GhCAT1 improved the tolerance of cotton to Verticillium wilt revealed by genome-wide characterization of CAT genes family

Although catalase (CAT) proteins are well established players in plant immunity, their specific regulatory mechanisms in cotton's defense against Verticillium wilt remain unclear. To elucidate the functional roles of CAT proteins in plant defense systems, we conducted a systematic bioinformatics analysis encompassing physicochemical properties, phylogenetic relationships, protein structures, conserved domains, motif composition, duplication patterns, chromosomal localization, cis -regulatory elements, and expression profiles of CAT gene family members. RNA-seq data were employed to investigate correlations between GhCAT s and Verticillium dahliae ( V. dahliae ) infection. Furthermore, an RT-qPCR analysis showed that GhCAT1 exhibits tissue-specific and V. dahliae- responsive expression. Functional studies using VIGS in cotton and overexpression in A. thaliana confirmed its role in enhancing Verticillium wilt resistance by regulating pathogen-induced reactive oxygen species and jasmonic acid-dependent defense pathways. Yeast two-hybrid (Y2H) screening identified GhHSP70 as a direct interaction partner of GhCAT1 and a positive regulator of cotton Verticillium wilt. This research reveals new findings on CAT protein functions and supplies key genetic materials for breeding cotton varieties resistant to Verticillium wilt. • A total of 24 CAT genes were identified in four Gossypium spp . • GhCAT1 enhanced Verticillium wilt resistance via JA and ROS signaling pathways. • GhCAT1 interacted with GhHSP70 in yeast cells.