Desmosomes: just cell adhesion or is there more?

Desmosomes are specialized junctions that play a role in cell adhesion. These structures are especially prevalent in cells from ectodermal lineages. Their importance is evident in tissues exposed to mechanical stress, such as the skin and heart. Prior research has shown that disruptions in desmosomal genes can lead to tissue fragility in mice. Human patients with impaired desmosome function often suffer from severe skin disorders or fatal heart conditions. While desmosomes are known for their structural role, recent findings suggest additional functions. This gap motivated investigations into whether desmosomes might also serve signaling roles. Understanding these roles could expand the known functions of desmosomes beyond mere adhesion.

This review explores whether desmosomes have roles beyond cell adhesion. The specific problem is understanding if these junctions can transmit signals from the extracellular environment to the nucleus. The motivation comes from observations that desmosomal proteins may influence transcriptional processes. The study aims to synthesize evidence on signaling properties of desmosomes. It focuses on how these junctions might affect developmental processes. The authors propose that desmosomes could regulate transcriptional co-factors. This paper seeks to clarify the signaling potential of desmosomes. The goal is to highlight how these structures might contribute to disease mechanisms.

The authors conducted a literature review to evaluate the role of desmosomes in signaling. They analyzed studies on desmosomal proteins and their interactions with transcriptional co-factors. Data sources included mouse models with desmosomal gene mutations. The review also incorporated clinical observations of patients with desmosomal disorders. The study examined how desmosomal proteins like plakoglobin and plakophilins function. The approach included assessing evidence for signaling pathways involving these proteins. The authors compared findings from developmental biology and disease models. They synthesized results to propose new roles for desmosomes.

The strongest finding is that desmosomes may transmit signals from the extracellular environment to the nucleus. Evidence suggests that desmosomal proteins can regulate transcriptional co-factors. Plakoglobin and plakophilins are part of the armadillo family of proteins. These proteins may influence gene expression by controlling cytoplasmic pools. The review highlights that desmosomal signaling could affect developmental processes. Skin and skin appendage development may be influenced by desmosomal signaling. Abnormal signaling through desmosomes may contribute to disease symptoms. The findings suggest that desmosomes have roles beyond structural adhesion.

The authors conclude that desmosomes are more than structural adhesion structures. They propose that these junctions may transmit signals to the nucleus. The evidence suggests that desmosomal proteins can regulate transcriptional co-factors. This signaling may influence developmental processes like skin formation. Abnormal signaling through desmosomes may contribute to disease mechanisms. The study highlights the need for further research on desmosomal signaling. The authors suggest that understanding these roles could provide new insights. The findings imply that desmosomes have broader biological functions.