Quick Reference

A hexagonal array of protein subunits, typically 10 nm in diameter and arranged as a short hollow cylinder, that penetrates the plasma membrane of certain cells and forms part of a gap junction. Connexons of closely apposed cells line up exactly to create a channel connecting the two cells, spanning the narrow gap between cells and permitting the flow of ions and small molecules between cells. In neurons and other excitable cells, connexons often occur in dense clusters and serve as low-resistance pathways along which electric current can flow between cells. The individual subunits of connexons, termed connexins, vary in molecular mass according to the type of tissue.

Subjects: Chemistry.

Reference entries