Special transmembrane proteins which make up gap junctions is called as: (A) Cadherins, (B) Occludins, (C) Connexons, (D) Claudins
Answer is C. Communicating junctions (gap junctions) mediate the passage of chemical or electrical signals from one cell to another. The junction consists of a dense planar array of 1.5- to 2-nm pores (called connexons) formed by hexamers of transmembrane proteins called connexins. These pores permit the passage of ions, nucleotides, sugars, amino acids, vitamins, and other small molecules; the permeability of the junction is rapidly reduced by lowered intracellular pH or increased intracellular calcium. Gap junctions play a critical role in cell-cell communication.Ref: Robbin&;s; 9th edition; Chapter 1; The Cell as a Unit of Health and Disease