Connexin gap junction channel (Connexin (Cx))

Connexin gap junction channels are formed by the docking of two hemichannels (connexons), each composed of six connexin proteins, between neighboring cells, creating a direct cytoplasmic connection that allows ions and small metabolites (up to ~1 kDa) to pass between cells, facilitating electrical and metabolic coupling[4][5][7]. There are at least 21 connexin isoforms in humans, with connexin43 (Cx43), connexin26 (Cx26), and connexin32 (Cx32) being some of the best studied[4][5][2]. Gap junction channels are crucial for synchronized cell function in the heart, brain, liver, and other tissues[4][5]. Individual connexin channels display unique permeability, gating, and selectivity properties[5]. They are regulated by voltage, pH, calcium ions, phosphorylation, and various metabolites[3][1]. Mutations or dysregulation of connexins are linked to diverse diseases, including arrhythmias, cancer, deafness, and skin disorders[2][4]. Drugs may block or modulate connexin channels, but clinical use is limited due to challenges in isoform specificity and broad tissue distribution[4].

Other names

Gap junction channelConnexin channelGap junction proteinGap junctionCx channel

Channel blockage (inhibition of ion and molecule passage through the channel) Modulation of channel gating Alteration of phosphorylation or degradation Disruption of intercellular coupling