGF ligands, receptors and members of the MAPK/Erk1/2 signaling components in subsequent stages of avian hindbrain development. Moreover, we show that FGF is a major signaling pathway that contributes to the activation of ERK1/2 and expression of the downstream targets Pea3 and Erm. Central to this study, we provide multiple evidence that FGF3 is required for the upregulation of Pea3 that in turn is necessary for Krox20 distribution in rhombomeres 3 and 5. These results show for the first time that Pea3 mediates the FGF3 signal to regulate the hindbrain expression of Krox20.

Analysis of expression and function of FGF-MAPK signaling components in the hindbrain reveals a central role for FGF3 in the regulation of Krox20, mediated by Pea3.

Le d&eacute;veloppement du rhombenc&eacute;phale vert&eacute;br&eacute; n&eacute;cessite plusieurs signaux coordonn&eacute;s qui agissent par l&#39;interm&eacute;diaire de plusieurs voies. Un tel signal est facteur de croissance fibroblastique (FGF), qui est n&eacute;cessaire pour la structuration d&#39;un facteur de transcription majeur dans le cerveau post&eacute;rieur, Krox20. Toutefois, dans le poussin, on est toujours sait pas quel ligand sp&eacute;cifique de FGF est responsable de la r&eacute;glementation des Krox20 et comment le signal est distribu&eacute;. La voie de signalisation plus caract&eacute;ris&eacute;e qui FGF agit par l&#39;interm&eacute;diaire du syst&egrave;me nerveux est la voie MAPK/Erk1/2. N&eacute;anmoins, une analyse d&eacute;taill&eacute;e de la distribution du cerveau post&eacute;rieur des diverses composantes de cette voie n&#39;a pas &eacute;t&eacute; enti&egrave;rement d&eacute;crit. Dans cette &eacute;tude, nous pr&eacute;sentons un atlas complet des ligands FGF, r&eacute;cepteurs et membres des composantes signalisation MAPK/Erk1/2 dans les &eacute;tapes ult&eacute;rieures du d&eacute;veloppement du cerveau post&eacute;rieur aviaire. En outre, nous montrons que la FGF est une voie de signalisation majeure qui contribue &agrave; l&#39;activation de ERK1/2 et l&#39;expression des objectifs en aval Pea3 et Erm. Centre de cette &eacute;tude, nous fournissons plusieurs preuves que FGF3 est requis pour l&#39;upregulation de Pea3 qui &agrave; son tour est n&eacute;cessaire pour la distribution de Krox20 dans rhombomeres 3 et 5. Ces r&eacute;sultats d&eacute;montrent pour la premi&egrave;re fois que Pea3 intervient dans le signal de FGF3 pour r&eacute;guler l&#39;expression de cerveau post&eacute;rieur de Krox20.

Analyse de l&#39;expression et la fonction des &eacute;l&eacute;ments de signalisation FGF-MAPK dans le cerveau post&eacute;rieur r&eacute;v&egrave;lent un r&ocirc;le central pour FGF3 dans la r&eacute;gulation de Krox20, m&eacute;di&eacute;e par Pea3.

Lo sviluppo del hindbrain vertebrati richiede pi&ugrave; segnali coordinati che agiscono tramite diversi percorsi. Un tale segnale &egrave; Fibroblast Growth Factor (FGF), che &egrave; necessario per la modellatura di un fattore di trascrizione importante in hindbrain, Krox20. Tuttavia, nel pulcino, non &egrave; ancora noto quale specifico ligando FGF &egrave; responsabile per la regolazione della Krox20 e come viene inviato il segnale. La via di segnalazione pi&ugrave; caratterizzata che FGF agisce attraverso il sistema nervoso &egrave; la via MAPK/Erk1/2. Tuttavia, un&#39;analisi dettagliata della distribuzione del hindbrain di vari componenti di questo percorso non &egrave; stato completamente descritto. In questo studio presentiamo un atlante completo dei ligandi FGF, recettori e dei membri delle componenti di segnalazione MAPK/Erk1/2 nelle fasi successive dello sviluppo hindbrain aviaria. Inoltre, mostriamo che FGF &egrave; un&#39;importante via di segnalazione che contribuisce per l&#39;attivazione di ERK1/2 e l&#39;espressione degli obiettivi a valle Pea3 ed Erm. Centrale di questo studio, forniamo prove multiple che FGF3 &egrave; richiesto per la sovraregolazione di Pea3 che a sua volta &egrave; necessario per la distribuzione di Krox20 in rhombomeres 3 e 5. Questi risultati dimostrano per la prima volta che Pea3 da intermediario il segnale FGF3 per regolare l&#39;espressione di hindbrain di Krox20.

Analisi di espressione e la funzione di segnalazione componenti FGF-MAPK nel hindbrain rivela un ruolo centrale per FGF3 nella regolazione del Krox20, mediata da Pea3.

This study determined the role of MMP9/gelatinase B during the migration onset of Neural Crest Cells (NCC) in avian embryos. NCC are neuroepithelial progenitors that convert into mesenchyme and migrate along defined paths throughout the embryo. To engage in migration, NCC loose cell contacts, detach from the neural tube and invade the surrounding environment. Multiple signals and transcription factors that regulate these events have been identified. Nevertheless, little is known regarding effectors that act downstream to execute the actual NCC migration. Matrix metalloproteinases (MMPs) compose a large family of enzymes whose principal substrates are basement membranes, adhesion proteins and the extracellular matrix (ECM) components. A major subgroup of MMPs, the gelatinases (MMP9 and 2) are central to many adult physiological and pathological processes, such as tumor metastasis and angiogenesis, in which cell-cell and cell-matrix contacts are degraded to allow migration. As NCC undergo similar processes during development, we hypothesized that MMP9 may also promote the migration of NCC. MMP9 was found to be expressed in delaminating and migrating NCC of both cranial and trunk axial levels. Blocking MMP9 resulted in a dramatic inhibition of NCC delamination and migration, without perturbing specification or survival. This inhibition occurred at regions containing both premigratory and migrating cells, indicative for the central role of MMP9 in executing the detachment of NCC from the neural tube as well as their migration. Conversely, excess MMP9 enhanced mesenchymalization and delamination of NCC and accelerated progenitors to undergo precocious migration. Examination of the mechanistic activity of MMP9 revealed its capability to degrade the adhesion molecule N-cadherin as well as the basement-membrane protein laminin within or around NCC, respectively. Altogether, our study reveals MMP9 as a novel effector which is required for NCC delamination and migration.

