Innexin

An innexin is a member of a class of proteins which is used to create gap junctions in invertebrates. The innexin protein and its vertebrate homologue pannexin1 have four transmembrane spanning units and, like the vertebrate connexin gap junction protein, six innexin (or pannexin 1) subunits together form a channel, an "innexon", in the plasma membrane between the inside and outside of the cell. Two innexons in apposed plasma membranes can form a gap junction.