Two sirtuin proteins, Hst3 and Hst4, modulate asexual development, stress tolerance, and virulence by affecting global gene expression in Beauveria bassiana .

. Deletion of these sirtuin homologs led to reduced conidial yield, increased sensitivity to osmotic and oxidative stresses, impaired DNA damage repair processes, and decreased fungal virulence. Transcriptomic analyses showed differential expression of numerous genes involved in secondary metabolism, detoxification, transporters, and virulence-related factors, potentially uncovering new targets for manipulation and optimization of fungal biocontrol agents. Our study also emphasizes the significance of sirtuins as key regulators in fungal biology and highlights their potential as promising targets for the development of novel antifungal strategies.