Matrix metalloproteinase 9/gelatinase B is required for neural crest cell migration.

Cette &eacute;tude a d&eacute;termin&eacute; le r&ocirc;le de MMP9/g&eacute;latinase B durant le d&eacute;but de la migration de cellules sur la cr&ecirc;te neurale (CNC) dans les embryons aviaires. NCC sont neuro&eacute;pith&eacute;liales prog&eacute;niteurs qui convertissent en m&eacute;senchyme et migrent le long des chemins d&eacute;finis tout au long de l&#39;embryon. Pour entreprendre une migration, contacts de cellule l&acirc;che NCC, d&eacute;tacher du tube neural et envahir le milieu environnant. Plusieurs signaux et des facteurs de transcription qui r&eacute;gissent ces &eacute;v&eacute;nements ont &eacute;t&eacute; identifi&eacute;s. N&eacute;anmoins, peu est connu au sujet des effecteurs qui agissent en aval pour ex&eacute;cuter la migration r&eacute;elle de la NCC. M&eacute;talloprot&eacute;inases matricielles (MMP) forment une grande famille d&#39;enzymes dont les principaux substrats sont des membranes basales, prot&eacute;ines d&#39;adh&eacute;sion et les composants de la matrice extracellulaire (ECM). Un sous-groupe important des MPM, les g&eacute;latinases (MMP9 et 2) sont au c&oelig;ur de nombreux processus physiologiques et pathologiques adultes, tels que les m&eacute;tastases tumorales et angiogen&egrave;se, dans quelle cellule-cellule et cellule-matrice, les contacts sont d&eacute;grad&eacute;es pour permettre la migration. Comme NCC subissent des processus semblables au cours du d&eacute;veloppement, nous avons &eacute;mis l&#39;hypoth&egrave;se que MMP9 peut aussi favoriser la migration de la NCC. MMP9 a &eacute;t&eacute; trouv&eacute; &agrave; s&#39;exprimer dans le NCC d&eacute;lamination et migration des deux cr&acirc;nienne et niveaux axial de tronc. Blocage MMP9 a entra&icirc;n&eacute; une inhibition dramatique de d&eacute;collement de la NCC et migration, sans sp&eacute;cification perturbante ou de survie. Cette inhibition est survenu r&eacute;gions contenant des cellules pr&eacute;-migratoires et de migration, indicatives pour le r&ocirc;le central de MMP9 qu&#39;impliquent le d&eacute;tachement de CCN du tube neural, mais aussi leur migration. &Agrave; l&#39;inverse, exc&egrave;s MMP9 am&eacute;lior&eacute; mesenchymalization et la d&eacute;lamination de la NCC et acc&eacute;l&eacute;r&eacute;e de prog&eacute;niteurs pour subir une migration pr&eacute;coce. L&#39;examen de l&#39;activit&eacute; m&eacute;canistique de MMP9 a r&eacute;v&eacute;l&eacute; sa capacit&eacute; &agrave; d&eacute;grader la mol&eacute;cule d&#39;adh&eacute;rence N-cadh&eacute;rine ainsi que la membrane basale prot&eacute;ine laminin dans ou autour de NCC, respectivement. Au total, notre &eacute;tude r&eacute;v&egrave;le MMP9 un effecteur roman qui est requis pour la migration et la d&eacute;lamination de la NCC.

Matrice m&eacute;talloprot&eacute;inase 9/g&eacute;latinase B est requis pour la migration des cellules neurales de cr&ecirc;te.

Questo studio ha determinato il ruolo di MMP9/gelatinasi B durante l&#39;insorgenza di migrazione della cresta neurale cellule (NCC) in embrioni aviari. NCC sono progenitori neuroepithelial che convertono in mesenchima e migrano lungo percorsi definiti in tutto l&#39;embrione. Per impegnarsi in migrazione, contatti allentati cella NCC, staccare dal tubo neurale e invadere l&#39;ambiente circostante. Sono stati identificati diversi segnali e fattori di trascrizione che regolano questi eventi. Tuttavia, poco &egrave; noto riguardo effettori che agiscono a valle per eseguire la migrazione di NCC effettiva. Metalloproteinasi della matrice (MMP) compongono una grande famiglia di enzimi cui substrati principali sono membrane basali, proteine di adesione e i componenti della matrice extracellulare (ECM). Un importante sottogruppo di MMP, il gelatinases (MMP9 e 2) sono al centro di molti adulti processi fisiologici e patologici, come metastasi tumorali e l&#39;angiogenesi, in cui la cellula-cellula e cellula-matrice contatti vengono degradati per consentire la migrazione. Come NCC subiscono processi simili durante lo sviluppo, abbiamo ipotizzato che MMP9 possono anche promuovere la migrazione di NCC. MMP9 &egrave; stato trovato per essere espresso in NCC delaminazioni e migrazione di entrambi craniale e livelli di assiale del tronco. Blocco MMP9 ha provocato una drammatica inibizione di delaminazione NCC e migrazione, senza specificazione perturbante o di sopravvivenza. Questa inibizione si &egrave; verificato alle regioni contenenti cellule sia premigratory e migrazione, indicative per il ruolo centrale di MMP9 in esecuzione il distaccamento di NCC dal tubo neurale, come pure la loro migrazione. Al contrario, eccesso MMP9 enhanced mesenchymalization e delaminazione di NCC e accelerato progenitori per subire un precoce migrazione. Esame dell&#39;attivit&agrave; meccanicistica di MMP9 ha rivelato la sua capacit&agrave; di degradare la molecola di adesione N-caderina, come pure la membrana basale della proteina laminina all&#39;interno o nei dintorni di NCC, rispettivamente. Complessivamente, il nostro studio rivela MMP9 come un romanzo effettrici che sono necessario per la migrazione e delaminazione NCC.

