Name: desmosomes and cell anchoring
Uploaded: 2025-05-22T09:05:46.000Z
Duration: 1 min 5 s
Channel: JoVE

Los desmosomas son uniones de anclaje que se encuentran más abundantemente en los tejidos que experimentan estrés mecánico, como el músculo cardíaco y el epitelio intestinal.
La adhesión celular en los desmosomas se ve facilitada por las cadherinas desmosómicas, a saber, la desmocolina y la desmogleína, que se adhieren a través de interacciones heterofílicas de sus dominios extracelulares.
El dominio citoplasmático de las cadherinas se une a las cateninas llamadas plakoglobinas y placofilinas, que forman una placa densa en el lado citoplasmático.
Las cateninas no pueden unirse directamente a los filamentos intermedios y se unen a ellos mediante la desmoplaquina, una proteína enlazadora del citoesqueleto que pertenece a la familia de las plakinas.
El dominio N-terminal de la desmoplaquina se une a las cateninas, y sus repeticiones de plakin C-terminal se unen a los filamentos intermedios.
Así, el desmosoma, ancla los filamentos intermedios de las células adyacentes, formando una red de citoesqueletos transcelulares a través del tejido.

<ol>
	<li>Delva, Emmanuella, Dana K. Tucker y Andrew P. Kowalczyk. "El desmosoma". Perspectivas de Cold Spring Harbor en biología 1.2 (2009): a002543.</li>
	<li>Garrod, David y Martyn Chidgey. "Estructura, composición y función del desmosoma". Biochimica et Biophysica Acta (BBA)-Biomembranes 1778.3 (2008): 572-587.</li>
	<li>Nekrasova, Oxana y Kathleen J. Green. "Ensamblaje y dinámica de Desmosoma". Tendencias en biología celular 23.11 (2013): 537-546.</li>
</ol>

desmosomas

Desmosomes

El término desmosoma deriva de las palabras griegas "desmo" y "soma", que significan "cuerpos de adhesión". Esta estructura se observó por primera vez a finales del siglo XIX y se describió como nódulos pequeños y densos en la epidermis. Los desmosomas son estructuras en forma de botones que ayudan a formar una red interconectada de filamentos intermedios a lo largo de las células. Estas uniones son esenciales para mantener unidas las células bajo tensión mecánica y mantener la integridad del tejido. Los desmosomas son complejos multiproteicos que comprenden cadherinas desmosómicas que están unidas a filamentos intermedios mediante varias proteínas adaptadoras.

Cadherinas desmosómicas

Las cadherinas forman la región central extracelular de un desmosoma y se unen a las cadherinas de la célula adyacente. Hay dos tipos de cadherinas en los desmosomas: desmogleínas y desmocolinas. Estas glicoproteínas transmembrana poseen una gran porción extracelular que comprende cuatro repeticiones de cadherina y un dominio de anclaje extracelular que ancla estas proteínas a la membrana celular. Los pares heterodiméricos de desmogleínas y desmocolinas forman grupos mediante interacciones cis en la misma célula e interacciones trans entre células adyacentes. Sus dominios citoplasmáticos pueden variar en longitud entre las diferentes isoformas debido al empalme alternativo; por ejemplo, hay cuatro isoformas de desmogleína y tres isoformas de desmocolina que se encuentran en humanos.

Proteínas adaptadoras en los desmosomas

Los dominios citoplasmáticos de las cadherinas desmosómicas se unen a la familia de proteínas del armadillo llamadas plakoglobina y placofilina, que forman una placa densa. Estas proteínas tienen las repeticiones de brazos características que funcionan como un sitio de acoplamiento para diferentes proteínas enlazadoras, como la desmoplaquina. La desmoplaquina es la proteína más abundante en un complejo desmosómico. Su carboxilo terminal contiene las repeticiones de plaquina, que se unen al filamento intermedio, formando así un vínculo entre la placa desmosómica y el citoesqueleto.

Enfermedades de la disfunción del desmosoma

La disfunción desmosómica generalmente se manifiesta como trastornos del corazón y la piel, tejidos que normalmente sufren altos niveles de tensión mecánica. Por ejemplo, las mutaciones en los genes de la desmogleína pueden causar engrosamiento epidérmico y miocardiopatía arritmogénica del ventrículo derecho (MAVD). Además, los autoanticuerpos dirigidos a las cadherinas desmosómicas causan la enfermedad autoinmune pénfigo vulgar, en la que los pacientes presentan ampollas epidérmicas debido a una débil adhesión entre células.

Desmosomas

El término desmosoma deriva de las palabras griegas "desmo" y "soma" que significan "cuerpos de adhesión". Esta estructura se observó por primera vez ...

