Genetic Control of C. albicans Biofilm Formation

白色念珠菌是一种主要的人类真菌病原体，可引起粘膜和深层组织感染。一个 白色念珠菌感染的重要危险因素是植入的医疗设备的存在，它提供了 形成生物膜的表面。生物膜为生物的生存创造了一个受保护的微环境 病原体。这里提出的研究的直接目标是定义关键的白色念珠菌基因和 管理生物膜形成的调控途径，长期目标是开发新的治疗方法 基于这一理解的战略。我们已经实施了一种新的策略来分析独特的C. 白念珠菌特征：转录因子功能调查。使用这种策略，我们创建了具有缺陷的菌株 每个转录因子基因，并测试菌株的表型缺陷。然后我们使用微阵列分析 确定对正在研究的表型有直接作用的靶基因。到目前为止，我们已经测试了 生物膜缺陷84个转录因子基因中每一个的纯合子插入突变。锌指 蛋白质Bcr1p是形成生物膜和表达一组表面蛋白基因所必需的 粘附素。我们将分析单个和多个目标基因突变以及在 生物被膜形成的检测。此外，我们将为其他生物膜调节剂识别靶基因，我们将 在我们的屏幕上定义。将对目标基因进行功能分析。最后，我们将在体外测试我们的 结果采用大鼠中心静脉导管模型进行体内生物被膜的形成。包括可行的属性 将监测负担、生物膜结构和基因表达谱。

Candida albicans is a major human fungal pathogen, causing both mucosal and deep tissue infections. A significant risk factor for C. albicans infection is the presence of an implanted medical device, which provides a surface for biofilm formation. The biofilm creates a protected microenvironment for survival of the pathogen. The immediate goal of studies here proposed is to define the key C. albicans genes and regulatory pathways that govern biofilm formation, with the long-term objective of developing new treatment strategies based upon this understanding. We have implemented a new strategy for analysis of unique C. albicans traits: a transcription factor function survey. With this strategy, we create strains with defects in each transcription factor gene and test the strains for phenotypic defects. We then use microarray analysis to identify target genes that have a direct role in phenotype under study. We have thus far tested homozygous insertion mutants in each of 84 transcription factor genes for biofilm defects. Zinc-finger protein Bcr1 p is required for biofilm formation and for expression of a group of surface protein genes and adhesins. We will analyze single and multiple target gene mutants as well as overexpressing strains in assays for biofilm formation. In addition, we will identify target genes for additional biofilm regulators that we define in our screen. Target genes will be subjected to functional analysis. Finally, we will test our in vitro results with a rat central venous catheter model for biofilm formation in vivo. Attributes including viable burden, biofilm architecture, and gene expression profiles will be monitored.