Role of heat shock proteins in drought tolerance mechanism in chickpea

Chickpea is highly drought-resistant and can withstand high temperatures and prolonged droughts, making it suitable for climate conditions in Ukraine, so increasing of chickpea drought tolerance is highly important.Heat shock proteins (HSP), especially small HSP (sHSP), are diverse and have evolved significantly, indicating their ancient origins and critical roles in plant stress responses.These proteins have undergone extensive gene duplication and divergence, leading to various functions and stress responses across different plant species.sHSP have conserved -crystallin domain, and typically form large oligomeric complexes essential for their chaperone activity.They prevent protein aggregation and assist in protein refolding under stress.sHSPs are found in various cellular compartments, indicating specialized roles in different cellular environments.HSP regulation is controlled by heat shock factors (HSF), which activate in response to stress and bind to heat shock elements in HSP promoters.HSF are regulated at multiple levels, ensuring balanced stress adaptation and recovery.Identified HSF in chickpea are significantly upregulated during heat stress, indicating their critical role in stress tolerance.HSP, including sHSP like CaHSP18.5 and CaHSP22.7, are upregulated under drought stress in chickpea, contributing to improved membrane stability and antioxidative protection.Proteomic and transcriptomic analyses have identified key HSP that are differentially expressed in drought-tolerant chickpea genotypes.Cross-priming with mild drought stress can enhance the expression of HSP, providing potential strategy for improving both drought and heat tolerance in chickpea.MicroRNAs (miRNA) play crucial roles in regulating HSPs and other stress-responsive genes.miR408 and miR398 are significant in enhancing drought and heat tolerance by targeting specific genes and modulating HSP expression.The differential expression of various miRNA under drought conditions highlights their importance in multiple regulatory pathways.