Evolution of genes involved in regulating flowering time in grasses

The VRN2 gene is a conserved repressor of flowering in grasses.

The Science

Studies of gene knockdown and overexpression experiments test whether the circuitry of the genes regulating the initiation of flowering is conserved across various grass species.   

The Impact

Increasing biomass yield could improve the economics of biomass as an energy source. Furthering the molecular-level understanding of the flowering regulatory network in the model grass Brachypodium could allow for manipulation of flowering time, a trait affecting biomass yield.

Summary

The flowering of many plant species is coordinated with seasonal environmental cues such as temperature and photoperiod. In winter wheat and barley, three genes – VRN1, VRN2, and FT – form a regulatory loop that regulates the initiation of flowering. Here, we test whether the circuitry of this regulatory loop is conserved across Pooid grasses. Our studies reveal that some aspects of the regulatory loop, such as the cold repression of VRN2, are unique to wheat and barley. However, this study, as well some of our previous work, demonstrates that VRN2 is a repressor of flowering that functions broadly in grasses from rice to Brachypodium, and thus VRN2 is a target for fine tuning of flowering in grass biofuel crops. 

Contacts (BER PM)

N. Kent Peters
Program Manager, Office of Biological and Environmental Research
kent.peters@science.doe.gov, 301-903-5549

(PI Contact)

Richard M. Amasino
University of Wisconsin - Madison
amasino@biochem.wisc.edu

Funding
This work was funded by the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science DE-FC02-07ER64494), USDA-HATCH, the National Science Foundation (IOS-1353056 and Grant IOS-1258126), a National Institutes of Health-sponsored pre-doctoral training fellowship to the University of Wisconsin Genetics Training Program, and the China Scholarship Council. 

Publications

Woods, D.P. et al. “Evolution of VRN2/Ghd7-like genes in vernalization-mediated repression of grass flowering.” Plant Physiology 170, 2124-2135 (2016) [DOI: 10.1104/pp.15.01279].

Related Links

http://www.plantphysiol.org/content/170/4/2124.long

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