Gap Junction Protein Gamma 1 (GJC1)

GJc1 is a member of the connexin gene family. The encoded protein is a component of gap junctions, which are composed of arrays of intercellular channels that provide a route for the diffusion of low molecular weight materials from cell to cell. The deduced 396-amino acid protein has a calculated molecular mass of about 45.5 kD. CX45 is about 97% identical to canine and mouse Cx45 and about 84% identical to chicken Cx45.

Northern blot analysis of human ventricular RNA detected a major CX45 transcript of about 2.2 kb and minor transcripts of about 5.0 and 8.0 kb. Immunohistochemical analysis of frozen left ventricle sections showed CX45 expressed with CX40 and CX43 at the intercalated disc regions, which join adjacent cardiac myocytes and contain gap junctions.