Gap junction alpha-1 protein (Connexin 43) (Cx43)

Gap junction alpha-1 protein, widely known as Connexin 43 (Cx43), is a critical transmembrane protein that facilitates direct intercellular communication by forming gap junction channels and hemichannels. In the heart, Cx43 is the primary protein responsible for electrical coupling between cardiomyocytes, ensuring synchronized contraction and a stable heart rhythm (UniProt P17302). Beyond the cardiovascular system, it is abundantly expressed in astrocytes, fibroblasts, and keratinocytes, where it regulates metabolic exchange and coordinates tissue responses to injury (PMID: 30111316). Dysfunctional Cx43 signaling is a hallmark of several pathologies, including cardiac arrhythmias, chronic inflammatory diseases, and impaired wound healing (PMID: 28213357). In oncology, Cx43 exhibits a complex role, often acting as a tumor suppressor in early stages but potentially facilitating metastasis in later stages (PMID: 31430494). Therapeutic interventions targeting Cx43 include mimetic peptides like αCT1 and small molecules like danegaptide, which aim to either enhance gap junctional coupling or selectively inhibit hemichannel-mediated inflammatory release (PMID: 29348638). These strategies are currently being explored for treating myocardial infarction, stroke, and chronic skin ulcers.

Other names

GJA1Connexin-43Gap junction 43 kDa heart proteinODDDAVSD3HLHS1

Gap junction modulation (opening or blocking) and selective hemichannel inhibition