Origin of secretin receptor precedes the advent of tetrapoda: evidence on the separated origins of secretin and orexin.

ABSTRACT: At present, secretin and its receptor have only been identified in mammals, and the origin of this ligand-receptor pair in early vertebrates is unclear. In addition, the elusive similarities of secretin and orexin in terms of both structures and functions suggest a common ancestral origin early in the vertebrate lineage. In this article, with the cloning and functional characterization of secretin receptors from lungfish and X. laevis as well as frog (X. laevis and Rana rugulosa) secretins, we provide evidence that the secretin ligand-receptor pair has already diverged and become highly specific by the emergence of tetrapods. The secretin receptor-like sequence cloned from lungfish indicates that the secretin receptor was descended from a VPAC-like receptor prior the advent of sarcopterygi

SUBMITTER: Tam JK 

PROVIDER: S-EPMC3084839 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature