<i>Candida glabrata</i> maintains two <i>HAP1</i> ohnologs, <i>HAP1A</i> and <i>HAP1B</i> , for distinct roles in ergosterol gene regulation to mediate sterol homeostasis under azole and hypoxic conditions

Invasive and drug-resistant fungal infections pose a significant public health concern. <i>Candida glabrata</i>, a human fungal pathogen, is often difficult to treat due to its intrinsic resistance to azole antifungal drugs and its capacity to develop clinical drug resistance. Therefore, understanding the pathways that facilitate fungal growth and environmental adaptation may lead to novel drug targets and/or more efficacious antifungal therapies. While the mechanisms of azole resistance in <i>Candida</i> species have been extensively studied, the roles of zinc cluster transcription factors, such as Hap1A and Hap1B, in <i>C. glabrata</i> have remained largely unexplored until now. Our research shows that these factors play distinct yet crucial roles in regulating ergosterol homeostasis under azole drug treatment and oxygen-limiting growth conditions. These findings offer new insights into how this pathogen adapts to different environmental conditions and enhances our understanding of factors that alter drug susceptibility and/or resistance.