Transcription Factor StHRAV1 Negatively Regulates Thermotolerance by Modulating ROS Accumulation in Potato.

Area of Science:

• Plant Biology
• Molecular Genetics
• Stress Physiology

Background:

• High-temperature stress poses a significant threat to global potato production.
• The underlying molecular mechanisms of plant thermotolerance are not fully elucidated.

Purpose of the Study:

• To identify and characterize novel genes involved in potato thermotolerance.
• To investigate the function of the RAV family gene StHRAV1 in response to heat stress.

Main Methods:

• Gene expression analysis under high-temperature stress.
• Gene silencing (RNA interference) in potato.
• Physiological assays (ion leakage, ROS levels, antioxidant capacity).
• RNA sequencing (RNA-seq) for pathway analysis.
• DNA affinity precipitation sequencing (DAP-seq) and dual-luciferase assays.
• Heterologous expression in *Arabidopsis thaliana*.

Main Results:

• A novel potato RAV family gene, StHRAV1, was identified, with its expression suppressed by heat stress.
• Suppression of StHRAV1 enhanced potato thermotolerance, indicated by reduced ion leakage, lower ROS, and improved antioxidant capacity.
• StHRAV1 functions as a transcriptional repressor, directly regulating antioxidant genes.
• Overexpression of StHRAV1 in *Arabidopsis* impaired thermotolerance by increasing ROS accumulation.

Conclusions:

• StHRAV1 plays a crucial role in repressing thermotolerance in potato.
• Modulation of StHRAV1 offers a potential strategy for enhancing crop heat resistance.
• These findings contribute to understanding the role of RAV transcription factors in plant oxidative stress responses.