TRPML1 Protein Functions in Lysosome Biogenesis

TRPML1 蛋白在溶酶体生物发生中的功能

• 批准号: 1052166
• 负责人: Hanna Fares
• 金额: $ 43.71万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1052166&HistoricalAwards=false
• 关键词: TRPML1; Protein; Functions; Lysosome; Biogenesis

Intellectual merit. The aim of this project is to decipher mechanisms of lysosome biogenesis. Lysosomes are the main membrane-bound, degradative organelles of eukaryotic cells. In addition to degrading molecules taken up from the extracellular medium by endocytosis, lysosomes regulate multiple essential cellular processes, including normal turnover of components of cellular organelles, degradation of cellular material in response to starvation, degradation of signaling receptors as needed to regulate developmental pathways, fusion with the plasma membrane to initiate wound healing, and participation in some cell death pathways. Given this central importance of lysosomes, it is striking that little is known about basic principles of how lysosomes are formed. Studies have shown that lysosomal biogenesis proceeds by budding of a membrane extension from the endosomal compartment followed by vesicle scission to release a newly formed lysosome. Preliminary studies for this project identified the TRPML1 protein as an initial regulator of lysosome biogenesis. The studies showed that this protein, which has also been shown to be a channel protein that is dysfunctional in lysosomal storage disorders, is required for the membrane extension and scission steps. Based on protein interactor analyses and drug inhibition studies, a model of lysosome biogenesis was proposed in which TRPML1 recruits proteins following budding that initiate actin fiber formation at the sites of lysosome biogenesis. TRPML1 channel activity then promotes actin polymerization/force generation that leads to membrane extension and eventually scission. This project tests this model and will establish the first detailed mechanistic view of lysosomal biogenesis.Broader impacts. These studies will transform current views of membrane transport by establishing the first molecular model of lysosomal biogenesis that likely will lead to new understanding of both lysosomal and other transport processes. In addition, this research program will rely heavily on direct undergraduate participation to conduct the experiments for which the PI will provide a mentorship role. This faculty member will continue training efforts, which in the past nine years have involved twenty undergraduate students, including thirteen from under-represented groups. As in the past, the majority of these students will likely continue in graduate programs, will present the results of this research at conferences, and will be co-authors on peer-reviewed publications. The research program will be used as a platform for the scientific development of the next generations of scientists and health professionals from this institution.

智力优点。 该项目的目的是破译溶酶体生物发生的机制。 溶酶体是真核细胞的主要膜结合，降解细胞器。 除了通过内吞作用从细胞外培养基中取得的降解分子外，溶酶体还调节多个必需的细胞过程，包括细胞器细胞器成分的正常周转，细胞材料对饥饿的响应降解，对饥饿的响应，对信号受体的降解，以调节发育途径，以使某些细胞受到质膜的融合，从而调节型号的发育途径。 鉴于溶酶体的这一核心重要性，令人惊讶的是，关于如何形成溶酶体的基本原理知之甚少。 研究表明，溶酶体生物发生是通过内体室的膜延伸而萌芽的，然后进行囊泡分裂以释放新形成的溶酶体。 该项目的初步研究将TRPML1蛋白确定为溶酶体生物发生的初始调节剂。研究表明，这种蛋白质也被证明是一种通道蛋白，在溶酶体储存障碍中功能障碍，是膜延伸和分裂步骤所必需的。 基于蛋白质相互作用的分析和药物抑制研究，提出了一种溶酶体生物发生模型，其中TRPML1在萌芽后募集蛋白质，该蛋白质在萌芽的蛋白质中启动肌动蛋白纤维形成在溶酶体生物发生部位。 然后，TRPML1通道活性促进肌动蛋白聚合/力的产生，从而导致膜延伸并最终导致分裂。 该项目测试了该模型，并将建立溶酶体生物发生的第一个详细机械观点。 这些研究将通过建立第一个溶酶体生物发生的分子模型来改变膜转运的当前观点，这可能会导致对溶酶体和其他转运过程的新理解。 此外，该研究计划将在很大程度上依靠直接的本科参与来进行PI提供指导角色的实验。 这位教职员工将继续培训工作，在过去的九年中，这涉及二十名本科生，包括来自代表性不足的团体的13名。 与过去一样，这些学生中的大多数可能会继续进行研究生课程，将在会议上介绍这项研究的结果，并将成为同行评审的出版物的合着者。 该研究计划将被用作该机构下一代科学家和卫生专业人员的科学发展的平台。