Matrix metalloproteinase 9/gelatinasi B &egrave; necessario per la migrazione cellulare cresta neurale.

Hindbrain dorsal interneurons that comprise the rhombic lip relay sensory information and coordinate motor outputs. The progenitor dA1 subgroup of interneurons, which is formed along the dorsal-most region of the caudal rhombic lip, gives rise to the cochlear and precerebellar nuclei. These centers project sensory inputs toward upper-brain regions. The fundamental role of dA1 interneurons in the assembly and function of these brainstem nuclei is well characterized. However, the precise en route axonal patterns and synaptic targets of dA1 interneurons are not clear as of yet. Novel genetic tools were used to label dA1 neurons and trace their axonal trajectories and synaptic connections at various stages of chick embryos. Using dA1-specific enhancers, two contralateral ascending axonal projection patterns were identified; one derived from rhombomeres 6-7 that elongated in the dorsal funiculus, while the other originated from rhombomeres 2-5 and extended in the lateral funiculus. Targets of dA1 axons were followed at later stages using PiggyBac-mediated DNA transposition. dA1 axons were found to project and form synapses in the auditory nuclei and cerebellum. Investigation of mechanisms that regulate the patterns of dA1 axons revealed a fundamental role of Lim-homeodomain (HD) proteins. Switch in the expression of the specific dA1 Lim-HD proteins Lhx2/9 into Lhx1, which is typically expressed in dB1 interneurons, modified dA1 axonal patterns to project along the routes of dB1 subgroup. Together, the results of this research provided new tools and knowledge to the assembly of trajectories and connectivity of hindbrain dA1 interneurons and of molecular mechanisms that control these patterns.

Axonal patterns and targets of dA1 interneurons in the chick hindbrain.

Les interneurones dorsales post&eacute;rieur qui composent la l&egrave;vre rhombique relaient les informations sensorielles et coordonnent les sorties moteurs. Le sous-groupe de dA1 prog&eacute;nitrices des interneurones, lequel est form&eacute; le long de la r&eacute;gion dorsale de la l&egrave;vre rhombique caudale, donne naissance aux noyaux cochl&eacute;aires et precerebellar. Ces centres du projet des inputs sensoriels vers les r&eacute;gions sup&eacute;rieures du cerveau. Le r&ocirc;le fondamental des interneurones dA1 dans l&#39;Assembl&eacute;e et la fonction de ces noyaux du tronc c&eacute;r&eacute;bral sont bien caract&eacute;ris&eacute;es. Cependant, les mod&egrave;les d&#39;axonales en route pr&eacute;cis et les cibles synaptiques des interneurones dA1 ne sont pas clairs pour le moment. Nouveaux outils g&eacute;n&eacute;tiques ont &eacute;t&eacute; utilis&eacute;es &agrave; &eacute;tiqueter dA1 neurones et tracer leurs trajectoires axonales et les connexions synaptiques &agrave; divers stades d&#39;embryons de poulets. &Agrave; l&#39;aide d&#39;exhausteurs de dA1 sp&eacute;cifique, deux controlat&eacute;rale croissant de mod&egrave;les de projection axonale ont &eacute;t&eacute; identifi&eacute;es ; un d&eacute;riv&eacute; rhombomeres 6-7 qui s&#39;allongent dans le funicule dorsal, tandis que les autres provenaient de rhombomeres 2-5 et prorog&eacute; depuis lors par le funicule lat&eacute;ral. Cibles des axones dA1 suivaient &agrave; un stade ult&eacute;rieur &agrave; l&#39;aide de la transposition de l&#39;ADN induite par le PiggyBac. dA1 axones trouv&eacute;es au projet et forme de synapses dans les noyaux auditifs et le cervelet. Les m&eacute;canismes qui r&eacute;gulent les patrons des axones dA1 a r&eacute;v&eacute;l&eacute; un r&ocirc;le fondamental des prot&eacute;ines Lim-hom&eacute;odomaine (HD). Commutateur dans l&#39;expression des prot&eacute;ines sp&eacute;cifiques dA1 Lim-HD Lhx2/9 le Lhx1, qui est g&eacute;n&eacute;ralement exprim&eacute;e en interneurones dB1, modifi&eacute;e dA1 axonale patrons pour projeter le long des routes du sous-groupe dB1. Ensemble, les r&eacute;sultats de cette recherche fournissent de nouveaux outils et connaissances &agrave; l&#39;Assembl&eacute;e de trajectoires et de la connectivit&eacute; des interneurones dA1 cerveau post&eacute;rieur et des m&eacute;canismes mol&eacute;culaires qui r&eacute;gissent ces patrons.

Mod&egrave;les axonales et cibles des interneurones dA1 dans le cerveau post&eacute;rieur de poussin.

Interneurons dorsale hindbrain che compongono il labbro rombico rel&egrave; informazioni sensoriali e coordinare uscite motore. Il sottogruppo di dA1 progenitore dei interneurons, che si forma lungo la regione pi&ugrave; dorsale del labbro rombico caudale, d&agrave; origine ai nuclei cocleari e precerebellar. Questi centri di progetto input sensoriali verso regioni del cervello superiore. Il ruolo fondamentale di dA1 interneurons in Assemblea e la funzione di questi nuclei del tronco encefalico &egrave; ben caratterizzate. Tuttavia, la precise rotta modelli assonale e bersagli sinaptici di dA1 interneurons non sono chiari ancora. Nuovi strumenti genetici sono stati utilizzati per etichettare i neuroni dA1 e tracciare le traiettorie assonale e connessioni sinaptiche nelle varie fasi di embrioni di pulcino. Utilizzando specifici dA1 esaltatori, due controlaterale ascendente modelli di proiezione assonale sono state identificate; una derivata da rhombomeres 6-7 che allungata il funiculus dorsale, mentre gli altri originati da rhombomeres 2-5 ed estesa nel funiculus laterale. Gli obiettivi degli assoni dA1 furono seguiti nelle fasi successive utilizzando la trasposizione del DNA mediata da PiggyBac. dA1 assoni sono stati trovati a progetto e forma sinapsi nel cervelletto e nuclei uditivi. Indagine dei meccanismi che regolano i modelli degli assoni dA1 ha rivelato un ruolo fondamentale delle proteine Lim-homeodomain (HD). Interruttore nell&#39;espressione di proteine specifiche dA1 Lim-HD Lhx2/9 in Lhx1, che &egrave; in genere espressa in dB1 interneurons, modificata dA1 assonale modelli di progetto lungo le rotte del sottogruppo dB1. Insieme, i risultati di questa ricerca forniti nuovi strumenti e conoscenze per l&#39;assemblaggio di traiettorie e connettivit&agrave; dei interneurons dA1 hindbrain e dei meccanismi molecolari che controllano questi modelli.

