Desmosome assembly, homeostasis, and desmosomal disease

Abstract

Cell–cell adhesion is involved in all aspects of tissue behavior in multicellular organisms, from tissue morphogenesis (regulation of cell shape, apoptosis, cell movement, and development of complex structures) to aging and disease. A major player in the dynamic regulation of intercellular contacts is the desmosome. Knowledge of the desmosome has evolved over 150 years from the notion of a static, punctuate, adhesive barrier structure to one of the finely tuned multifunctional complexes involved in the regulation of numerous and diverse aspects of keratinocyte physiology and disease. In this context, nondesmosomal regulatory molecules have been acquiring increasing importance in the study of desmosome homeostasis and have become part of the extended desmosomal interactome named “desmo-adhesome”. Among these associated molecules, kinases are the prominent regulators of both desmosome remodeling and acquisition of hyperadhesion, two novel concepts in cell–cell adhesion. Spatiotemporal changes in the expression and regulation of desmosomal proteins also underlie a number of genetic, infectious, autoimmune, and malignant conditions. In addition to offering a systems-level view of the molecular composition of desmosomes, we also discuss the mechanisms that regulate, and disrupt, desmosome homeostasis.