Gene expression during cold and heat shock in wheat

Area of Science:

• Plant Molecular Biology
• Stress Physiology
• Agricultural Science

Background:

• Wheat (Triticum aestivum L.) exhibits varying tolerance to environmental stresses like cold and heat.
• Understanding the molecular mechanisms underlying stress response is crucial for crop improvement.

Purpose of the Study:

• To compare translatable messenger RNA (mRNA) expression in winter and spring wheat under cold and heat stress.
• To identify specific mRNAs associated with freezing tolerance development.

Main Methods:

• Isolation and translation of polyadenylated RNA from wheat crown and leaf tissues.
• Two-dimensional SDS-PAGE and autoradiography to analyze in vitro translation products.
• Comparison of mRNA expression patterns between cold- and heat-stressed wheat genotypes.

Main Results:

• Low temperature stress induced two groups of mRNAs: transient (18 mRNAs) and sustained (53 mRNAs).
• A subset of sustained mRNAs (34) showed higher expression in freezing-tolerant winter wheat compared to spring wheat.
• Heat shock (40°C) induced 50 mRNAs, largely distinct from those induced by cold stress.

Conclusions:

• Different sets of mRNAs are activated by cold and heat stress in wheat.
• Specific mRNA expression patterns correlate with the capacity for freezing tolerance in wheat genotypes.
• Distinct genetic systems likely regulate responses to cold and heat stress in wheat.