Modelli assonale e obiettivi di dA1 interneurons in hindbrain il pulcino.

The lack of affordable techniques for gene transfer in birds has inhibited the advancement of molecular studies in avian species. Here we demonstrate a new approach for introducing genes into chicken somatic tissues by administration of a lentiviral vector, derived from the feline immunodeficiency virus (FIV), into the chorioallantoic membrane (CAM) of chick embryos on embryonic day 11. The FIV-derived vectors carried yellow fluorescent protein (YFP) or recombinant alpha-melanocyte-stimulating hormone (Î±-MSH) genes, driven by the cytomegalovirus (CMV) promoter. Transgene expression, detected in chicks 2 days after hatch by quantitative real-time PCR, was mostly observed in the liver and spleen. Lower expression levels were also detected in the brain, kidney, heart and breast muscle. Immunofluorescence and flow cytometry analyses confirmed transgene expression in chick tissues at the protein level, demonstrating a transduction efficiency of âˆ¼0.46% of liver cells. Integration of the viral vector into the chicken genome was demonstrated using genomic repetitive (CR1)-PCR amplification. Viability and stability of the transduced cells was confirmed using terminal deoxynucleotidyl transferase (dUTP) nick end labeling (TUNEL) assay, immunostaining with anti-proliferating cell nuclear antigen (anti-PCNA), and detection of transgene expression 51 days post transduction. Our approach led to only 9% drop in hatching efficiency compared to non-injected embryos, and all of the hatched chicks expressed the transgenes. We suggest that the transduction efficiency of FIV vectors combined with the accessibility of the CAM vasculature as a delivery route comprise a new powerful and practical approach for gene delivery into somatic tissues of chickens. Most relevant is the efficient transduction of the liver, which specializes in the production and secretion of proteins, thereby providing an optimal target for prolonged study of secreted hormones and peptides.

Gene transfer to chicks using lentiviral vectors administered via the embryonic chorioallantoic membrane.

L&#39;absence de techniques abordables pour le transfert de g&egrave;nes chez les oiseaux a inhib&eacute; l&#39;avancement des &eacute;tudes mol&eacute;culaires chez les esp&egrave;ces aviaires. Nous d&eacute;montrons une nouvelle approche pour introduire des g&egrave;nes dans les tissus somatiques de poulet par l&#39;administration d&#39;un vecteur lentiviral, d&eacute;riv&eacute; du virus de l&#39;immunod&eacute;ficience f&eacute;line (FIV), dans la membrane Chorio-(CAM) des embryons de poulets embryonnaires jour 11. Les vecteurs d&eacute;riv&eacute;s FIV faite prot&eacute;ine fluorescente jaune (YFP) ou des recombinants alpha-melanocyte-stimulating hormone (&alpha;-MSH) g&egrave;nes, pilot&eacute;es par le promoteur du cytom&eacute;galovirus (CMV). Expression du transg&egrave;ne, d&eacute;tect&eacute;e chez les poussins 2 jours apr&egrave;s l&#39;&eacute;closion par PCR quantitative en temps r&eacute;el a &eacute;t&eacute; principalement observ&eacute;e dans le foie et la rate. Des niveaux inf&eacute;rieurs d&#39;expression ont aussi &eacute;t&eacute; d&eacute;tect&eacute;s dans le cerveau, rein, c&oelig;ur et poitrine de muscle. Immunofluorescence et &eacute;coulement cytometry analyses confirment transgene expression dans les tissus de poussin au niveau prot&eacute;ine, d&eacute;montrant une efficacit&eacute; de transduction de &sim;0.46 % des cellules du foie. Int&eacute;gration du vecteur viral dans le g&eacute;nome du poulet a &eacute;t&eacute; d&eacute;montr&eacute;e &agrave; l&#39;aide de g&eacute;nomique r&eacute;p&eacute;titives (CR1)-amplification par PCR. Viabilit&eacute; et la stabilit&eacute; des cellules transduits a &eacute;t&eacute; confirm&eacute;e &agrave; l&#39;aide de terminale de deoxynucleotidyl fin de nick transf&eacute;rase (dUTP) essai (TUNEL), immunomarquage avec anti-prolif&eacute;rant cell nuclear antigen (anti-PCNA) et la d&eacute;tection de transgene expression 51 jours post transduction d&#39;&eacute;tiquetage. Notre approche entra&icirc;nent seulement 9 % baisse l&#39;&eacute;closion de rendement par rapport aux embryons non inject&eacute;s, et tous les poussins &eacute;clos exprim&eacute; les transg&egrave;nes. Nous sugg&eacute;rons que l&#39;efficacit&eacute; de la transduction des vecteurs FIV combin&eacute;e avec l&#39;accessibilit&eacute; de la vascularisation de la CAM comme un itin&eacute;raire de livraison constituent une nouvelle approche puissante et pratique pour la livraison de g&egrave;ne dans les tissus somatiques des poulets. Plus pertinente est la transduction efficace du foie, qui se sp&eacute;cialise dans la production et la s&eacute;cr&eacute;tion de prot&eacute;ines, offrant ainsi une cible optimale pour une &eacute;tude prolong&eacute;e des hormones s&eacute;cr&eacute;t&eacute;es et des peptides.

Transfert de g&egrave;nes aux oisillons &agrave; l&#39;aide de vecteurs LENTIVIRAUX, administr&eacute;s par l&#39;interm&eacute;diaire de la membrane Chorio-embryonnaire.

