Genome hyperevolution and the success of a parasite

Barry, J.D., Hall, J.P.J. and Plenderleith, L. (2012) Genome hyperevolution and the success of a parasite. Annals of the New York Academy of Sciences, 1267(1), pp. 11-17. (doi: 10.1111/j.1749-6632.2012.06654.x)

Abstract

The strategy of antigenic variation is to present a constantly changing population phenotype that enhances parasite transmission, through evasion of immunity arising within, or existing between, host animals. Trypanosome antigenic variation occurs through spontaneous switching among members of a silent archive of many hundreds of variant surface glycoprotein (VSG) antigen genes. As with such contingency systems in other pathogens, switching appears to be triggered through inherently unstable DNA sequences. The archive occupies subtelomeres, a genome partition that promotes hypermutagenesis and, through telomere position effects, singular expression of VSG. Trypanosome antigenic variation is augmented greatly by the formation of mosaic genes from segments of pseudo-VSG, an example of implicit genetic information. Hypermutation occurs apparently evenly across the whole archive, without direct selection on individual VSG, demonstrating second-order selection of the underlying mechanisms. Coordination of antigenic variation, and thereby transmission, occurs through networking of trypanosome traits expressed at different scales from molecules to host populations.

• Item Type: Articles
• Additional Information: The definitive version is available at www.blackwell-synergy.com and on a mirror site hosted by HighWire at www.annalsnyas.org
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Barry, Professor J
• Authors: Barry, J.D., Hall, J.P.J., and Plenderleith, L.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Annals of the New York Academy of Sciences
• Publisher: Wiley-Blackwell Publishing, Inc. on behalf of New York Academy of Sciences
• ISSN: 0077-8923
• Published Online: 06 September 2012
• Copyright Holders: Copyright © 2012 New York Academy of Sciences
• First Published: First published in Annals of the New York Academy of Sciences 1267(1):11-17
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher