title: Mutational bias of Turnip Yellow Mosaic Virus in the context of host anti-viral gene silencing.
abstract: Plant Dicer-like (DCL) enzymes exhibit a GC-preference during anti-viral post-transcriptional gene silencing (PTGS), delivering an evolutionary selection pressure resulting in plant viruses with GC-poor genomes. However, some viruses, e.g. Turnip Yellow Mosaic Virus (TYMV, genus Tymovirus) have GC-rich genomes, raising the question as to whether or not DCL derived selection pressure affects these viruses. In this study we analyzed the virus-derived small interfering RNAs from TYMV-infected leaves of Brassica juncea showed that the TYMV population accumulated a mutational bias with AU replacing GC (GC-AU), demonstrating PTGS pressure. Interestingly, at the highly polymorphic sites the GC-AU bias was no longer observed. This suggests the presence of an unknown mechanism preventing mutational drift of the viral population and maintaining viral genome stability, despite the host PTGS pressure.
authors.affiliation: BGI-shenzhen, Beishan Road, Yantian, Shenzhen 518083, China.
authors.forename: Jinmin
authors.initials: J
authors.lastname: Ma
authors.affiliation: NERC/Centre for Ecology & Hydrology, Benson Lane, Wallingford, Oxfordshire OX10 8BB, UK.
authors.forename: Denise
authors.initials: D
authors.lastname: Pallett
authors.affiliation: BGI-shenzhen, Beishan Road, Yantian, Shenzhen 518083, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.affiliation: BGI-shenzhen, Beishan Road, Yantian, Shenzhen 518083, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Hou
authors.affiliation: BGI-shenzhen, Beishan Road, Yantian, Shenzhen 518083, China; NERC/Centre for Ecology & Hydrology, Benson Lane, Wallingford, Oxfordshire OX10 8BB, UK; Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK. Electronic address: huw@ceh.ac.uk.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
mesh_terms: D020868:Gene Silencing; D016679:Genome, Viral; D054884:Host-Pathogen Interactions; D009149:Mustard Plant / Q000235:genetics / Q000821:virology*; D009154:Mutation; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology; D034741:RNA, Small Interfering / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D017806:Tymovirus / Q000235:genetics* / Q000502:physiology
chemical_list: D034741:RNA, Small Interfering; D012367:RNA, Viral
keywords: Anti-viral post-transcriptional gene silencing; Brassica juncea; Mutational bias; Turnip Yellow Mosaic Virus; Virus population