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

真菌病原体对人类健康的影响是毁灭性的。它们感染了数十亿人 全球范围内，每年杀死超过150万人。最脆弱的是免疫力低下的人 功能，如那些与艾滋病毒或那些接受免疫抑制治疗的癌症或器官 移植最普遍的真菌病原体之一是白色念珠菌，它几乎杀死了40%的人 患有血液感染治疗这些感染是非常困难的，因为真菌是密切相关的。 与人类有关，很少有药物能杀死真菌而不对宿主产生毒性。的出现 为了解决耐药性问题，开发新的治疗策略现在至关重要。处理这一重要 临床需要和确定新的抗真菌药物靶点，关键是要揭示机制，使 C.白色念珠菌导致危及生命的人类疾病。 我们是第一个获得强大资源的学术实验室之一，这将使我们能够测试该功能 几乎所有的基因都在C.白色念珠菌基因组。此资源包括一个双条形码的集合 杂合突变体覆盖约90%的基因组，以及覆盖约40%的基因组的菌株集合 其中基因的剩余野生型等位基因的表达由四环素抑制的 启动子这一资源为确定控制关键毒力的基因提供了前所未有的机会 例如形态发生。它还使人们能够确定反犹太主义的决定因素， 毒力，并进一步阐明相关的分子机制。我们优化了一个函数 利用下一代测序技术大规模并行分析真菌毒力性状的基因组学平台， 定量合并测定中每种条形码化菌株的相对比例。我们还优化了高- 细胞形态和结构的分辨率图像分析，以及用于鉴定对 寄生性、毒力和与宿主免疫细胞的相互作用。我们的研究将提供第一个全球性的 分析C.白色念珠菌形态发生、念珠菌性和毒力。 我们的研究将：1）开发一个计算平台来预测C。白色念珠菌必需基因，和 扩大四环素抑制性条件表达菌株的收集范围，以涵盖大多数非必需的 基因，因为病原体在体外生存所需的基因提供了很少的洞察宿主的机制 适应或毒力; 2）鉴定关键毒力性状如形态发生的新调节剂;和3） 确定C的决定因素。白念珠菌宿主适应性和毒力的基因组规模。这项工作将提供 一个扩展的功能基因组学资源，以推进该领域，并将利用这一资源， 阐明了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改善临床结果的药物靶点。

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.