OsRHS Negatively Regulates Rice Heat Tolerance at the Flowering Stage by Interacting With the HSP Protein cHSP70-4

Area of Science:

• Plant Biology
• Genetics
• Agricultural Science

Background:

• Heat stress during rice flowering significantly reduces grain yield.
• Identifying genes controlling heat tolerance at this stage is crucial for crop improvement.

Purpose of the Study:

• To investigate the function of the heat-induced gene reduced heat stress tolerance 1 (OsRHS) in rice.
• To understand the molecular mechanisms underlying rice heat tolerance during flowering.

Main Methods:

• Gene overexpression and RNAi silencing of OsRHS.
• Gene knockout and complementation assays.
• Protein-protein interaction studies with heat shock proteins (HSPs).
• Analysis of gene expression under heat stress.

Main Results:

• Overexpression of OsRHS reduced heat tolerance, while its silencing or knockout enhanced it without affecting seed setting rate.
• OsRHS interacts with cHSP70-4, and knockout of cHSP70-4 also increased heat tolerance.
• Heat stress strengthens the OsRHS-cHSP70-4 interaction.
• OsRHS negatively regulates stress-related gene expression under heat stress.

Conclusions:

• OsRHS and cHSP70-4 are key players in modulating rice heat tolerance during flowering.
• OsRHS acts as a negative regulator of heat stress response.
• Targeting OsRHS offers a potential strategy for developing heat-resilient rice varieties.