Name: gene interaction maps in epistasis
Uploaded: 2023-04-30T10:14:33.000Z
Duration: 1 min 9 s
Channel: JoVE

İki gen arasındaki zıt bir ilişki, bir genin diğerinin ifadesini maskelediği veya değiştirdiği epistasistir. Etkileyen genin, maskelenen gene epistatik olduğu söylenir.
Örneğin, tirozinaz ile ilişkili protein 1'i veya TYRP1'i kodlayan bir gen, köpeklerin tüy rengini belirler - siyah veya kahverengi.
Başka bir gen olan Tyr, hayvanlarda pigmentasyondan sorumlu olan tirozinaz enzimini kodlar. Bu gendeki bir mutasyon, pigment yokluğuna neden olabilir ve bu da herhangi bir renklenme olmayan bir albino köpeğe neden olabilir.
Bu iki genin ifade edilme sırası bir epistasis testi ile belirlenebilir.
Tyr genindeki bir mutasyon, hala vahşi tip TYRP1 genine sahip bir albino köpek üretirse, Tyr geninin TYRP1 geninin etkisini maskelediği sonucuna varılabilir. Bu, Tyr'nin TYRP1'e epistatik olduğu anlamına gelir.

<ol>
	<li>Michels, C.A. (2002). Epistazi Analizi. Biyolojik Araştırma için Genetik Tekniklerde, C.A. Michels (Ed.). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf ve Richard E. Michod. "Genetik hasar, mutasyon ve cinsiyetin evrimi." Bilim 229, hayır. 4719 (1985): 1277-1281.</li>
</ol>

epistaz analizi

Epistasis Analysis

Her ne kadar Mendel bezelyelerde gen ayrımını incelemek için birbiriyle ilgisiz yedi özellik seçmiş olsa da, özelliklerin çoğu, bir fenotip spektrumu oluşturan çoklu gen etkileşimlerini içerir. Farklı konumlardaki çeşitli genlerin veya alellerin etkileşimi bir fenotipi etkilediğinde buna epistaz denir. Epistaz sıklıkla bir genin diğerinin ifadesini maskelemesini veya müdahale etmesini içerir (antagonistik epistaz). Epistaz sıklıkla farklı genler aynı biyokimyasal yolun parçası olduğunda ortaya çıkar. Bir genin ifadesi aynı biyokimyasal yoldaki bir gen ürününe bağlı olabilir. Epistatik analiz Epistatik etkileşimlerin incelenmesi, araştırmacıların genler arasındaki fonksiyonel ilişkiyi, genlerin bir yoldaki sıralamasını ve farklı alellerin fenotipleri niceliksel olarak nasıl etkilediğini belirlemesine olanak tanır. Farklı genler tarafından kodlanan birden fazla proteinin katalize ettiği biyokimyasal bir reaksiyonu düşünün. Bu tür biyokimyasal reaksiyonlarda yer alan genler, aynı biyokimyasal yola dahil olan diğer genleri maskeleyebilir veya inhibe edebilir; bu olaya epistaz adı verilir. Bu tür genlerin bir epistaz grubunda olduğu söylenir. Bilim insanları, farklı genler arasındaki epistatik ilişkiyi analiz ederek, bir yola dahil olan olayların ve genlerin sırasını gösteren bir işlev sırası haritası oluşturabilirler. Bu işleme epistatik analiz denir. Epistatik analiz için seçilen alellerin farklı fenotiplere sahip olması gerekir. Böylelikle, epistaz kavramının ortaya atılmasından bu yana, çoğu biyolojik sistemin birbiriyle çoklu ve karmaşık yollarla etkileşime giren birçok genetik öğeyi içerdiği giderek daha açık hale geldi.

Epistaz Analizi

Mendel, gen ayrışmasını incelemek için bezelyede yedi ilgisiz özellik seçmesine rağmen, çoğu özellik, bir spektrum oluşturan çoklu gen etkileşimlerini içerir ...

Education

JoVE Core

Molecular Biology

Moleküler Biyoloji

Unit 2

Ünite 2

Analyzing Gene Expression and Function

Gen İfadesinin ve İşlevinin Analizi

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

gene interaction maps in epistasis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene.

Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in the same pathway are considered part of one epistasis group.

Epistatic analysis uses these interactions to reveal how genes are related. Scientists can use it to identify the functional relationship between genes, determine the order of genes in a pathway, and see how different alleles affect phenotypes in a quantitative way. When multiple proteins encoded by different genes take part in a biochemical reaction, epistatic analysis can help build an order-of-function map that shows the sequence of events and the genes involved.

To compare genes in this way, the alleles chosen for analysis must have distinct phenotypes. Since epistasis was first described, it has become clear that many biological systems include genetic elements that interact in complex ways. These interactions help explain why many traits do not follow simple single-gene patterns.

Gene Interaction Maps in Epistasis

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RNAi for Gene Silencing and Discovery

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transgenic plants

Transgenic Plants for Better Crops

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epistasis analysis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene. Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in...

genome-wide association studies-gwas

Using SNP Patterns to Link Disease Risk

Genome-wide association studies, or GWAS, look for common SNPs, or single nucleotide polymorphisms, that may be linked to disease. Researchers compare how often a SNP appears in people with a disease and in people without it. When a SNP is seen more often in the disease group, it is considered associated with that disease. GWAS uses chi-square analysis to test the chance that an allele is linked to the disease. This approach does not require scientists to first find the target gene behind the...

key terms and concepts

Explore how epistasis reveals gene interactions, pathway order, and phenotype changes through epistatic analysis in high school biology.

Gene Interaction Maps in Epistasis | JoVE K12

molecular biology

JoVE Core Moleküler Biyoloji, hücrenin moleküler süreçlerini açık ve özlü animasyonlu video dersleriyle sergiler. Buna ek olarak, bilim insanı-eylem videolarında, bu kavramların uygulaması modern laboratuvarlarda gerçek deneylerle gösterilmektedir.

Gene Interaction Maps in Epistasis

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