Integrative transcriptomic and gene co-expression network analysis of host responses upon Verticillium dahliae infection in Gossypium hirsutum

Worldwide, Verticillium wilt is among the major harmful diseases in cotton production, causing substantial reduction in yields. While this disease has been extensively researched at the molecular level of the pathogen, the molecular basis of V. dahliae host response association is yet to be thoroughly investigated. In this study, RNA-seq analysis was carried out on V. dahliae infected two Gossypium hirsutum L. cultivars, Xinluzao-36 (susceptible) and Zhongzhimian-2 (disease resistant) for 0 h, 24 h, 72 h and 120 h time intervals. Statistical analysis revealed that V. dahliae infection elicited differentially expressed gene responses in the two cotton varieties, but more intensely in the susceptible cultivar than in the resistant cultivars. Data analysis revealed 4241 differentially expressed genes (DEGs) in the LT variety across the three treatment timepoints whereas 7657 in differentially expressed genes (DEGs) in the Vd592 variety across the three treatment timepoints. Six genes were randomly selected for qPCR validation of the RNA-Seq data. Numerous genes encompassed in disease resistance and defense mechanisms were identified. Further, RNA-Seq dataset was utilized in construction of the weighted gene co-expression network and 11 hub genes were identified, that encode for different proteins associated with lignin and immune response, Auxin response factor, cell wall and vascular development, microtubule, Ascorbate transporter, Serine/threonine kinase and Immunity and drought were identified. This significant research will aid in advancing crucial knowledge on virus-host interactions and identify key genes intricate in G. hirsutum L. resistance to V. dahliae infection.