GENOME-WIDE ANALYSIS AND IDENTIFICATION OF HSF (HEAT SHOCK TRANSCRIPTION FACTOR) GENES IN COFFEE (COFFEE ARABICA L.) UNDER ABIOTIC STRESS

Abstract

Coffee is a livelihood source for millions of farmers and plays a significant role in the economy of many coffee-producing countries. Abiotic stresses, such as drought and high temperature, however, negatively impact coffee growth, productivity, and bean quality. Heat shock factors (HSFs) play a crucial role in the plant response to heat and other abiotic stresses. However, there is still not a lot of detailed knowledge about the HSF gene family in Coffea arabica. In this study, a genome-wide search was performed to find and characterize the genes of HSF from C.arabica. A total of 59 putative CaHSF genes have been identified and characterized according to their physicochemical properties, chromosomal distribution, gene structure, conserved motifs, phylogenetic relationship, duplication event, synteny, cis-regulatory elements, and protein–protein interactions. The genes identified for CaHSF were assigned to different scaffolds of the genome, and they had different sizes, molecular mass, isoelectric point, GRAVY value, and aliphatic index of their protein. Through the relationships induced by the phylogenetic and conserved-domain analyses, and by their conservation, it was possible to get insight into the evolution of the proteins of the CaHSF family. Abiotic stress response, hormone signaling, and light regulation were noted to have several cis-regulatory elements associated with them in the promoter analysis and hence the possible role of the CaHSF genes in stress adaptation. Duplication and synteny analyses also showed that gene duplication played a role in the diversification and expansion of the CaHSF gene family in C. arabica. Overall, this study is a thorough genomic analysis of the CaHSF gene family, which can serve as a basis for future functional studies for understanding the molecular mechanism of abiotic stress tolerance in coffee.