Identification and characterization of genes responsive to drought and heat stress in rice (Oryza sativa L.)

Abstract

Rice is considered as a major source of food for most people worldwide. Global rice production is under threat as a result of adverse effects of heat and drought stress. It is therefore necessary to safeguard its sustainable production. This study was carried out to characterize differentially expressed genes (DEGs) under both drought and heat stresses in rice. 1001 DEGs were determined to show up-regulation under heat and drought stresses, while 1690 DEGs were commonly down-regulated. Functional classification analysis generated 22 and 37 related gene groups from the commonly up-regulated and down-regulated genes respectively. Functional characterization revealed 38.1% and 45.2% DEGs annotating for Biological Process, 53.2% and 59.2% DEGs were for Cellular Components and 54.8% and 52.4% DEGs were for Molecular Function in the up and down commonly regulated DEGs respectively. KEGG analysis demonstrated that most of the up-regulated DEGs were particularly enriched in metabolic pathways and in the biosynthesis of secondary metabolites, while the down regulated genes were mostly enriched in pathways involving ribosomes, and in purine and pyrimidine metabolisms. These results could be helpful in further analysis and understanding of heat and drought stress tolerance in rice.