Unraveling the molecular mechanisms underlying high ambient temperature acclimation in plants using the novel growth regulator Heatin.

Abstract

High ambient temperature is most detrimental to plants and crop yield. Food security is therefore threatened in the current era of global warming and an increasing world population. Plants respond to high ambient temperatures by several architectural adaptations, collectively called the High Temperature Acclimation Response (HTAR). Despite the important societal and economic impact of these adaptations, the molecular mechanisms underlying HTAR and thermosensing are hardly understood. I have identified a novel growth regulator that enhances HTAR using a chemical genetics screen. This novel growth regulator, named Heatin, does not affect plant growth under control temperatures. In this project, I propose to use Heatin to understand the mechanisms underlying HTAR. I propose to identify the plant protein targets of Heatin and to uncover genetic networks targeted by Heatin. A transcriptome analysis will reveal genes regulated by Heatin. In addition, a genome-wide association study that links genomic loci to the Heatin response will be performed. This information will be combined with the transcriptomics results. Genes that are transcriptionally regulated by Heatin and map to genes/genomic loci associated with Heatin sensitivity, and the genes coding for Heatin’s protein targets, will be studied in detail to understand their role in HTAR. Such analysis will deliver novel insights in the molecular networks how plants regulate HTAR. This knowledge will facilitate breeding programs aimed to develop crops that maintain high yields in a warming climate.