Desmocollins

Desmocollins are a family of desmosomal cadherins that mediate cell–cell adhesion within desmosomes, specialized junctions that confer mechanical strength to tissues. In humans, three desmocollin genes encode Desmocollin-1 (DSC1), Desmocollin-2 (DSC2), and Desmocollin-3 (DSC3). These proteins are single-pass transmembrane glycoproteins characterized by extracellular cadherin (EC) repeats that mediate calcium-dependent adhesion.

Desmocollins interact with desmosomal plaque proteins through their cytoplasmic tails, linking to intermediate filaments via desmoplakin and plakophilins and plakoglobin (gamma-catenin). This cytoplasmic complex supports desmosome assembly and stability, enabling intercellular cohesion under mechanical stress. Desmocollins can participate in homophilic interactions with identical desmocollin molecules on adjacent cells and in heterophilic interactions with desmogleins or other desmosomal cadherins, contributing to the adhesive core of desmosomes.

Expression patterns vary among tissues. DSC1 is predominantly expressed in stratified squamous epithelia such as skin and oral mucosa, while DSC2 and DSC3 have broader distribution and are found in epithelia and, in some contexts, cardiac tissue where desmosomes are critical for structural integrity.

Clinical relevance: Alterations in desmocollin expression or function have been linked to human disease. Mutations in DSC2 are associated with cardiomyopathies, including arrhythmogenic forms, and changes in desmocollin expression have been reported in skin disorders and some cancers. Research continues to define the precise roles of DSC1–DSC3 in development and disease.