The Gap Junction Communication Channel

There has been rapid progress recently in identifying and characterizing a multigene family that codes the gap junction proteins (called connexins). Two alternative nomenclature systems, one based on the molecular mass of the connexin polypeptide and the other based on evolutionary considerations (Kumar and Gilula, 1992), are currently in use. In this review, the Greek nomenclature system will be used. This review will highlight recent progress in understanding the biosynthesis, assembly, and structure of the vertebrate gap junction channel, as well as its relationship to several human diseases. Owing to a space limitation, it is not possible to provide a comprehensive review of the progress in the gap junction field. However, there are several recent reviews that can be used to obtain more information about other connexin-related topics (Musil, 1994; Leclerc, 1994; Spray, 1994; Kanno et al., 1995; Wolburg and Rohlmann, 1995).