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

Desmosomes are anchoring junctions found more abundantly in tissues that experience mechanical stress, such as heart muscle and intestinal epithelium.
Cell adhesion at desmosomes is facilitated by desmosomal cadherins, namely desmocollin and desmoglein, which adhere via heterophilic interactions of their extracellular domains.
The cytoplasmic domain of the cadherins binds catenins called plakoglobins and plakophilins, which form a dense plaque on the cytoplasmic side.
The catenins cannot directly bind intermediate filaments, and are linked to them by desmoplakin- a cytoskeletal linker protein belonging to the plakin family.
Desmoplakin&#39;s N-terminal domain binds the catenins, and their C-terminal plakin repeats bind the intermediate filaments.
Thus, the desmosome anchors the intermediate filaments of adjacent cells, forming a transcellular cytoskeletal network across the tissue.

desmosomes

Desmosomes

The term desmosome derives from the Greek words &#34;desmo&#34; and &#34;soma&#34; meaning &#34;adhesion bodies.&#34; This structure was first observed during the late 1800s and described as small, dense nodules in the epidermis. Desmosomes are button-like structures that help form an interlinked network of intermediate filaments across the cells. These junctions are&#160; essential to hold cells together under mechanical stress and to maintain tissue integrity. Desmosomes are multi-protein complexes comprising desmosomal cadherins that are linked to intermediate filaments via various adapter proteins.
Desmosomal Cadherins
The cadherins form the extracellular core region of a desmosome and bind cadherins on the adjacent cell. There are two types of cadherins in desmosomes &#8212; desmogleins and desmocollins. These transmembrane glycoproteins possess a large extracellular portion comprising four cadherin repeats and one extracellular anchor domain that anchors these proteins to the cell membrane. Heterodimeric pairs of desmogleins and desmocollins form clusters by cis-interactions on the same cell and trans-interactions between adjacent cells. Their cytoplasmic domains can vary in length between the different isoforms due to alternative splicing &#8212; for example, there are four desmoglein isoforms and three desmocollin isoforms found in humans.
Adapter Proteins in Desmosomes
The cytoplasmic domains of desmosomal cadherins bind the armadillo family of proteins called plakoglobin and plakophilin, which form a dense plaque. These proteins have the characteristic arm repeats that function as a docking site for different linker proteins, such as desmoplakin. Desmoplakin is the most abundant protein in a desmosomal complex. Their carboxy-terminal contains the plakin repeats, which bind the intermediate filament, thus forming a link between the desmosomal plaque and the cytoskeleton.
Diseases of Desmosome Dysfunction
Desmosomal dysfunction usually manifests as disorders of the heart and skin &#8212; tissues typically undergoing high levels of mechanical strain. For example, mutations in the desmoglein genes can cause epidermal thickening and arrhythmogenic right ventricular cardiomyopathy (ARVC). Additionally, autoantibodies targeting the desmosomal cadherins cause the autoimmune disease&#160; pemphigus vulgaris, in which patients exhibit epidermal blisters due to weak cell-cell adhesion.

The term desmosome derives from the Greek words &#34;desmo&#34; and &#34;soma&#34; meaning &#34;adhesion bodies.&#34; This structure was first observed ...

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JoVE Core

Cell Biology

Unit 1

Cell-Cell Interactions

KEY TERMS AND CONCEPTS

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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Cadherins are cell adhesion proteins that help cells stick together and build tissues. Their name comes from their calcium-dependent binding. Early examples were named E-cadherin, P-cadherin, and N-cadherin after the epithelial, placental, and neuronal cells where they were first found. Classical cadherins share similar sequences and structures. Other cadherins, including those involved in cell signaling, are grouped as non-classical cadherins. This diversity comes from multiple cadherin genes...

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catenins

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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

immunoglobulin-like-cell-adhesion-molecules

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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...

tension response at adherens junctions

How Adherens Junctions Sense Force

Adherens junctions help cells stay attached while they respond to mechanical force. These multi-protein complexes can adapt to tensile force and shear stress. When the force changes, mechanosensory proteins in the junction can change shape. This process is called mechanotransduction. Alpha-catenin is one of the main force-sensing proteins in adherens junctions. It is an allosteric protein, which means its shape affects how it works. Alpha-catenin has three VH, or vinculin homology, domains...

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 Cell Biology illustrates complex cellular processes in easy-to-understand yet comprehensive animated video lessons. This collection focuses on the essential components and functions of cells, including organelles and membranes, cellular transport, and cell energetics. It is complemented by scientist-in-action videos that demonstrate the application of cell biology in real-world research experiments.

Desmosomes and Cell Anchoring

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