RESPONSE REGULATOR GENE (CASSK1) OF CANDIDA ALBICANS

简介(摘自申请者摘要)：白色念珠菌最多 艾滋病患者的常见真菌病原体。感染最常见的是 口腔、食道或阴道的粘膜表面。尽管有 三氮唑类抗真菌药物问世，艾滋病患者的管理 白念珠菌耐药性的发展使念珠菌病复杂化。 非白念珠菌物种。合适的替代品的范围有限。 潜在的需要确定新的目标，这可以在 抗真菌药物的开发。我们的方法一直是以非哺乳动物为目标 磷蛋白是重要的信号转导途径的组成部分 白色念珠菌。为此，我们已经确定了一种两组分的组氨酸激酶 (CaHKI)和反应调节基因(CaSSK1)，这两个基因都是 生物体的毒力，因为每个基因中的敲除菌株都是无毒的 与亲本、杂合子和基因重组菌株进行比较。这个 这项提案的重点将放在第一个孤立的响应调节器CaSSKl上 来自白色念珠菌。我们强调这一基因的原因有两个。首先，它的 缺勤会导致无毒。第二，该基因的同源基因在 裂殖酵母为许多生物提供了必要的适应功能 应激条件，包括氧化、高温和蛋白质 抑制物应激。这项提议有三个具体目标。具体而言 目标1，体外研究将解决氧化应激问题。表达式将为 通过Northern分析和竞争性聚合酶链式反应同时测量 翻译后研究(磷酸化)。在特定目标2中，毒力 CaSSK1缺失菌株(及其单拷贝伴侣)的数量将在 念珠菌病的阴道和口腔模型。具体目标3将重点放在 差减法用于卡斯基普下游效应器的识别 杂交和酵母双杂交系统。这个项目的长期目标是 研究人员正在扩大抗C抗体的数量。白念珠菌目标和信息 这将导致高通量检测方法的发展 潜在的抑制剂。

DESCRIPTION (Adapted from applicant's abstract): Candida albicans is the most common fungal pathogen of AIDS patients. The infection most often involves the mucosal surfaces of the oral cavity, esophagus or vagina. In spite of the advent of triazoles as anti-fungals, management of AIDS patients with candidiasis is complicated by the development of drug-resistant C. albicans and non-albicans species. The spectrum of suitable alternatives is limited underlying the need to identify new targets, which can be exploited in the development of anti-fungals. Our approach has been to target non-mammalian phosphoproteins that are components of important signal transduction pathways of C albicans. To this end, we have identified a 2-component, histidine kinase (CaHKI) and response regulator genes (CaSSKl), both of which are essential for virulence of the organism, since knock-out strains in each gene were avirulent in comparison to parental, heterozygote and gene-reconstituted strains. The focus of this proposal will be on CaSSKl, the first response regulator isolated from C. albicans. Our reasons for emphasizing this gene are 2-fold. First, its absence results in avirulence. Second, a homologue of this gene in Schizosaccharomyces pombe provides essential adaptation functions for a number of stress conditions, including oxidative, high temperature and protein inhibitor stress. There are three specific aims in this proposal. In specific aim 1, in vitro studies will address oxidative stress. Expression will be measured by Northern analysis and competitive PCR in parallel with post-translational studies (phosphorylation). In specific aim 2, the virulence of CaSSKl-deleted strains (and their single-copy mates) will be evaluated in vaginal and oral models of candidiasis. Specific aim 3 will focus upon the identification of down-stream effectors of Casskip using subtractive hybridization and the yeast 2-hybrid system. The long-term objectives of this research are to expand the number of anti-C. albicans targets and information which will lead to the development of high-throughout assays for evaluating potential inhibitors.