ClNOX1/ClNOXR‐mediated MAPK and cAMP‐PKA signalling pathways and ROS metabolism are involved in Curvularia lunata sexual reproduction and host infection

Abstract

NADPH oxidases (NOXs) and hydrogen peroxide (H 2 O 2 ) are involved in physiological and pathological processes, and cell fate decisions in organisms. However, regulatory mechanism of NOXs and the role of H 2 O 2 on fungal sexual reproduction and host infection remain largely unexplored. Here, we identified ROS metabolic genes and key signalling genes of MAPK and cAMP-PKA pathways in Curvularia lunata, which were NOX ClNOX1 and ClNOXR, superoxide dismutase ClSOD1 and catalase ClCAT4, redoxregulated transcription factor ClAP1, Ras small GTPases Clg2P, pheromone-response MAPK ClK1 and cAMP-PKA ClSCHA, and characterized the functions of these genes. The results showed that ClNOX1 localized to the plasma membrane. ClNOX1 and ClNOXR were involved in sexual reproduction and host infection via ClNOX1/ClNOXR-derived H 2 O 2 as well as MAPK and cAMP-PKA signalling pathways. H 2 O 2 acted as a signalling molecule to regulate sexual reproduction and host infection in C. lunata.

Contrasting effects of NADPH oxidases on the fungal hyphae growth and immune responses in Pleurotus ostreatus

“…Noxs have been demonstrated as necessary for a number of physiological functions and cellular differentiations in fungi, including the formation of sexual fruiting bodies, and the germination of ascospores, hyphal defense, and hyphal growth (Marschall and Tudzynski, 2016 ; Wang et al, 2022 ). In this study, we monitored the change in mycelial formation and branches caused by the two NADPH oxidases of P. ostreatus .…”

“…More recently, ROS have been recognized as key signaling molecules that regulate gene expression, hormone production, and secondary metabolite biosynthesis (Rohlfs, 2015 ; Xia et al, 2015 ; Tian et al, 2018 ; Shi et al, 2022 ). Moreover, ROS are involved in physiological and pathological processes in fungi, including fungal sexual reproduction, mechanical stress responses, biosynthesis of heat stress resistance triterpenes, host infection, and antipredator defenses (Liu et al, 2018 ; Wang et al, 2022 ).…”