Cloning and characterization of human and rat liver cDNAs coding for a gap junction protein.

TLDR

The cDNA is 1,574 bases long and encodes the full coding region of a gap junction protein. An extended 58‑mer oligonucleotide was used to identify a human liver gap junction cDNA, which was then used to screen a rat liver cDNA library, yielding a rat liver junction cDNA clone. In vitro translation shows the cDNA encodes a 32,022‑Da protein, Southern blotting confirms it is a single‑copy gene detectable across species, and the rat liver clone is 1,127 bases long with strong coding‑region homology to the human sequence but less 3′‑UTR similarity.

Abstract

An extended synthetic oligonucleotide (58-mer) has been used to identify and characterize a human liver gap junction cDNA. The cDNA is 1,574 bases long and contains the entire coding region for a gap junction protein. In vitro translation of the RNA products of this cDNA is consistent with it coding for a 32,022-D protein. Southern blot analysis indicates that the gap junction gene is present as a single copy, and that it can be detected in a variety of organisms using the human liver cDNA as a probe. The human cDNA has been used to screen a rat liver cDNA library, and a rat liver junction cDNA clone has been isolated. The rat liver clone is 1,127 bases in length, and it has strong sequence homology to the human cDNA in the protein-coding region, but less extensive homology in the 3'-untranslated region.