La mancanza di conveniente tecniche di trasferimento genico in uccelli ha inibito l&#39;avanzamento degli studi molecolari in specie aviarie. Qui mostriamo un nuovo approccio per l&#39;introduzione di geni nei tessuti somatici di pollo con la somministrazione di un vettore lentivirale, derivato dal virus dell&#39;immunodeficienza felina (FIV), nella membrana corio-allantoidea (CAM) di embrioni di pulcino embrionale giorno 11. I vettori derivati da FIV trasportato proteina fluorescente gialla (YFP) o ricombinanti alfa-melanocita-stimolante (&alpha;-MSH) ormone geni, guidati dal promotore citomegalovirus (CMV). Espressione del transgene, rilevato in pulcini 2 giorni dopo il tratteggio di PCR quantitativa in tempo reale, &egrave; stata osservata principalmente nel fegato e milza. Pi&ugrave; bassi livelli di espressione sono stati rilevati anche nel muscolo del seno, rene, cuore e cervello. Analisi di citometria a flusso e immunofluorescenza ha confermato l&#39;espressione del transgene nei tessuti pulcino a livello proteico, dimostrando un&#39;efficienza di trasduzione del &sim;0.46% delle cellule del fegato. Integrazione del vettore virale nel genoma del pollo &egrave; stata dimostrata utilizzando genomic ripetitivi (CR1)-amplificazione di PCR. Solidit&agrave; e stabilit&agrave; delle cellule trasdotte &egrave; stata confermata usando terminal deoxynucleotidyl transferase (dUTP) nick estremit&agrave; dosaggio (TUNEL), immunocolorazione con anti-proliferazione antigene nucleare delle cellule (anti-PCNA) e individuazione del transgene expression 51 giorni post trasduzione di etichettatura. Il nostro approccio ha portato a solo 9% drop in cova l&#39;efficienza rispetto agli embrioni non iniettato, e tutti i pulcini nati espresso i transgeni. Suggeriamo che l&#39;efficienza di trasduzione della FIV vettori combinato con l&#39;accessibilit&agrave; del sistema vascolare CAM come un itinerario di consegna comprendono un nuovo approccio pratico e potente per la consegna del gene nei tessuti somatici dei polli. Pi&ugrave; rilevante &egrave; la trasduzione efficiente del fegato, che &egrave; specializzata nella produzione e secrezione di proteine, fornendo in tal modo una destinazione ottimale per studio prolungato secrete ormoni e peptidi.

Trasferimento del gene per pulcini utilizzando vettori lentivirali somministrati attraverso la membrana corio-allantoidea embrionale.

Extracellular matrix mineralization is an essential physiologic process in bone, teeth, and hypertrophic cartilage. Matrix Gla protein (MGP), an inhibitor of mineralization, is expressed by chondrocytes and vascular smooth muscle cells to inhibit calcification of those soft tissues. Tibial dyschondroplasia (TD), a skeletal abnormality apparent as a plug of non-vascularized, non-mineralized, white opaque cartilage in the tibial growth plate of avian species can serve as a good model for studying process and genes involved in matrix mineralization and calcification. In this work, we studied the involvement of MGP in the development of TD, as well as in the processes of spontaneous and induced recovery from this syndrome. First, we found that during normal bone development, MGP is expressed in specific time and locations, starting from wide-spread expression in the yet un-ossified diaphysis during embryonic development, to specific expression in hypertrophic chondrocytes adjacent to the chondro-osseous junction and the secondary ossification center just prior to calcification. In addition, we show that MGP is not expressed in the impaired TD lesion, however when the lesion begins to heal, it strongly express MGP prior to its calcification. Moreover, we show that when calcification is inhibited, a gap is formed between the expression zones of MGP and BMP2 and that this gap is closed during the healing process. To conclude, we suggest that MGP, directly or through interaction with BMP2, plays a role as ossification regulator that acts prior to ossification, rather then simple inhibitor.

The role of matrix gla protein in ossification and recovery of the avian growth plate.

Min&eacute;ralisation de la matrice extracellulaire est un processus physiologique essentiel dans les dents, OS et cartilage hypertrophique. Gla prot&eacute;ine (MGP), un inhibiteur de la min&eacute;ralisation, s&#39;exprime par les chondrocytes et les cellules musculaires lisses vasculaires pour inhiber la calcification de ces tissus mous. Dyschondroplasie tibiale (TD), une anomalie squelettique apparente comme une fiche de non vascularis&eacute;, non min&eacute;ralis&eacute;e, blanc cartilage opaque dans la plaque de croissance tibial des esp&egrave;ces aviaires peut servir comme un bon mod&egrave;le pour &eacute;tudier les processus et les g&egrave;nes impliqu&eacute;s dans la calcification et la min&eacute;ralisation de la matrice. Dans ce travail, nous avons &eacute;tudi&eacute; l&#39;implication du projet gazier Mackenzie dans le d&eacute;veloppement de TD, ainsi que dans les processus de r&eacute;cup&eacute;ration spontan&eacute;e et induite de ce syndrome. Tout d&#39;abord, nous avons constat&eacute; qu&#39;au cours du d&eacute;veloppement de l&#39;os normal, MGP est exprim&eacute;e en temps et lieux, &agrave; partir de l&#39;expression r&eacute;pandue dans la diaphyse encore un-ossified durant le d&eacute;veloppement embryonnaire, &agrave; une expression sp&eacute;cifique dans les chondrocytes hypertrophiques adjacentes &agrave; la jonction chondro-osseuse et le centre d&#39;ossification secondaire juste avant la calcification. En outre, nous montrons que le PGM n&#39;est pas exprim&eacute;e dans la l&eacute;sion de TD avec facult&eacute;s affaiblies, mais lorsque la l&eacute;sion commence &agrave; gu&eacute;rir, c&#39;express fortement MGP avant sa calcification. En outre, nous montrons que lorsque la calcification est inhib&eacute;e, une lacune est form&eacute;e entre les zones d&#39;expression du MGP et BMP2 et que cet &eacute;cart est ferm&eacute; pendant le processus de gu&eacute;rison. Pour conclure, nous sugg&eacute;rons que le PGM, directement ou via l&#39;interaction avec la BMP2, joue un r&ocirc;le en tant que r&eacute;gulateur d&#39;ossification qui agit avant l&#39;ossification, plut&ocirc;t alors simple inhibiteur.

