A Genetic Approach to Virulence in C. albicans

白色念珠菌毒力的遗传学方法

• 批准号: 6851481
• 负责人: SUZANNE M NOBLE
• 金额: $ 10.56万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-15 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6851481
• 关键词: Candida albicans; biotechnology; candidiasis; cell adhesion; cell line; cytokine; cytotoxicity; disease /disorder model; fungal genetics; fungal proteins; gene mutation; gene targeting; genetic library; genetic screening; host organism interaction; immune response; laboratory mouse; morphology; nitric oxide; parasite infection mechanism; pathologic process; polymerase chain reaction; site directed mutagenesis; virulence

DESCRIPTION (provided by applicant): Candida albicans is the most common fungal pathogen worldwide and yet there is limited understanding of its virulence mechanisms, particularly in comparison to those of bacterial pathogens. This poverty of understanding on the academic front is associated with a dearth of safe, effective clinical diagnostic and therapeutic tools. Forward genetic screens such as signature tagged mutagenesis have been fundamental in identifying the major virulence pathways in bacteria. Such screens have not been performed in C. albicans, however, because of experimental limitations imposed by a diploid genome and the absence of a complete mating cycle. I have recently developed methods and reagents that mitigate these obstacles. The goal of this proposal is to perform the first large-scale genetic analysis of virulence in C. albicans in order to identify and study the key determinants of pathogenesis in this organism. To accomplish these goals, I have the following specific aims: (1) Construct a signature-tagged knockout library of C. albicans homozygous disruption mutants; (2) Perform a genetic screen for virulence mutants in a murine infection model of disseminated Candidiasis; (3) Characterize the virulence defects of the mutants through secondary screens of specific steps in the pathogenesis cycle; and (4) Carry out detailed cell biological, molecular biological, and biochemical analysis of selected mutants of special interest. Results from this work should enhance our understanding of fungal pathogenesis and identify novel targets for antifungal therapy.

描述（由申请人提供）：白色念珠菌是全球最常见的真菌病原体，但对其毒力机制的了解有限，特别是与细菌病原体相比。这种对学术前沿的理解贫乏与缺乏安全，有效的临床诊断和治疗工具有关。正向遗传筛选，如签名标记的诱变已在确定细菌中的主要毒力途径的基础。这样的屏幕还没有在C中执行。然而，由于二倍体基因组和缺乏完整的交配周期所施加的实验限制，白色念珠菌的研究进展缓慢。我最近开发了一些方法和试剂来减轻这些障碍。这项计划的目标是进行第一次大规模的C。白念珠菌，以确定和研究在这种生物体的发病机制的关键决定因素。为了实现这些目标，本研究的具体目标如下：（1）构建一个带有特征标记的C.白色念珠菌纯合破坏突变体;（2）在弥散性念珠菌病的小鼠感染模型中进行毒力突变体的遗传筛选;（3）通过发病循环中特定步骤的二次筛选来表征突变体的毒力缺陷;（4）对选定的特别感兴趣的突变体进行详细的细胞生物学、分子生物学和生化分析。从这项工作的结果应该提高我们对真菌发病机制的理解，并确定新的抗真菌治疗的目标。