Molecular cloning of a cDNA encoding the amphibian Pleurodeles waltl 70-kDa heat-shock cognate protein.

We isolated and characterized a cDNA coding for heat-shock protein 70 of the amphibian Pleurodeles waltl. This 2212-bp sequence exhibited one open reading frame of 645 amino acids. The predicted amino acid sequence exhibited the three conserved elements of the HSC/HSP70 protein family. Comparison of nucleotide and amino acid sequences between this gene and other hsc/hsp-like genes revealed a high identity with the cognate form HSC70. By in vitro translation, this gene encoded a 70-kDa protein which was different than the inducible Pleurodeles waltl HSP70 protein. This translated protein was recognized by Pleurodeles waltl N1 anti-HSC/HSP70 antibody. Heat-inducibility tests showed that this gene was constitutively expressed during oogenesis and embryogenesis, and its expression was not increased after a heat-shock. These results led us to conclude that we recovered a Pleurodeles waltl cognate hsc70 gene.