Le r&ocirc;le de matrice gla prot&eacute;ine ossification et le r&eacute;tablissement de la plaque de croissance aviaire.

Mineralizzazione della matrice extracellulare &egrave; un processo fisiologico essenziale in ossa, denti e cartilagine ipertrofica. Matrix Gla protein (MGP), un inibitore della mineralizzazione, &egrave; espressa dai condrociti e di cellule muscolari lisce vascolari per inibire la calcificazione di quelle dei tessuti molli. Dyschondroplasia tibia (TD), un&#39;anormalit&agrave; scheletriche apparente come una spina di non vascolarizzato, non mineralizzata, bianca opaca cartilagine nel piatto tibiale crescita delle specie aviaria pu&ograve; servire come un buon modello per lo studio di processo e geni coinvolti nella calcificazione e mineralizzazione della matrice. In questo lavoro, abbiamo studiato il coinvolgimento del MGP nello sviluppo del TD, cos&igrave; come nei processi di recupero spontaneo e indotto da questa sindrome. In primo luogo, abbiamo trovato che durante lo sviluppo normale delle ossa, MGP &egrave; espresso nel momento specifico e posizioni, a partire da espressione diffusa nella diafisi ancora un-ossified durante lo sviluppo embrionale, all&#39;espressione specifica in ipertrofica condrociti adiacenti per la giunzione condro-ossea e il centro di ossificazione secondario appena prima della calcificazione. Inoltre, mostriamo che MGP non &egrave; espresso nella lesione TD compromessa, tuttavia quando la lesione comincia a guarire, esprimere fortemente MGP prima della sua calcificazione. Inoltre, ci mostrano che quando la calcificazione &egrave; inibita, si forma un divario tra le zone di espressione del MGP e BMP2 e che questo divario &egrave; chiuso durante il processo di guarigione. Per concludere, consigliamo che MGP, direttamente o attraverso l&#39;interazione con BMP2, svolge un ruolo come regolatore di ossificazione che agisce prima dell&#39;ossificazione, piuttosto allora semplice inibitore.

Il ruolo della proteina gla matrix nel ripristino della piastra di crescita aviaria e ossificazione.

Compartment boundaries act as organizing centers that segregate adjacent areas into domains of gene expression and regulation, and control their distinct fates via the secretion of signalling factors. During hindbrain development, a specialized cell-population forms boundaries between rhombomeres. These boundary cells demonstrate unique morphological properties and express multiple genes that differs them from intra-rhombomeric cells. Yet, little is known regarding the mechanisms that controls the expression or function of these boundary markers.Multiple components of the FGF signaling system, including ligands, receptors, downstream effectors as well as proteoglycans are shown to localize to boundary cells in the chick hindbrain. These patterns raise the possibility that FGF signaling plays a role in regulating boundary properties. We provide evidence to the role of FGF signaling, particularly the boundary-derived FGF3, in regulating the expression of multiple markers at hindbrain boundaries. These findings enable further characterization of the unique boundary-cell population, and expose a new function for FGFs as regulators of boundary-gene expression in the chick hindbrain.

Expression of hindbrain boundary markers is regulated by FGF3.

Limites servent de centres que de s&eacute;parer les zones adjacentes dans les domaines de l&#39;expression g&eacute;nique et r&egrave;glement d&#39;organisation du compartiment et contr&ocirc;ler leur destin distinct par l&#39;interm&eacute;diaire de la s&eacute;cr&eacute;tion de facteurs de signalisation. Au cours du d&eacute;veloppement du cerveau post&eacute;rieur, une population de cellules sp&eacute;cialis&eacute;e forme fronti&egrave;re entre rhombomeres. Ces cellules montrent des propri&eacute;t&eacute;s morphologiques uniques et expriment des g&egrave;nes multiples qui eux diff&egrave;re des cellules intra-rhombomeric. Pourtant, on sait peu sur les m&eacute;canismes contr&ocirc;lant l&#39;expression ou la fonction de ces bornes.Plusieurs composants du syst&egrave;me, y compris les ligands, r&eacute;cepteurs, effecteurs en aval ainsi que des prot&eacute;oglycanes de signalisation FGF apparaissent &agrave; localiser les cellules dans le cerveau post&eacute;rieur de poussin. Ces mod&egrave;les soul&egrave;vent la possibilit&eacute; que le FGF signalisation joue un r&ocirc;le dans la r&eacute;gulation des propri&eacute;t&eacute;s de la limite. Nous fournissons des preuves du r&ocirc;le de FGF de signalisation, en particulier la limite d&eacute;riv&eacute;e FGF3, dans la r&eacute;gulation de l&#39;expression des marqueurs multiples aux limites du cerveau post&eacute;rieur. Ces constatations permettent davantage de caract&eacute;risation de la population de cellules limite unique et exposent une nouvelle fonction pour FGFs comme r&eacute;gulateurs d&#39;expression limite-g&egrave;ne dans le cerveau post&eacute;rieur de poussin.

Expression des marqueurs de limite de cerveau post&eacute;rieur est r&eacute;gul&eacute;e par FGF3.

Vano i confini atto come organizzare centri che segregano le zone adiacenti in domini di espressione genica e di regolamento e controllano i loro destini distinti tramite la secrezione di fattori di segnalazione. Durante lo sviluppo del hindbrain, una popolazione di cellule specializzata forma i confini tra rhombomeres. Queste cellule contorno dimostrano propriet&agrave; morfologiche uniche ed esprimono pi&ugrave; geni che li differisce dalle cellule intra-rhombomeric. Eppure, poco &egrave; noto riguardo i meccanismi che controlla l&#39;espressione o la funzione di questi marcatori di confine.Pi&ugrave; componenti di FGF segnalando il sistema, tra cui ligandi, i recettori, effettori a valle cos&igrave; come i proteoglicani sono mostrati da localizzare alle cellule contorno del hindbrain pulcino. Questi modelli di aumentare la possibilit&agrave; che FGF segnalando un ruolo nella regolazione della propriet&agrave; di contorno. Forniamo prove per il ruolo di FGF segnalando, particolarmente il confine-derivati FGF3, nel regolare l&#39;espressione di marcatori multipli presso i confini hindbrain. Questi risultati permettono ulteriore caratterizzazione della popolazione unico limite-cella ed espongono una nuova funzione per FGFs come regolatori di confine-gene expression in hindbrain il pulcino.

