The evolutionary interplay between exogenous and endogenous sheep betaretroviruses

Armezzani, A., Murphy, L., Spencer, T. E., Palmarini, M. and Arnaud, F. (2012) The evolutionary interplay between exogenous and endogenous sheep betaretroviruses. In: Witzany, G. (ed.) Viruses: Essential Agents of Life. Springer Netherlands: Dordrecht, pp. 293-307. ISBN 9789400748989 (doi: 10.1007/978-94-007-4899-6_15)

Abstract

Sheep betaretroviruses represent an interesting model to study the ­complex evolutionary interplay between host and pathogen in natural settings. In infected sheep, the exogenous and pathogenic Jaagsiekte sheep retrovirus (JSRV) coexists with at least 27 highly related endogenous JSRVs (enJSRVs). During evolution, some enJSRVs were co-opted by the host as they fulfilled important biological functions, including protection against infections by related exogenous retroviruses as well as conceptus development and placental morphogenesis. In particular, recent studies demonstrate that transdominant enJSRVs (i.e., those that are able to block JSRV replication) were positively selected during sheep domestication. Interestingly, viruses escaping these loci have recently emerged (less than 200 years ago). Overall, these findings suggest that the process of endogenization is still ongoing in sheep and, therefore, the evolutionary interplay between endogenous and exogenous sheep betaretroviruses and their hosts has not reached equilibrium.

• Item Type: Book Sections
• Status: Published
• Glasgow Author(s) Enlighten ID: Palmarini, Professor Massimo
• Authors: Armezzani, A., Murphy, L., Spencer, T. E., Palmarini, M., and Arnaud, F.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Centre for Virus Research
• Publisher: Springer Netherlands
• ISBN: 9789400748989