Light-regulated genes affecting the pathogen potential of Cryptococcus neoformans

影响新型隐球菌致病潜力的光调控基因

• 批准号: 7249522
• 负责人: ALEXANDER IDNURM
• 金额: $ 16.14万
• 依托单位: UNIVERSITY OF MISSOURI KANSAS CITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-15 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7249522
• 关键词: Affect; Area; Cell Extracts; Cell Line; Communicable Diseases; Cryptococcus neoformans; Darkness; Development Plans; Disease; Environment; Exposure to; Gene Expression Regulation; Gene Proteins; Genes; Genetic Transcription; Genome; Goals; Heme; Human; Hypersensitivity; Infection; K22 Award; Laboratories; Light; Link; Mediating; Microarray Analysis; Modeling; Nature; Northern Blotting; Partner in relationship; Phenotype; Photobiology; Photoreceptors; Phototropism; Physiologic pulse; Pigments; Porphyrins; Positioning Attribute; Postdoctoral Fellow; Production; Property; Proteins; Pulse taking; Recombinants; Reproduction spores; Research; Research Personnel; Research Proposals; Resources; Role; Signal Transduction; Testing; UV sensitive; Virulence; Virulent; asexual; career; circadian pacemaker; design; experience; ferrochelatase; fungus; gel mobility shift assay; heme biosynthesis; human disease; macrophage; member; mutant; pathogen; programs; promoter; protoporphyrin IX; transcription factor; ultraviolet irradiation; white collar 1

DESCRIPTION (provided by applicant): The applicant is currently an experienced post-doctoral fellow transitioning into a role as an independent investigator. Immediate career objectives are to complete current research and obtain bridging resources to facilitate the establishment of an academic research position. The K22 award and career development plans would link within the long-term career objectives of developing an internationally-recognized laboratory investigating fungi that cause human disease or allergy. Light influences many properties in species of fungi, such as regulating sexual or asexual sporulation, pigment production, phototropism, and setting a circadian clock. The BWC1 and BWC2 genes, encoding a putative photoreceptor and interacting transcription factor, control inhibition of mating by light, tolerance to UV irradiation, and virulence in the human pathogenic fungus Cryptococcus neoformans. However, it is unclear what genes are regulated by light via Bwc1-Bwc2. Their identification, through this research, will provide directions towards controlling fungal infectious disease. Aim 1 is to identify genes regulated by light using a whole genome microarray analysis of transcription, comparing a wild type strain grown in constant darkness or treated with a pulse of light. Aim 2 is to demonstrate that the promoters of light-regulated genes physically interact with Bwc1-Bwc2 by gel mobility shift assays. Preliminary studies have revealed 30 genes that are light-regulated. One such gene encodes ferrochelatase, which catalyzes the final step of heme biosynthesis from protoporphyrin IX. Heme is an essential co-factor in many proteins, while porphyrins are highly photoreactive. Aim 3 will test the hypothesis that ferrochelatase activity is a major factor that mediates C. neoformans sensitivity to light and virulence. Strains with altered expression levels of ferrochelatase will be constructed and their phenotypes tested for mating, UV sensitivity and virulence in a macrophage cell line model. The relevance of the research is that it will enable the discovery of new genes that enable fungi to be virulent towards humans and to spread in nature. This information is expected to provide strategies to minimize exposure to fungal inocula to reduce initial infection or exposure to spores that cause allergies, and enable the design of strategies to use light as a therapy against fungal diseases.

描述（由申请人提供）：申请人目前是一名经验丰富的博士后研究员，正在转变为独立研究员。近期的职业目标是完成当前的研究并获得过渡资源以促进学术研究职位的建立。 K22 奖项和职业发展计划将与建立一个国际认可的实验室来研究引起人类疾病或过敏的真菌的长期职业目标联系起来。 光影响真菌物种的许多特性，例如调节有性或无性孢子形成、色素产生、向光性和设置生物钟。 BWC1 和 BWC2 基因编码假定的光感受器和相互作用的转录因子，控制光交配的抑制、对紫外线照射的耐受性以及人类致病真菌新型隐球菌的毒力。然而，尚不清楚哪些基因通过 Bwc1-Bwc2 受光调节。通过这项研究，对它们的鉴定将为控制真菌传染病提供方向。 目标 1 是使用全基因组微阵列转录分析来鉴定受光调节的基因，比较在持续黑暗中生长或用光脉冲处理的野生型菌株。目标 2 是通过凝胶迁移率变动分析证明光调节基因的启动子与 Bwc1-Bwc2 发生物理相互作用。初步研究揭示了 30 个受光调节的基因。其中一个基因编码亚铁螯合酶，它催化原卟啉 IX 血红素生物合成的最后一步。血红素是许多蛋白质的重要​​辅助因子，而卟啉具有高度光反应性。目标 3 将检验以下假设：亚铁螯合酶活性是介导新型隐球菌对光和毒力敏感性的主要因素。将构建亚铁螯合酶表达水平改变的菌株，并在巨噬细胞系模型中测试其表型的交配、紫外线敏感性和毒力。 这项研究的意义在于，它将能够发现新的基因，使真菌对人类具有毒性并在自然界中传播。该信息预计将提供尽量减少接触真菌接种物的策略，以减少初始感染或接触引起过敏的孢子，并能够设计使用光作为真菌疾病治疗方法的策略。