Triticum mosaic virus exhibits limited population variation yet shows evidence of parallel evolution after replicated serial passage in wheat

Authors

Melissa S. Bartels, University of Nebraska-LincolnFollow
Roy French, University of Nebraska-LincolnFollow
Robert A. Graybosch, USDA-ARSFollow
Satyanarayana Tatineni, USDA-ARSFollow

Document Type

Article

Date of this Version

2016

Citation

Virology 492 (2016) 92–100.

Comments

U.S. government work.

Abstract

An infectious cDNA clone of Triticum mosaic virus (TriMV) (genus Poacevirus; family Potyviridae) was used to establish three independent lineages in wheat to examine intra-host population diversity levels within protein 1 (P1) and coat protein (CP) cistrons over time. Genetic variation was assessed at passages 9, 18 and 24 by single-strand conformation polymorphism, followed by nucleotide sequencing. The founding P1 region genotype was retained at high frequencies in most lineage/passage populations, while the founding CP genotype disappeared after passage 18 in two lineages.We found that rare TriMV genotypes were present only transiently and lineages followed independent evolutionary trajectories, suggesting that genetic drift dominates TriMV evolution. These results further suggest that experimental populations of TriMV exhibit lower mutant frequencies than that of Wheat streak mosaic virus (genus Tritimovirus; family Potyviridae) in wheat. Nevertheless, there was evidence for parallel evolution at a synonymous site in the TriMV CP cistron.