Oral Paper

         Comparative Genomics/Transcriptomics

Pleiotropy and adaptation in the silverleaf sunflower, Helianthus argophyllus

Presenting Author
UZEZI OKINEDO
Description
Pleiotropy is the control of multiple phenotypes by a single locus. According to Fisher’s model, pleiotropy is expected to slow down local adaptation unless populations are far from being optimally adapted to their environment. A recent study found that candidate locally adapted loci were enriched for high gene network connectivity, a measure of pleiotropy, in populations of common ragweed. Here we conduct comparative analyses in another member of the Asteraceae, the Texas endemic silverleaf sunflower. We used transcriptome sequences from 22 individuals in two regions (coastal and north) that represent divergent locally adapted life history strategies. We assessed genotype-expression associations, constructed gene networks, and tested for associations between genetic signatures of local adaptation and gene network connectivity. As in common ragweed, we find that silverleaf sunflower candidate loci for local adaptation are centrally located in gene network maps, substantially pleiotropic, and have higher odds of controlling the expression of other