Illuminating Heme Trafficking and Signaling Pathways in Health and Disease

项目摘要 这项提案的长期目标是阐明介导血红素的分子和机制 在健康和疾病中的贩运和信号传递。血红素是一种必需的但具有潜在细胞毒性的金属辅因子， 信号分子和铁的营养来源。所有血红素依赖过程都要求血红素安全地 从摄取或合成位点转运和运输到血红素依赖性或调节蛋白质， 整个细胞。然而，介导血红素动员的分子和机制， 人们对贩运和信号传递知之甚少。此外，血红素运输的时空动力学是 未知这在很大程度上是由于缺乏工具可用于图像不稳定血红素池相关 生物分布Reddi实验室最近克服了这些技术障碍， 编码比率荧光血红素传感器和表征血红素的血蛋白质组学方法 贩运和信号动态。这项提案将集中在整合分子遗传学，生物化学， 生物物理学、细胞生物学和化学生物学方法来阐明：血红素运输和 贩运; B.基于血红素的信号转导;和c.不同真核生物模型中血红素获得 细胞系，例如酿酒酵母和哺乳动物细胞系，以及病原体，例如分枝杆菌 结核病和白色念珠菌。为了探测细胞内血红素运输，基因编码的血红素传感器 将用于基因缺失和过表达筛选，以确定血红素分布的新途径， 贩卖人口为了探测血红素信号传导，将部署血蛋白质组学方法和血红素螯合剂， 确定血红素信号是如何启动，传输和整合，以控制新陈代谢和生理。到 通过人类病原体、血红素传感器和血蛋白质组学方法获得探针血红素， 整合以确定结核分枝杆菌摄取和利用血红素的机制， 白念珠菌总之，拟议的研究将全面解决血红素的机制， 在与健康和疾病相关的各种情况下，

PROJECT SUMMARY The long-term objectives of this proposal are to elucidate the molecules and mechanisms that mediate heme trafficking and signaling in health and disease. Heme is an essential but potentially cytotoxic metallocofactor, signaling molecule, and nutritional source of iron. All heme-dependent processes require that heme is safely transported and trafficked from sites of uptake or synthesis to heme dependent or regulated proteins located throughout the cell. However, the molecules and mechanisms that mediate the mobilization of heme for trafficking and signaling are poorly understood. Further, the spatio-temporal dynamics of heme trafficking are unknown. This is in large part due to the lack of tools available to image labile heme pools relevant to it biodistribution. The Reddi lab has recently overcome these technological barriers by generating genetically encoded ratiometric fluorescent heme sensors and hemoproteomics approaches to characterize heme trafficking and signaling dynamics. This proposal will focus on integrating molecular genetic, biochemical, biophysical, cell biological, and chemical biology approaches towards elucidating: a. heme transport and trafficking; b. heme-based signal transduction; and c. heme acquisition across a variety of model eukaryotic cell lines, e.g. Saccharomyces cerevisiae and mammalian cell lines, and pathogens, e.g. Mycobacterium tuberculosis and Candida albicans. To probe intracellular heme trafficking, genetically encoded heme sensors will be used in gene deletion and over-expression screens to identify novel pathways for heme distribution and trafficking. To probe heme signaling, hemoproteomics approaches and heme chelators will be deployed to identify how heme signals are initiated, transmitted, and integrated to control metabolism and physiology. To probe heme acquisition by human pathogens, heme sensors and hemoproteomics approaches will be integrated to identify the mechanisms of heme uptake and utilization by Mycobacterium tuberculosis and Candida albicans. Altogether, the proposed research will comprehensively address the mechanisms of heme trafficking and signaling in various contexts relevant to health and disease.