Desmocollines

Desmocollines are a family of transmembrane proteins that play a crucial role in cell adhesion, specifically within desmosomes. Desmosomes are specialized adhesive structures that link cells together, providing mechanical strength and stability to tissues, particularly in epithelial and cardiac muscle. Desmocollines, along with desmogleins, are the cadherin superfamily members that form the extracellular adhesion molecules of desmosomes.

There are three known types of desmocollines: desmocolline-1, desmocolline-2, and desmocolline-3. These proteins have a characteristic structure, featuring an extracellular domain, a transmembrane domain, and a cytoplasmic tail. The extracellular domains interact with those of desmocollines on adjacent cells, mediating homophilic or heterophilic binding. The cytoplasmic tails anchor the desmosome to the cell's cytoskeleton, primarily intermediate filaments, through a complex of adapter proteins.

Desmocollines are expressed in a tissue-specific manner and their precise roles are still under investigation. However, their presence is essential for the proper formation and function of desmosomes. Mutations in genes encoding desmocollines have been linked to various human diseases, including certain forms of arrhythmogenic right ventricular cardiomyopathy (ARVC) and arrhythmogenic cardiomyopathy (ACM), highlighting their importance in maintaining tissue integrity and function. Research continues to explore the molecular mechanisms by which desmocollines contribute to cell adhesion and tissue development.