Natural variation in timing of stress-responsive gene expression predicts heterosis in intraspecific hybrids of Arabidopsis

Citations Over TimeTop 10% of 2015 papers

Abstract

The genetic distance between hybridizing parents affects heterosis; however, the mechanisms for this remain unclear. Here we report that this genetic distance correlates with natural variation and epigenetic regulation of circadian clock-mediated stress responses. In intraspecific hybrids of Arabidopsis thaliana, genome-wide expression of many biotic and abiotic stress-responsive genes is diurnally repressed and this correlates with biomass heterosis and biomass quantitative trait loci. Expression differences of selected stress-responsive genes among diverse ecotypes are predictive of heterosis in their hybrids. Stress-responsive genes are repressed in the hybrids under normal conditions but are induced to mid-parent or higher levels under stress at certain times of the day, potentially balancing the tradeoff between stress responses and growth. Consistent with this hypothesis, repression of two candidate stress-responsive genes increases growth vigour. Our findings may therefore provide new criteria for effectively selecting parents to produce high- or low-yield hybrids.

Related Papers

• The Relationship among Yield Structure Heterosis of Strong Heterosis Hybrid Wheat(2002)
• Dissecting heterosis architecture in lentil(2001)
• Study on Tolerance and Enrichment Characteristics of Sedum alfredii Hance to Cd in Soil Culture(2011)
• Comparison of glucosinolates in two Thellungiela salsuginea ecotypes(2014)
• Analysis of Heterosis of Yield and Fiber Quality Traits for Genetic Male Hybrid in Cotton(2010)