Desmosomer

Desmosomer, more commonly called desmosome in English, is a multiprotein cell–cell junction that provides strong adhesion between adjacent cells. Desmosomes link the intermediate filament networks of neighboring cells, reinforcing tissues that experience significant mechanical stress, such as the epidermis and cardiac muscle.

Composition: The extracellular regions of transmembrane cadherins—desmogleins and desmocollins—mediate Ca2+-dependent adhesion between neighboring cells. The cytoplasmic plaque comprises desmoplakin, plakophilins, and plakoglobin (gamma-catenin), which couple the cadherins to keratin intermediate filaments. Through this arrangement, desmosomes distribute tensile forces and contribute to tissue integrity. Desmosomes are dynamic structures that assemble at cell–cell interfaces during development and wound healing and can be remodeled in response to mechanical cues.

Clinical relevance: Autoimmune pemphigus vulgaris targets desmoglein 1 and 3, leading to loss of cell adhesion and blistering. Mutations in desmosomal components (for example, desmoplakin, plakophilin, plakoglobin) are linked to hereditary cardiomyopathies such as arrhythmogenic right ventricular cardiomyopathy and to skin–cardiac syndromes including Carvajal and Naxos. Alterations in desmosomal signaling and adhesion have also been studied in cancer progression.