Cryptococcus gatti mating 1oci; mapping and gene study

隐球菌 gatti 交配 1oci；

• 批准号: 6776373
• 负责人: VISHNU CHATURVEDI
• 金额: $ 8.08万
• 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 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6776373
• 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(申请人提供)：新生隐球菌(CN)引起隐球菌病，一种真菌性脑膜脑炎。病原菌具有遗传上不同的品种(var.Grubii，var.新形态者和变异体。Gattii)和交配型(Matpha和Matpha)。这些变种在正常和免疫受损的个体中引起不同的宿主反应。这些致病差异背后的机制还不是很清楚。CN var.格鲁比氏杆菌是世界范围内隐球菌病最常见的原因；在欧洲，新生杆菌感染已被大部分人认识到。由于var引起的原发感染和机会性感染。直到最近，澳大利亚、东南亚和南美洲都有Gattii的报道，北美的报道很少。随着目前一种主要变异体的报告，这种流行病学发生了巨大的变化。加拿大不列颠哥伦比亚省的人和动物中爆发了加蒂埃病毒。目前，CN交配正在进行深入的研究，以确定所观察到的真菌毒力与MATAlpha之间的联系，并了解调控信号通路。最近，来自var的MATAlpha和MATAlpha基因座。格鲁比和瓦尔。新生杆菌已被定位，许多MAT特异性基因正在深入研究它们在真菌生物学和毒力中的作用。然而，这些强大的分子遗传学分析尚未扩展到VaR。这将是更好地了解其发病机制和开发更有效的治疗方法所必需的。来自VaR的新兴知识。格鲁比和瓦尔。在这个实验室中，新生单胞菌被应用于开发基于DNA的快速检测，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品种特异性、不同的拷贝数和染色体位置，以及跨品种交配和/或杂交的可能性。目前的建议是在这些调查的基础上，专门关注风险价值。加蒂尔。我们的具体目标是：(I)鉴定、定位和系统发育包含MATAlpha基因座的基因，以及(Ii)var的特征。Gattii STE12Alpha基因，基因敲除突变体的构建，突变表型和致病潜力的研究。这项研究可能有助于更好地理解VaR。通过提供(A)包含Matpha基因座的基因的遗传图谱，(B)STE12pha在生物学和毒力中的作用的特征，以及(C)未来真菌毒力的遗传研究的框架，来研究Gattii的致病性。