PATHOGENESIS OF CANDIDA GLABRATA IN THE URINARY TRACT

该提案的长期目标是全面分析致病性酵母菌在尿路中定植和持久性所需的毒力因子。光滑念珠菌和白色念珠菌是导致真菌尿以及阴道、口咽和全身念珠菌病的两种主要微生物。关于念珠菌在泌尿道定植或持续存在的因素知之甚少。在这里，我们将采取遗传学的方法来了解念珠菌感染的尿路。与C. albicans、假丝酵母C. glabrata是一种遗传学方法来了解念珠菌感染的尿路。与C. albicans、假丝酵母C. glabrata是单倍体，使其成为使用已经建立的遗传工具进行毒力遗传分析的极好模型。我们建议首先确定基因，特别是涉及在尿路定植和持久性。我们将使用两种不同的互补的全球方法。首先，我们在C. glabrata将用于筛选一组。glabrata突变体的那些不能在膀胱中定殖和复制。其次，将构建与GFP融合的基因组片段文库，并筛选在膀胱或肾脏中特异性诱导的启动子，但不在实验室条件下。这两种全局方法将产生与宿主相互作用相关的重叠基因组。最后，我们将详细分析任何已确定的基因在尿路感染中的作用。首先根据序列同源性对已鉴定的基因进行优先级排序，以便进一步研究。突变体将通过一组体外试验表征宿主相互作用的不同方面，包括粘附宿主组织、与吞噬细胞相互作用以及在模拟膀胱环境的体外条件下生长。不同的基因可能在感染的不同方面起作用，只有在感染的动力学已知的情况下才能进行分析。因此，我们也将使用我们的签名标记的菌株来分析UTI感染的野生型和突变株的C。glabrata，区分初始定殖和生长。这些方法将提供对酵母-宿主相互作用的不同方面的深入了解，以及对有助于真菌UTI的过程的更好理解，最终允许增强治疗干预。

The long term objective of this proposal is a comprehensive analysis of virulence factors in pathogenic yeast required for colonization and persistence in the urinary tract. Candida glabrata and Candida albicans are the two major organisms responsible for funguria, as well as vaginal, oropharyngeal and systemic candidiasis. Little is known about the factors that allow Candida to colonize or persist in the urinary tract. Here, we will take a genetic approach to understanding Candida infections of the urinary tract. Unlike C. albicans, C. glabrata is a genetic approach to understanding Candida infections of the urinary tract. Unlike C. albicans, C. glabrata is haploid making it an excellent model for genetic analysis of virulence using already established genetic tools. We propose first to identify genes specifically involved in colonization and persistence in the urinary tract. We will use two different complementary global approaches. First, a variation of signature-tagged mutagenesis that we have established in C. glabrata will be used to screen a bank of . glabrata mutants for those that are unable to colonize and replicate in the bladder. Second, a library of genomic fragments fused to GFP will be constructed and screened for promotes specifically induced in the bladder or kidney but not under laboratory conditions These two global approaches will yield overlapping sets of genes relevant to the host interaction... Lastly, we will analyze in detail the role of any identified genes in urinary tract infections. Identified genes will first be prioritized for further study based on sequence homology. Mutants will be characterized with a set of in vitro assays for different aspects of the host interaction, including adherence to host tissue, interaction with phagocytes and growth under in vitro conditions mimicking the bladder environment. Different genes are likely to have roles in different aspects of infection which can be assayed only if the dynamics of the infection are known. We will therefore also use our signature-tagged strains to analyze the dynamics of UTI infection for wild type and mutant strains of C. glabrata, distinguishing between initial colonization and outgrowth. These approaches will provide insight into diverse aspects of the yeast- host interaction and an improved understanding of the processes contributing to fungal UTI, ultimately permitting enhanced therapeutic intervention.