Espressione di marcatori di confine hindbrain &egrave; regolata da FGF3.

Neural crest cells (NCCs) migrate throughout the embryo to differentiate into cell types of all germ layers. Initial directed NCC emigration relies on planar cell polarity (PCP), which through the activity of the small GTPases RhoA and Rac governs the actin-driven formation of polarized cell protrusions. We found that the actin binding protein calponin 2 (Cnn2) was expressed in protrusions at the leading edge of migratory NCCs in chicks and frogs. Cnn2 knockdown resulted in NCC migration defects in frogs and chicks and randomized outgrowth of cell protrusions in NCC explants. Morphant cells showed central stress fibers at the expense of the peripheral actin network. Cnn2 acted downstream of Wnt/PCP, as migration defects induced by dominant-negative Wnt11 or inhibition of RhoA function were rescued by Cnn2 knockdown. These results suggest that Cnn2 modulates actin dynamics during NCC migration as an effector of noncanonical Wnt/PCP signaling.

Calponin 2 acts as an effector of noncanonical Wnt-mediated cell polarization during neural crest cell migration.

Migrent les cellules neurales de cr&ecirc;te (CNC) tout au long de l&#39;embryon se diff&eacute;rencier en types cellulaires de toutes les couches de germe. Initiale dirig&eacute;e de l&#39;&eacute;migration NCC s&#39;appuie sur la polarit&eacute; de cellule planaire (PCP), qui, par le biais de l&#39;activit&eacute; des petites GTPases RhoA et Rac, r&eacute;git la formation ax&eacute;e sur l&#39;actine de protub&eacute;rances cellule polaris&eacute;e. Nous avons trouv&eacute; que l&#39;actine liaison prot&eacute;ine calponine 2 (Cnn2) a &eacute;t&eacute; exprim&eacute;e en saillies &agrave; la fine pointe des migrateurs CNC de poussins et de grenouilles. Cnn2 knockdown a entra&icirc;n&eacute; NCC migration d&eacute;fauts de grenouilles et de poussins et d&#39;excroissance randomis&eacute;e de protub&eacute;rances cellulaires des explants de NCC. Morphant cellules des fibres de stress central a montr&eacute; au d&eacute;triment du r&eacute;seau d&#39;actine p&eacute;riph&eacute;rique. Cnn2 agi en aval de Wnt/PCP, migration, d&eacute;fauts induits par dominant n&eacute;gatif Wnt11 ou inhibition de la fonction de RhoA furent secourus par Cnn2 knockdown. Ces r&eacute;sultats sugg&egrave;rent que Cnn2 module dynamique de l&#39;actine au cours de la migration de la NCC comme effecteur de la signalisation Wnt/PCP non canonique.

2 La calponine agit comme un processeur d&#39;effets de polarisation cellulaire non canonique Wnt au cours de la migration des cellules neurales de cr&ecirc;te.

La migrazione di cellule della cresta neurale (CNC) in tutto l&#39;embrione a differenziarsi in tipi cellulari di tutti gli strati del germe. Iniziale dell&#39;emigrazione NCC diretto si basa sulla polarit&agrave; planare delle cellule (PCP), che attraverso l&#39;attivit&agrave; del piccolo GTPases RhoA e Rac governa la formazione guidata da actina di protrusioni cella polarizzata. Abbiamo trovato che l&#39;actina associazione proteina calponin 2 (Cnn2) &egrave; stata espressa in sporgenze all&#39;avanguardia di migratori CNC in pulcini e rane. Cnn2 atterramento provocato difetti di migrazione NCC in rane, pulcini e randomizzato escrescenza di protrusioni cellulari in NCC espianti. Morphant cellule ha mostrato lo stress centrale fibre a scapito della rete periferica dell&#39;actina. Cnn2 ha agito a valle di Wnt/PCP, come migrazione indotti da dominante negativo Wnt11 o inibizione della funzione RhoA difetti furono salvati da Cnn2 atterramento. Questi risultati suggeriscono che Cnn2 modula dinamiche di actina durante la migrazione di NCC come un effector di segnalazione Wnt/PCP canonica.

2 Calponin agisce come un generatore di effetti di polarizzazione canonica Wnt-mediata delle cellule durante la migrazione cellulare cresta neurale.

Des motifs complexes et des r&eacute;seaux de g&egrave;nes coordonnent les identit&eacute;s rhombomeric, segmentation du cerveau post&eacute;rieur et la diff&eacute;renciation neuronale et sont responsables de fonctions plus tard de tronc c&eacute;r&eacute;bral. Pax6 est un facteur de transcription hautement conserv&eacute;e crucial pour le d&eacute;veloppement neuronal, mais peu est connu au sujet de ses premiers r&ocirc;les au cours de la segmentation du cerveau post&eacute;rieur. Nous montrons que Pax6 expression est tr&egrave;s dynamique en rhombomeres, ce qui sugg&egrave;re une fonction pr&eacute;coce dans le cerveau post&eacute;rieur. Utilisation de multiples gain - et perte de fonction s&#39;approche en Poussin et souris a r&eacute;v&eacute;l&eacute; que la perte de Pax6 perturbe les fronti&egrave;res de la forte expression de Krox20, Kreisler, Hoxa2, Hoxb1 et EphA et conduit &agrave; leur expansion dans les territoires adjacents, tandis que les exc&egrave;s Pax6 r&eacute;duit ces domaines d&#39;expression. Une interf&eacute;rence n&eacute;gative mutuelle entre Pax6 et Krox20 permet ces g&egrave;nes d&#39;&ecirc;tre co-exprim&eacute;e dans le cerveau post&eacute;rieur par la r&eacute;gulation du g&egrave;ne Krox20-r&eacute;presseur Nab1 par Pax6. Rhombom&egrave;re limites sont aussi se d&eacute;former lors des manipulations de Pax6, sugg&eacute;rant un m&eacute;canisme par lequel Pax6 agit pour d&eacute;finir la segmentation du cerveau post&eacute;rieur. Enfin, FGF actes en amont du r&eacute;seau Pax6-Krox20 de signalisation pour r&eacute;guler l&#39;expression segmentaire Pax6. Cette &eacute;tude d&eacute;voile un nouveau r&ocirc;le pour Pax6 dans l&#39;organisation segmentaire de la cerveau post&eacute;rieur au d&eacute;but et fournit de nouvelles preuves de son importance dans l&#39;organisation r&eacute;gionale le long du syst&egrave;me nerveux central.