Education

Educación

JoVE Core

Cell Biology

Biología Celular

Unit 1

Unidad 1

Cell-Cell Interactions

Interacciones célula-célula

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

desmosomes and cell anchoring

Desmosomes are cell junctions that anchor cells together. They are button-like structures that create an interlinked network of intermediate filaments across cells. This strong link helps tissues resist mechanical stress and maintain tissue integrity.

Desmosomes are built from multiple proteins. Their core includes desmosomal cadherins, which are adhesion proteins that bind to cadherins on neighboring cells. The two desmosomal cadherins are desmogleins and desmocollins. These transmembrane glycoproteins have a large extracellular region with four cadherin repeats and one anchor domain that holds them in the cell membrane.

Desmogleins and desmocollins can pair as heterodimers. They form clusters through cis-interactions on the same cell and trans-interactions between adjacent cells. In humans, there are four desmoglein isoforms and three desmocollin isoforms, and their cytoplasmic domains can differ in length because of alternative splicing.

Inside the cell, the cadherins bind armadillo family proteins called plakoglobin and plakophilin. These proteins form a dense plaque. The plaque then recruits desmoplakin, the most abundant protein in a desmosomal complex. Desmoplakin uses its carboxy-terminal plakin repeats to bind intermediate filaments, which connects the desmosome to the cytoskeleton.

Problems with desmosomes often show up in the heart and skin, where cells face high mechanical strain. Mutations in desmoglein genes can cause epidermal thickening and arrhythmogenic right ventricular cardiomyopathy, or ARVC. Autoantibodies against desmosomal cadherins can also cause pemphigus vulgaris, an autoimmune disease that leads to epidermal blisters because cell-cell adhesion becomes weak.

Desmosomes and Cell Anchoring

cell adhesion molecules - types and functions

cell-adhesion-molecules-types-and-functions

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Catenins help cells stay connected and also support signaling inside the body. These proteins act as linker proteins in cell junction complexes because they have multiple binding domains and flexible structures. Most catenins contain a protein sequence called the armadillo repeat, so they are also known as armadillo proteins. Alpha-catenin is the main exception. Catenins bind to cell adhesion molecules such as cadherins. They then connect cadherins to cytoskeletal proteins, and the exact link...

selectins

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immunoglobulin-like cell adhesion molecules

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Ig-CAMs, or immunoglobulin-like cell adhesion molecules, are cell surface glycoproteins in the immunoglobulin superfamily. They contain immunoglobulin domains, and some also have fibronectin type III domains. Their Ig domains can be glycosylated to different degrees. These molecules can bind to the same kind of Ig-CAM or to other ligands, such as integrins. Most Ig-CAMs help cells stick together only for a short time. The nectin class is different because it helps form stable junctions,...

overview of cell-cell junctions

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adherens junctions

Cell Adhesion in Tissues and Infection

Adherens junctions are strong cell-to-cell anchors that help tissues stay connected. These anchoring junctions work with desmosomes, another type of junction that holds adjacent cells together. In many epithelial and endothelial tissues, adherens junctions form a continuous adhesion belt. In heart muscle, they often appear as clusters that help cells work together for coordinated contraction. Adherens junctions are also dynamic, especially in the cells that line blood vessels. These...

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desmosomes

Desmosomes are cell junctions that anchor cells together. They are button-like structures that create an interlinked network of intermediate filaments across cells. This strong link helps tissues resist mechanical stress and maintain tissue integrity. Desmosomes are built from multiple proteins. Their core includes desmosomal cadherins, which are adhesion proteins that bind to cadherins on neighboring cells. The two desmosomal cadherins are desmogleins and desmocollins. These transmembrane...

tight junctions

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Tight junction proteins form seals between neighboring cells. These molecular barriers help stop fluids, ions, and other small solutes from leaking across body cavities and tissue compartments in multicellular organisms. They are an important part of cell barriers in places where controlled movement matters. The main tight junction proteins are claudin and occludin. Other proteins include tricellulin and JAM, which stands for junctional adhesion molecule. Most of these proteins are 4-pass...

gap junctions

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key terms and concepts

Learn how desmosomes hold cells together, link to intermediate filaments, and why defects can affect skin and heart tissue in humans.

Desmosomes and Cell Anchoring | JoVE K12

cell biology

JoVE Core Biología Celular ilustra procesos celulares complejos mediante completos vídeos animados fáciles de entender. Esta colección se centra en los componentes esenciales de las células y su funcionamiento, incluyendo los orgánulos y las membranas, el transporte celular y el metabolismo energético celular. Todo este material se complementa con los vídeos de científicos en acción, que muestran la aplicación de la biología celular en experimentos reales de investigación.

Desmosomes and Cell Anchoring

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