Characterization of Strubbelig-Receptor Family (SRF) Related to Drought and Heat Stress Tolerance in Upland Cotton (Gossypium hirsutum L.)

Cotton is one of the world’s leading fiber crops, but climate change, drought, heat, and salinity have significantly decreased its production, consequently affecting the textile industries globally. To acclimate to these environmental challenges, a number of gene families involved in various molecular, physiological, and hormonal mechanisms play crucial roles in improving plants response to various abiotic stresses. One such gene family is the GhSRF, a Strubbelig-Receptor family (SRF), and member of the leucine-rich repeat (LRR-V) group. This family encodes leucine-rich repeat transmembrane receptor-like kinases (LRR-RLKs) and have not yet been explored in cotton. Arabidopsis thaliana Strubbelig-Receptor gene sequences were used as queries to identify the homologs in cotton, with subsequent support from the literature and functional prediction through online data. In the current study, a comprehensive genome-wide analysis of cotton was conducted, identifying 22 SRF putative proteins encoded by 22 genes. We performed the detailed analysis of these proteins, including phylogeny, motif and gene structure characterization, promoter analysis, gene mapping on chromosomes, gene duplication events, and chromosomal sub-cellular localization. Expression analysis of putative genes was performed under drought and heat stress conditions using publicly available RNAseq data. The qRT-PCR results showed elevated expression of GhSRF2, GhSRF3, GhSRF4, GhSRF10, and GhSRF22 under drought and heat stress. So, it could be speculated that these genes may play a role in drought and heat tolerance in cotton. These findings could be helpful in cotton breeding programs for the development of climate-resilient cultivars.