MEDICAL PHYSIOLOGY

Detailed explanation-1: -Connexins are the proteins that form the intercellular channels of gap junctions. An individual channel is created by two hemichannels (connexons), each located in the plasma membrane of adjacent cells and composed of six integral membrane protein subunits (connexins).

Detailed explanation-2: -Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins.

Detailed explanation-3: -Gap junctions are clusters of intercellular channels that allow direct diffusion of ions and small molecules between adjacent cells. The intercellular channels are formed by head-to-head docking of hexameric assemblies (connexons) of tetraspan integral membrane proteins, the connexins (Cx) (Goodenough et al. 1996).

Detailed explanation-4: -Gap junctions connect cells via channels not open to the extracellular space and permit the passage of ions and molecules of  1 kDa. Single connexin hemichannels, which are connexin hexamers, are present in the surface membrane before docking with a hemichannel in an apposed membrane.