title: Mapping viral functional domains for genetic diversity in plants.
abstract: Cucumber mosaic virus (CMV) comprises numerous isolates with various levels of in-host diversity. Subgroup-distinctive features of the Fny and LS strains provided us with a platform to genetically map the viral control elements for genetic variation in planta. We found that both RNAs 1 and 2 controlled levels of genetic diversity, and further fine mapping revealed that the control elements of mutation frequency reside within the first 596 amino acids (aa) of RNA 1. The 2a/2b overlapping region of the 2a protein also contributed to control of viral genetic variation. Furthermore, the 3' nontranslated region (NTR) of RNA 3 constituted a hot spot of polymorphism, where the majority of fixed mutations found in the population were clustered. The 2b gene of CMV, a viral suppressor of gene silencing, controls the abundance of the fixed mutants in the viral population via a host-dependent mechanism.
authors.affiliation: Department of Plant Pathology and Environmental Microbiology, and Huck Institutes of the Life Sciences, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, USA.
authors.forename: Justin S
authors.initials: JS
authors.lastname: Pita
authors.forename: Marilyn J
authors.initials: MJ
authors.lastname: Roossinck
mesh_terms: D017799:Cucumovirus / Q000235:genetics* / Q000302:isolation & purification; D014644:Genetic Variation; D059645:Mutation Rate; D010944:Plants / Q000821:virology*; D012367:RNA, Viral / Q000235:genetics*
chemical_list: D012367:RNA, Viral