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）：申请人目前是经验丰富的博士后同胞，过渡为独立研究员的角色。直接的职业目标是完成当前的研究并获得桥接资源，以促进建立学术研究职位。 K22奖和职业发展计划将与开发国际认可的实验室调查真菌的长期职业目标联系起来，从而导致人类疾病或过敏。 光影响真菌种类的许多特性，例如调节性或无性孢子形成，色素产生，光质主义和设定昼夜节律。 BWC1和BWC2基因编码假定的光感受器和相互作用的转录因子，通过光控制交配，对紫外线辐射的耐受性以及人类致病真菌Neoformans的毒力。但是，目前尚不清楚哪些基因通过BWC1-BWC2调节。通过这项研究，他们的识别将为控制真菌传染病提供指导。 目的1是使用整个基因组微阵列分析转录的基因，比较在恒定黑暗中生长或用光脉冲处理的野生型应变。 AIM 2是证明光调节基因的启动子通过凝胶迁移率转移测定法与BWC1-BWC2物理相互作用。初步研究揭示了30个光调节的基因。一种这样的基因编码铁螯合酶，它催化了原源性IX的血红素生物合成的最后一步。血红素是许多蛋白质中必不可少的共同因素，而卟啉具有高度光反应性。 AIM 3将检验以下假设：铁螯合酶活性是介导新生梭菌对光和毒力敏感性的主要因素。将构建具有铁胆管酶表达水平改变的菌株，并在巨噬细胞系模型中测试了其表型，以测试其交配，紫外线敏感性和毒力。 这项研究的相关性是，它将能够发现新基因，使真菌能够对人类有力并在自然界中传播。预计该信息将提供策略，以最大程度地减少对真菌接种物的暴露，以减少引起过敏的孢子的初始感染或暴露于孢子，并使设计策略使用光作为针对真菌疾病的疗法。