Un nouveau r&ocirc;le pour Pax6 dans l&#39;organisation segmentaire de la cerveau post&eacute;rieur.

Complex patterns and networks of genes coordinate rhombomeric identities, hindbrain segmentation and neuronal differentiation and are responsible for later brainstem functions. Pax6 is a highly conserved transcription factor crucial for neuronal development, yet little is known regarding its early roles during hindbrain segmentation. We show that Pax6 expression is highly dynamic in rhombomeres, suggesting an early function in the hindbrain. Utilization of multiple gain- and loss-of-function approaches in chick and mice revealed that loss of Pax6 disrupts the sharp expression borders of Krox20, Kreisler, Hoxa2, Hoxb1 and EphA and leads to their expansion into adjacent territories, whereas excess Pax6 reduces these expression domains. A mutual negative cross-talk between Pax6 and Krox20 allows these genes to be co-expressed in the hindbrain through regulation of the Krox20-repressor gene Nab1 by Pax6. Rhombomere boundaries are also distorted upon Pax6 manipulations, suggesting a mechanism by which Pax6 acts to set hindbrain segmentation. Finally, FGF signaling acts upstream of the Pax6-Krox20 network to regulate Pax6 segmental expression. This study unravels a novel role for Pax6 in the segmental organization of the early hindbrain and provides new evidence for its significance in regional organization along the central nervous system.

A novel role for Pax6 in the segmental organization of the hindbrain.

Modelli complessi e reti di geni coordinano rhombomeric identit&agrave;, hindbrain segmentazione e differenziazione neuronale e sono responsabili per le funzioni del tronco cerebrale pi&ugrave; tardi. PAX6 &egrave; un fattore di trascrizione altamente conservata cruciale per lo sviluppo neuronale, ancora poco si sa per quanto riguarda i suoi primi ruoli durante la segmentazione hindbrain. Mostriamo che espressione di Pax6 &egrave; altamente dinamico in rhombomeres, suggerendo una funzione precoce nel hindbrain. L&#39;utilizzo di pi&ugrave; guadagno e perdita-di-funzione si avvicina in pulcino e topi ha rivelato che la perdita di Pax6 sconvolge i bordi taglienti espressione di Krox20, Kreisler, Hoxa2, Hoxb1 ed EphA e porta alla loro espansione in territori adiacenti, mentre Pax6 in eccesso riduce questi domini di espressione. Un cross-talk negativo reciproco tra Pax6 e Krox20 permette di questi geni di essere espressi in hindbrain attraverso il regolamento del gene Krox20-repressor Nab1 di Pax6. Rhombomere confini sono distorte anche su manipolazioni Pax6, suggerendo un meccanismo mediante il quale Pax6 agisce per impostare segmentazione hindbrain. Infine, FGF atti a monte della rete Pax6-Krox20 di segnalazione per regolare espressione segmentale Pax6. Questo studio si dipana un nuovo ruolo per Pax6 nell&#39;organizzazione segmentale del hindbrain precoce e fornisce nuove prove per la sua importanza nell&#39;organizzazione regionale lungo il sistema nervoso centrale.

Article	Year
Localized BMP4-noggin interactions generate the dynamic patterning of noggin expression in somites. Developmental biology\| PubMed ID: 12051818	2002
Canonical Wnt activity regulates trunk neural crest delamination linking BMP/noggin signaling with G1/S transition. Development (Cambridge, England)\| PubMed ID: 15456730	2004
Eph receptors: two ways to sharpen boundaries. Current biology : CB\| PubMed ID: 15797015	2005
Inhibition of BMPs by follistatin is required for FGF3 expression and segmental patterning of the hindbrain. Developmental biology\| PubMed ID: 18823972	2008
Boundary cells regulate a switch in the expression of FGF3 in hindbrain rhombomeres. BMC developmental biology\| PubMed ID: 19232109	2009
Bmp5/7 in concert with the mid-hindbrain organizer control development of noradrenergic locus coeruleus neurons. Molecular and cellular neurosciences\| PubMed ID: 20493948	2010
Analysis of expression and function of FGF-MAPK signaling components in the hindbrain reveals a central role for FGF3 in the regulation of Krox20, mediated by Pea3. Developmental biology\| PubMed ID: 20553903	2010
Matrix metalloproteinase 9/gelatinase B is required for neural crest cell migration. Developmental biology\| PubMed ID: 22342386	2012
Axonal patterns and targets of dA1 interneurons in the chick hindbrain. The Journal of neuroscience : the official journal of the Society for Neuroscience\| PubMed ID: 22539838	2012
Gene transfer to chicks using lentiviral vectors administered via the embryonic chorioallantoic membrane. PloS one\| PubMed ID: 22606269	2012
The role of matrix gla protein in ossification and recovery of the avian growth plate. Frontiers in endocrinology\| PubMed ID: 22787455	2012
Expression of hindbrain boundary markers is regulated by FGF3. Biology open\| PubMed ID: 23213398	2012
Calponin 2 acts as an effector of noncanonical Wnt-mediated cell polarization during neural crest cell migration. Cell reports\| PubMed ID: 23499442	2013
A novel role for Pax6 in the segmental organization of the hindbrain. Development (Cambridge, England)\| PubMed ID: 23578930	2013

Dalit Sela-Donenfeld

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