Genome-Wide Investigation and Co-Expression Network Analysis of SBT Family Gene in Gossypium .

Subtilases (SBTs), which belong to the serine peptidases, control plant development by regulating cell wall properties and the activity of extracellular signaling molecules, and affect all stages of the life cycle, such as seed development and germination, and responses to biotic and abiotic environments. In this study, 146 , 138 , 89 and 84 SBTs were identified and divided into six subfamilies. Cotton SBTs are unevenly distributed on chromosomes. Synteny analysis showed that the members of SBT1 and SBT4 were expanded in cotton compared to . Co-expression network analysis showed that six SBT gene family members were in a network, among which five SBT1 genes and their and direct homologues were down-regulated by salt treatment, indicating that the co-expression network might share conserved functions. Through co-expression network and annotation analysis, these SBTs may be involved in the biological processes of auxin transport, ABA signal transduction, cell wall repair and root tissue development. In summary, this study provides valuable information for the study of SBT genes in cotton and excavates SBT genes in response to salt stress, which provides ideas for cotton breeding for salinity resistance.