Abstract Detail

Comparative Genomics/Transcriptomics

McKibben, Michael [1], Barker, Michael [1].

Candidate Domestication Genes in Multiple Crops are Enriched With Paleologs from Ancient Whole Genome Duplications.

Current estimates show up to 35% of extant flowering plant species are polyploids, and all have experienced at least one whole genome duplication event (WGD) in their evolutionary history. Despite this ubiquity, relatively little is known about the long term genetic impact of these WGDs on the diploidized descendents. Recent phylogenetic analyses have found that polyploidy is a key trait associated with crop domestication, but the genetic diversity of WGDs has yet to be directly connected to crop domestication. Here we explore the impacts WGD has on genes under selection during the domestication of 23 crop species from a variety of lineages. Using evidence from synteny and synonymous divergence (Ks) values associated with ancient WGDs, we identified paleologs that originated from ancient WGD in each crop’s genome. Candidate genes associated with domestication were retrieved from the literature and analyzed for evidence of paleolog enrichment. For 9 of the 23 taxa, candidate genes were significantly enriched with paleologs from at least one WGD event. We observed that the amount of genome fractionation was significantly associated with whether the candidate genes from a crop were enriched with paleologs. Crops with younger, less fractionated WGDs were more likely to have paleologs over-represented among their candidate genes. These results suggest that ancient WGDs continue to impact plant domestication and potential adaptation millions of years later.

1 - University of Arizona, Department Of Ecology & Evolutionary Biology,, P.O. Box 210088, Tucson, AZ, 85721, United States

Keywords:
polyploidy
Crops
domestication
Whole-genome duplication
Paleologs
evolution
comparative genomics
PGLS.

Presentation Type: Oral Paper
Session: CG2, Functional & Comparative Genetics/Genomics II
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 4:00 PM
Number: CG2005
Abstract ID:472
Candidate for Awards:None