Rajesh-Khanna Dhanabala-Subhiksha, Piña Páez Carolina G, Dolan Elora G, Mirpuri Kiran S, Staijch Jason E, Hogan Deborah A
Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA.
Department of Microbiology & Plant Pathology and Institute for Integrative Genome Biology, University of California-Riverside, Riverside, California, USA.
bioRxiv. 2025 May 5:2025.05.04.652153. doi: 10.1101/2025.05.04.652153.
Infections caused by the emerging pathogenic yeast can be difficult to manage due to multi-drug resistance. Resistance to the frontline antifungal fluconazole (FLZ) in spp. is commonly acquired through gain-of-function (GOF) mutations in the gene encoding the transcription factor Mrr1. These activated Mrr1 variants enhance FLZ efflux via upregulation of the multi-drug transporter gene . Recently, it was reported that, unlike in the well-studied species, and with activated Mrr1 also have high expression of , which encodes another multi-drug transporter with overlapping but distinct transported substrate profiles and Cdr1-dependent FLZ resistance. To better understand the mechanisms of Mrr1 regulation of and , and other co-regulated genes, we performed CUT&RUN analysis of Mrr1 binding sites. Mrr1 bound the promoter regions of and as well as , which encodes another transporter capable of FLZ efflux. Mdr1 and Cdr1 independently contributed to the decreased susceptibility of the strains against diverse clinical azoles and other antifungals, including 5-flucytosine. A consensus motif, CGGAGWTAR, enriched in Mrr1-bound DNA was also conserved upstream of and across species including . CUT&RUN and RNA-seq data were used to define the Mrr1 regulon which includes genes involved in transport, stress responses, and metabolism. Activated and inducible Mrr1 bound similar regions in the promoters of Mrr1 regulon genes. Our studies provide new evolutionary insights into the coordinated regulation of multi-drug transporters and potential mechanism(s) that aid secondary resistance acquisition in emerging .
由新兴致病酵母引起的感染由于多重耐药性而难以控制。在 spp. 中，对一线抗真菌药物氟康唑（FLZ）的耐药性通常是通过编码转录因子 Mrr1 的基因中的功能获得性（GOF）突变获得的。这些激活的 Mrr1 变体通过上调多药转运蛋白基因来增强 FLZ 外排。最近有报道称，与研究充分的 物种不同，具有激活的 Mrr1 的 和 也具有 的高表达， 编码另一种具有重叠但不同转运底物谱和依赖 Cdr1 的 FLZ 耐药性的多药转运蛋白。为了更好地理解 Mrr1 对 和 以及其他共同调控基因的调控机制，我们对 Mrr1 结合位点进行了 CUT&RUN 分析。Mrr1 结合了 和 以及 的启动子区域， 编码另一种能够外排 FLZ 的转运蛋白。Mdr1 和 Cdr1 独立导致 菌株对多种临床唑类和其他抗真菌药物（包括 5-氟胞嘧啶）的敏感性降低。在 Mrr1 结合的 DNA 中富集的共有基序 CGGAGWTAR 在包括 在内的物种的 和 上游也保守。CUT&RUN 和 RNA 测序数据用于定义 Mrr1 调控子，其包括参与转运、应激反应和代谢的基因。激活的和可诱导的 Mrr1 结合 Mrr1 调控子基因启动子中的相似区域。我们的研究为多药转运蛋白的协同调控以及有助于新兴 获得继发性耐药的潜在机制提供了新的进化见解。
