Cryptococcus gatti mating loci; mapping and gene study

加蒂隐球菌交配位点；

• 批准号: 6682120
• 负责人: VISHNU CHATURVEDI
• 金额: $ 7.81万
• 依托单位: WADSWORTH CENTER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6682120
• 关键词: Cryptococcus neoformans; biochemical evolution; biological signal transduction; biotechnology; cryptococcosis; functional /structural genomics; fungal genetics; gene targeting; genetic library; genetic mapping; genetic screening; laboratory mouse; microorganism reproduction; molecular genetics; mutant; nucleic acid purification; nucleic acid sequence; plasmids; transcription factor; transfection; virulence

DESCRIPTION (provided by applicant): Cryptococcus neoformans (Cn) causes cryptococcosis, a fungal meningoencephalitis. The pathogen has genetically distinct varieties (var. grubii, var. neoformans, and var. gattii) and mating types (MATalpha and MATalpha). These varieties elicit different host responses in normal and immunocompromised individuals. The mechanisms underlying these pathogenic differences are not well understood. Cn var. grubii is the most common cause of cryptococcosis worldwide; var. neoformans infections have been mostly recognized in Europe. Both primary and opportunistic infections due to var. gattii were till recently reported from Australia, Southeast Asia and South America with rare reports from North America. This epidemiology has changed dramatically with the current report of a major var. gattii outbreak in humans and animals in British Columbia, Canada. Currently, Cn mating is under intensive investigations to define the observed linkage between fungal virulence and MATalpha, and to understand the regulatory signaling pathways. Recently, MATalpha and MATalpha loci from var. grubii and var. neoformans were mapped, and many MAT-specific genes are under intensive study for their role in fungal biology and virulence. However, these powerful molecular genetic analyses have not yet been extended to var. gattii, which will be essential for better understanding of its pathogenesis and the development of more effective therapy. The emerging knowledge from var. grubii and var. neoformans was applied in this laboratory to develop DNA based rapid tests to identify all varieties and mating types; further study of MATalpha/alpha pheromones revealed variety specificity, different copy numbers, and chromosomal locations, and a potential for cross-variety mating and/or hybridization. The current proposal builds upon these investigations by focusing exclusively on var. gattii. Our specific goals are: (i) identification, mapping and phylogenetic studies of genes comprising MATalpha locus, and (ii) characterization of var. gattii STE12alpha cDNA, construction of gene knockout mutants, and study of mutant phenotypes and pathogenic potential. This study may lead to better understanding of var. gattii pathogenicity by providing (a) a genetic map of genes comprising MATalpha locus, (b) characterization of the role of STE12alpha in biology and virulence, and (c) a framework for future genetic investigations of fungal virulence.

描述（由申请人提供）：加密环球球菌（CN）引起隐脑膜炎，一种真菌脑膜脑炎。该病原体具有遗传上不同的品种（var。grubii，var。Neoformans和var。Gattii）和交配类型（Matalpha和Matalpha）。这些品种在正常和免疫功能低下的个体中引起不同的宿主反应。这些致病性差异的基础机制尚不清楚。 CN VAR。 Grubii是全球隐球菌病的最常见原因。 var。在欧洲，Neoformans感染已被认可。由于VAR引起的原发性和机会性感染。直到最近来自澳大利亚，东南亚和南美的Gattii，北美的罕见报道。由于当前的主要VAR报告，这种流行病学发生了巨大变化。加拿大不列颠哥伦比亚省的人类和动物的Gattii爆发。目前，CN交配正在进行深入研究，以定义真菌毒力与Matalpha之间观察到的联系，并了解调节信号通路。最近，来自Var的Matalpha和Matalpha基因座。 grubii和var。对新外ing剂进行了映射，许多MAT特异性基因在真菌生物学和毒力中的作用正在深入研究。但是，这些强大的分子遗传分析尚未扩展到VAR。 Gattii，这对于更好地了解其发病机理和更有效的治疗至关重要。来自Var的新兴知识。 grubii和var。在该实验室中应用了NeoFormans，以开发基于DNA的快速测试，以识别所有品种和交配类型。对Matalpha/Alpha信息素的进一步研究揭示了多样性的特异性，不同的拷贝数和染色体位置以及交叉交配和/或杂交的潜力。当前的提案通过仅专注于VAR来建立这些调查。 gattii。我们的具体目标是：（i）包含Matalpha基因座的基因的识别，映射和系统发育研究，以及（ii）VAR的表征。 Gattii Ste12alpha cDNA，基因敲除突变体的构建以及突变表型和致病潜力的研究。这项研究可能会更好地了解VAR。通过提供（a）包含Matalpha基因座的基因的遗传图，（b）表征Ste12alpha在生物学和毒力中的作用，以及（c）真菌病毒力遗传研究的框架。