Targeting the regulatory mechanism of hyphae to lateral yeast growth as a novel therapeutic approach against candidiasis

针对菌丝对侧向酵母生长的调节机制作为对抗念珠菌病的新治疗方法

• 批准号: 10215503
• 负责人: PRIYA UPPULURI
• 金额: $ 39.32万
• 依托单位: LUNDQUIST INSTITUTE FOR BIOMEDICAL INNOVATION AT HARBOR-UCLA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-09 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10215503
• 关键词: Active Sites; Antifungal Agents; Attention; BRCA1 gene; BRCT Domain; Binding; Biological Assay; Blood Circulation; Candida; Candida albicans; Candidiasis; Carbon; Catheters; Cells; Coin; Complex; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Data; Development; Disease; Disseminated candidiasis; Distal; Down-Regulation; Drug resistance; Evaluation; FDA approved; Filament; Gene Deletion; Genes; Glucose; Goals; Growth; Human; Hyphae; In Vitro; Infection; Interruption; Invaded; Lateral; Lead; Libraries; Link; Mediating; Medical Device; Microbial Biofilms; Modeling; Morphogenesis; Mus; Mycoses; Organ; Pathogenesis; Pathway interactions; Patient-Focused Outcomes; Pharmaceutical Preparations; Pharmacology; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphorylation Site; Play; Process; Production; Protein Biochemistry; Protein Dephosphorylation; Protein Inhibition; Proteins; Regulation; Role; Saccharomycetales; Septal Region; Signal Transduction; Specificity; Sumoylation Pathway; Tissues; Virulence; Yeasts; analog; candidemia; high throughput screening; in vivo; inhibitor/antagonist; lead candidate; mouse model; novel; novel therapeutic intervention; novel therapeutics; pathogenic fungus; premature; prevent; protein protein interaction; ras Proteins; small molecule inhibitor; small molecule libraries; therapeutic target; trait

Abstract A single species Candida albicans, causes half of all invasive fungal infections in humans. The ability of C. albicans to switch reversibly between yeast and hyphe is a major virulence trait that helps it disseminate into the bloodstream (yeast) and invade target organs (filaments). Yeast to hyphae morphogenesis has been extensively studied and its regulation well understood. To the contrary, little is known about the reverse process: hyphae to yeast growth. C. albicans hyphae produce yeast cells from their lateral septal regions, coined as “lateral yeasts”. These lateral yeasts are always found with hyphae at the site of active infection, are the major cells that re- enter the bloodstream and establish distal foci of infection. In fact, lateral yeast cells released from the hyphal layers of biofilm-contaminated catheters have direct access into the bloodstream. We identified the first regulator of hyphae-to-lateral yeast growth, PES1 and have shown that blocking the process (by depleting PES1 in vivo) can abrogate disseminated candidiasis as well as biofilm- associated candidemia. Nothing is known on the regulatory aspects pf PES1. Our preliminary studies show that phosphorylation of Pes1 by Ras-PKA inhibits lateral yeast growth while its dephosphorylation by a Ras- linked phosphatase Yvh1 activates lateral yeast emergence from hyphae and induces biofilm dispersal. Using PES1 as a target for identifying small molecule inhibitors of lateral yeast growth, identified alexidine dihydrochloride that directly inhibited both Pes1 and Yvh1 and protected mice from biofilm-associated disseminated candidiasis. Here, using protein biochemistry assays, we propose to delineate how signaling through Ras-PKA regulates Pes1. We will identify other cognate regulators that interact with Pes1 to control lateral yeast growth, and use this information to discover novel compounds that can interrupt hyphae to lateral yeast growth and disseminated candidiasis. Ultimately, better outcomes for patients with indwelling medical devices is the goal of this application.

抽象的 单一物种白色念珠菌引起人类所有侵袭性真菌感染的一半。 C的能力。 白色念珠菌在酵母和菌丝之间可逆地转换是一个主要的毒力特征，有助于其传播到 进入血液（酵母）并侵入目标器官（丝）。酵母菌到菌丝的形态发生 进行了广泛的研究并且对其调节进行了很好的理解。相反，人们对相反的情况知之甚少 过程：菌丝到酵母生长。白色念珠菌菌丝从其侧隔膜区域产生酵母细胞， 被称为“侧向酵母”。这些侧向酵母总是在活跃感染部位发现有菌丝， 是重新进入血流并建立远端感染灶的主要细胞。事实上，侧向酵母 从生物膜污染的导管的菌丝层释放的细胞可以直接进入 血流。我们确定了第一个菌丝到侧向酵母生长的调节因子 PES1，并表明 阻断这一过程（通过体内消耗 PES1）可以消除播散性念珠菌病以及生物膜。 相关的念珠菌血症。 PES1 的监管方面一无所知。我们的初步研究表明 Ras-PKA 对 Pes1 的磷酸化会抑制酵母的横向生长，而 Ras-PKA 对 Pes1 的去磷酸化会抑制酵母的横向生长。 连接磷酸酶 Yvh1 激活酵母菌从菌丝中横向出现并诱导生物膜分散。使用 PES1作为识别酵母横向生长小分子抑制剂的靶点，鉴定出alexidine 二盐酸盐直接抑制 Pes1 和 Yvh1 并保护小鼠免受生物膜相关的影响 播散性念珠菌病。在这里，我们建议使用蛋白质生物化学测定来描述信号传导如何 通过 Ras-PKA 调节 Pes1。我们将确定与 Pes1 相互作用的其他同源调节因子来控制 侧向酵母生长，并利用这些信息来发现可以中断菌丝侧向生长的新化合物 酵母菌生长和传播念珠菌病。最终，为留置医疗的患者带来更好的结果 devices 是此应用程序的目标。