Recombinants of Potato Virus Y- Origin and Evolution

Kelsie Evans, Bioinformatics and Computational Biology

3rd Place: Graduate Interdisciplinary Research Presentation

Abstract: Potato virus Y (PVY) exists as a complex of strains, including a growing number of recombinants. Evolution of PVY proceeds through accumulation of mutations and more rapidly through recombination, combining large sections of parental genomes, which leads to adaptation of the virus to multiple potato cultivars and a wider range of environmental conditions. The role of recombination in PVY evolution and origin of the common PVY recombinants, such as PVYN:O, PVYN-Wi, and PVYNTN, were studied here through whole genome sequencing of PVY genomes and subsequent recombination and phylogenetic analysis. A collection of 119 newly sequenced PVY isolates and 166 PVY genomes from the GenBank database was subjected to phylogenetic analysis, focusing on large genome sections commonly involved in recombination. Two new PVYC recombinants were sequenced and identified. A substantial diversity was revealed within non-recombinant parental strain types PVYO and PVYN, with several distinct lineages identified. This diversity in the parental sequences allowed us to trace the origins and evolution of all recombinant types of PVY, which also showed considerable diversity in most cases. From the clade placement for different genome sections, it was elucidated that certain recombinant types are formed from different parental sequences and hence likely to have some selective advantages.