Abstract Detail

Genomics / Proteomics

Sessa, Emily [1], Barker, Michael [2].

Absolute dosage and functional diversification drive majority of gene retention following polyploidy in the Compositae.

Whole-genome duplication (WGD) is now recognized as a ubiquitous phenomenon in plant evolution, with most major lineages of angiosperms having experienced at least one of these events, or paleopolyploidies, in their history. In most gene pairs duplicated via paleopolyploidy (paleologs), one member is lost relatively quickly, but some pairs of paleologs are maintained over time, and these make up a significant portion of many modern plant genomes. These retained genes are often biased with respect to Gene Ontology (GO) functional category, and several models have been suggested to account for these biased retention patterns, particularly the dosage or gene balance hypothesis (DBH). Most predictions for specific functional categories expected to be over-retained in plants due to DBH following WGD come from studies of Arabidopsis thaliana, but in several cases, including the Compositae (sunflower family), patterns of biased retention following WGD are not consistent with those seen in Arabidopsis. We developed a four-part test using retention patterns and molecular sequence criteria that dosage-sensitive loci should meet, in order to determine whether paleolog retention is consistent with DBH as opposed to some other process, such as absolute dosage or neo/subfunctionalization. We find that across Compositae, more retention is consistent with the latter two processes than with DBH.

Broader Impacts:

1 - University of Arizona, Ecology & Evolutionary Biology, 1041 E Lowell Street, Tucson, AZ, 85721, USA
2 - University of Arizona, Ecology & Evolutionary Biology, P.O. Box 210088, Tucson, AZ, 85712, USA

Keywords:
Asteraceae
dosage balance hypothesis
neofunctionalization
subfunctionalization
absolute dosage
paleopolyploidy
functional divergence of gene duplicates
gene ontology (GO).

Presentation Type: Oral Paper:Papers for Topics
Session: 24
Location: Newberry/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 10:00 AM
Number: 24001
Abstract ID:665
Candidate for Awards:None