In-silico identification, characterization and expression analysis of salt overly sensitive-2 (SOS2) gene family in Gossypium hirsutum L. against abiotic stresses

Gossypium hirsutum backbone of economy of many countries; is primarily grown for production of fiber. This is the first genome-wide analysis of GhSOS2 gene family in G. hirsutum. Primary function of SOS2 is ion homeostasis and plays functional role in osmotic stress as well as drought, effecting the development and growth of plant. During this study 21 GhSOS2 proteins were identified in G. hirsutum via BLASTp against 4 AtSOS2 protein sequences from Arabidopsis thaliana as query. Two distinct domains (P-kinase and NAF domain) were conserved in all identified GhSOS2 proteins. Gene architecture and phylogenetic study depicts the evolutionary conservation and divergence among gene paralogs and their equal distribution among both genome as a result of synteny and duplication events. A total of 10 Conserved motif are detected in all 21 GhSOS2 genes. Promotor analysis confirms the existence of hormones responsive elements GRE, ABARE, STRE, and other regulatory factors in GhSOS2 elucidating their potential contribution against abiotic stresses. Furthermore, physiochemical properties and PPI also highlights the role of GhSOS2 against drought and salinity. Data obtained by RNA-seq analysis revealed a gene subset with significant expression based on FPKM metrics at different intervals. Upon qPCR validation; GhSOS2-8, GhSOS2-13, and GhSOS2-21 were markedly up-regulated under both salt and drought stress at immediate and late hours. This study lays groundwork for functional validation of GhSOS2 in genetic modification of abiotic resistant G. hirsutum cultivars.