Publication Abstract from PubMed
HERV-FRD is a human endogenous retrovirus that entered the human genome 40 million years ago. Its envelope gene, syncytin-2, was diverted by an ancestral host most probably because of its fusogenic property, for a role in placenta morphogenesis. It was maintained in a functional state in all primate branches as a bona fide cellular gene, submitted to a very low mutation rate as compared to infectious retrovirus genomes. The structure of the syncytin-2 protein thus provides a good insight into that of the oldest mammalian retroviral envelope. Here, we report the crystal structure of a central fragment of its "fossil" ectodomain, allowing a remarkable superposition with the structures of the corresponding domains of present-day infectious retroviruses, in spite of a more than 60% divergent sequence. These results suggest the existence of a unique structural solution selected by these proteins for their fusogenic function.
Crystal structure of a pivotal domain of human syncytin-2, a 40 million years old endogenous retrovirus fusogenic envelope gene captured by primates.,Renard M, Varela PF, Letzelter C, Duquerroy S, Rey FA, Heidmann T J Mol Biol. 2005 Oct 7;352(5):1029-34. PMID:16140326[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.