Sterol Regulatory Element-Binding Protein, BbSre1, Controls Oxidative Stress Response, Peroxisome Division, and Lipid Homeostasis in an Insect Fungal Pathogen

Sterol regulatory element-binding protein, Sre1, regulatessterolbiosynthesis, lipid metabolism, hypoxia adaptation, and virulencein some fungi, even though its roles are varied in fungal species.However, few studies report its other functions in fungi. Here, wereport novel roles of Sre1 homolog, BbSre1, in the insect fungal pathogen, Beauveria bassiana, that regulates oxidative stressresponse, peroxisome division, and redox homeostasis. The gene disruptionstain showed increased sensitivity to oxidative stress, which wasin line with oxidative stress-induced-BbSre1 nuclear import and controlof antioxidant and detoxification-involved genes. The gene mutationalso inhibited peroxisome division, affected redox homeostasis, andimpaired lipid/fatty acid metabolism and sterol biosynthesis, whichwas verified by downregulation of their associated genes. These databroaden our understanding of role of Sre1, which regulates peroxisomedivision, antioxidant, and detoxification-involved genes for controlof redox homeostasis and oxidative stress response that links to lipid/fattyacid metabolism and sterol biosynthesis.

Automated summary

In the insect fungal pathogen, Beauveria bassiana, BbSre1 regulates oxidative stress response, peroxisome division, and redox homeostasis. Gene disruption inhibits peroxisome division, affects redox homeostasis, and impairs lipid/fatty acid metabolism and sterol biosynthesis. These findings broaden our understanding of the role of Sre1 in regulating oxidative stress and lipid metabolism.