Tags: Protein.
An innexin is a member of a family of proteins that create gap junctions in invertebrates. The innexin proteins have four transmembrane spanning units and like the vertebrate connexin gap junction protein six innexin 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. Innexin genes have homologues in vertebrates called pannexins.