Systematic Analysis of Morphogenesis, Commensalism, and Virulence in a Leading Human Fungal Pathogen

主要人类真菌病原体的形态发生、共生性和毒力的系统分析

• 批准号: 9751202
• 负责人: LEAH Elizabeth Cowen
• 金额: $ 54.51万
• 依托单位: UNIVERSITY OF TORONTO
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9751202
• 关键词: Address; Alleles; Aneuploidy; Antifungal Agents; Antifungal Therapy; Ascomycota; Biological Assay; Biology; Candida; Candida albicans; Cells; Cellular Morphology; Cellular Structures; Clinical; Collaborations; Collection; Communities; Complex; Cues; Cytolysis; Data Set; Development; Diploidy; Drug Targeting; Drug resistance; Environment; Essential Genes; Filament; Foundations; Gastrointestinal tract structure; Gene Deletion; Gene Expression; Genes; Genetic; Genetic Transcription; Genome; Genomic Library; Genomic approach; Genomics; Goals; Growth; HIV; Health; Human; Image Analysis; Immune; Immune system; Immunocompromised Host; In Vitro; Incidence; Individual; Infection; Investments; Laboratories; Libraries; Life; Link; Machine Learning; Malignant Neoplasms; Methods; Molecular; Morphogenesis; Mus; Mutation; Mycoses; Nosocomial Infections; Organ Transplantation; Organism; Outcome; Pathogenesis; Pathogenicity; Pharmaceutical Preparations; Phenotype; Process; Property; Publishing; Resistance development; Resolution; Resources; Sepsis; Solid; Symbiosis; Systemic infection; Testing; Tetracyclines; Therapeutic; Toxic effect; Virulence; Work; Yeast Model System; Yeasts; attributable mortality; cancer therapy; cancer transplantation; combat; computational platform; fitness; functional genomics; fungus; gene replacement; genome-wide; genomic platform; high resolution imaging; human disease; immune function; improved; insight; member; mortality; mucosal microbiota; mutant; new therapeutic target; next generation sequencing; novel; novel therapeutic intervention; novel therapeutics; pathogen; pathogenic fungus; patient population; programs; promoter; quantitative imaging; response; trait; unpublished works

The impact of fungal pathogens on human health is devastating. They infect billions of people worldwide, and kill more than 1.5 million each year. The most vulnerable are people with reduced immune function, such as those with HIV or those undergoing immune suppressing treatments for cancer or organ transplants. One of the most pervasive fungal pathogens is Candida albicans, which kills almost 40% of people suffering from bloodstream infections. Treating these infections is extremely difficult, as fungi are closely related to humans and there are very few drugs that kill the fungus without host toxicity. With the emergence of drug resistance, the development of new therapeutic strategies is now crucial. To address this important clinical need and identify new antifungal drug targets, it is critical to uncover mechanisms that enable C. albicans to cause life-threatening human disease. We are one of the first academic labs to obtain a powerful resource that will allow us to test the function of almost every gene in the C. albicans genome. This resource includes a collection of double barcoded heterozygous mutants covering ~90% of the genome, and a collection of strains covering ~40% of the genome where the expression of the remaining wild-type allele of a gene is governed by the tetracycline-repressible promoter. This resource provides an unprecedented opportunity to identify genes that control key virulence traits such as morphogenesis. It also enables the identification of determinants of commensalism and virulence, and to further elucidate the molecular mechanisms involved. We have optimized a functional genomics platform for massively parallel analysis of fungal virulence traits using next generation sequencing to quantify the relative proportion of each barcoded strain in pooled assays. We have also optimized high- resolution image analysis of cellular morphology and structures, and assays for identifying genes important for commensalism, virulence, and interaction with host immune cells. Our studies will provide the first global analysis of C. albicans morphogenesis, commensalism, and virulence. Our studies will: 1) develop a computational platform to predict C. albicans essential genes, and expand the collection of tetracycline-repressible conditional expression strains to cover most non-essential genes, since genes required for pathogen viability in vitro provide little insight into mechanisms of host adaptation or virulence; 2) identify novel regulators of key virulence traits such as morphogenesis; and 3) identify determinants of C. albicans host adaptation and virulence on a genome scale. This work will provide an expanded functional genomics resource to advance the field, and will leverage this resource to elucidate the genes and genetic networks governing morphogenesis and virulence. This will reveal new strategies to cripple fungal pathogens, and drug targets to improve clinical outcome.

真菌病原体对人类健康的影响是毁灭性的。他们感染了数十亿人 全球，每年杀死150万以上。最脆弱的是免疫力减少的人 功能，例如患有艾滋病毒或接受免疫抑制癌症或器官治疗的功能 移植。最普遍的真菌病原体之一是白色念珠菌，杀死了几乎40％的人 患有血液感染。治疗这些感染非常困难，因为真菌密切 与人类有关，很少有药物在没有宿主毒性的情况下杀死真菌。随着出现 耐药性，新的治疗策略的发展现在至关重要。解决这个重要的 临床需求并确定新的抗真菌药物靶标，发现能够启用的机制至关重要 白色念珠菌引起威胁生命的人类疾病。 我们是第一个获得强大资源的学术实验室之一，该实验室将使我们能够测试功能 白色念珠菌基因组中的几乎每个基因。此资源包括双条形码的集合 覆盖了约90％基因组的杂合突变体，覆盖约40％的菌株的杂合突变体 其中基因剩余的野生型等位基因的表达由四环素抑制作用控制 发起人。该资源提供了一个前所未有的机会来识别控制关键毒力的基因 诸如形态发生的特征。它还可以识别共同主义的决定因素和 毒力，并进一步阐明所涉及的分子机制。我们已经优化了功能 用于使用下一代测序对真菌毒力性状进行大规模平行分析的基因组学平台 量化合并测定中每个条形码应变的相对比例。我们还优化了高 细胞形态和结构的分辨率图像分析，以及鉴定基因重要的测定 与宿主免疫细胞的相称，毒力和相互作用。我们的研究将提供第一个全球 白色念珠菌形态发生，相称和毒力的分析。 我们的研究将：1）开发一个计算平台来预测白色念珠菌的基本基因，并 扩展四环素可抑制条件表达菌株的收集以覆盖大多数非必需品 基因，由于体外病原体所需的基因几乎没有洞察宿主的机制 适应或毒力； 2）确定关键毒力性状（例如形态发生）的新型调节因子； 3） 确定白色念珠菌在基因组量表上宿主适应和毒力的决定因素。这项工作将提供 扩展的功能基因组学资源以推进该领域，并将此资源利用 阐明控制形态发生和毒力的基因和遗传网络。这将揭示 削弱真菌病原体的新策略和药物靶标，以改善临床结果。