Colloquium in Plant Genetics and Breeding: Polyploidy


Seminar Announcement

Department of Plant Agriculture
Colloquium in Plant Genetics and Breeding: Polyploidy

Date: Friday 13 March 2020
Time: 3pm
Location: CRSC 121B

Title: Homeolog Expression Bias and its Implications for Crop Adaptation

Name: Cory Schilling


Polyploidy is an important evolutionary process that plays a significant role in generating genetic diversity. After polyploidization, polyploids must reconcile the doubling of chromosome pairs to ensure proper function of regulatory machinery. How this reconciliation occurs is still not well understood, but studies of homeolog expression bias (HEB) may help us better understand the relationship between polyploidization and the divergence of gene function. This seminar will provide an overview of the underlying principles of polyploidy and HEB in plants, followed by a review of some key studies illustrating how HEB impacts gene expression. An investigation of the theorized mechanistic causes of HEB will also be presented. Lastly, potential implications of HEB for crop adaptation to climate change will be discussed.


Akhunova, AR., Matniyavoz, RT., Liang, H., Akhunov, ED. 2010. Homeolog-specific transcriptional bias in allopolyploid wheat. BMC Genomics. 11: 505.
Bardil, A., de Almeida, JD., Combes, MC., Lashermes, P., Bertrand, B. 2011. Genomic expression dominance in the natural allopolyploid Coffea arabica is massively affected by growth temperature. New Phytologist. 192: 760-774.
Chaudhary, B., Flagel, L., Stupar, RM., Udall, JS., Verma, N., Springer, NM., Wendel, JF. 2009. Reciprocal silencing, transcriptional bias and functional divergence of homeologs in polyploid cotton (Gossypium). Genetics Society of America. 182: 503-517.
Chen, ZJ. Genetic and epigenetic mechanisms for gene expression and phenotypic variation in plant polyploids. 2007. Annual Review of Plant Biology. 58: 377-406.
Flagel, LE, Wendel, JF. 2009. Evolutionary rate variation, genomic dominance and duplicate gene expression evolution during allotetraploid cotton speciation. New Phytologist. 186:184-193.
Grover, C.E., Gallagher, JP., Szadkowski, EP., Yoo, MJ., Flagel, LE., Wendel, JF. 2012. Homoelog expression bias and expression level dominance in allopolyploids. New Phytologist. 196:966-971.
Hughes, TE., Langdale, JA., Kelly, S. 2014. The impact of widespread regulatory neofunctionalization on homeolog gene evolution following whole-genome duplication in maize. Genome Research. 24: 1348-1355.
Rapp, RA., Udall, JA., Wendel, JF. 2009. Genomic expression dominance in allopolyploids. BMC   Biology. 7:18.
Smith, RD., Kinser, TK., Conradi Smith, GD., Puzey, JR. 2019. A likelihood ratio test for changes in homeolog expression bias. BMC Bioinformatics. 20:149.
Yoo, M-J., Szadkowski, E., Wendel, JF. 2013. Homeolog expression bias and expression level dominance in allopolyploid cotton. Heredity. 110:171-180.