Lysosomal Membrane Proteins and their Roles in Phagosome Maturation

溶酶体膜蛋白及其在吞噬体成熟中的作用

• 批准号: 198129374
• 负责人: Professor Dr. Albert Haas
• 金额: --
• 依托单位: Institut für Zellbiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/198129374?language=en
• 关键词: Lysosomal; Membrane; Proteins; their; Roles

Invaded microorganisms or extracellular particular debris are recognized by specific immune cells, in particular macrophages. These remove the particles by uptake into a membrane-bound phagosome which will mature into a phagolysosome. Some lysosomal hydrolases, proton-pumping ATPase and lysosomal membrane proteins play critical roles in killing and digestion of ingested microorganisms in a phagolysosome, as has been shown for some of them using transgenic mouse models and cells derived from them. This application proposes to probe processing of phagosomes containing model particles or bacterial intracellular pathogens in macrophages, granulocytes and embryonic fibroblasts with deletion in the genes for the abundant lysosome membrane proteins LAMP-1, LAMP-2, LIMP-2 and LIMP-1/CD63, in LAMP-1 as well as LAMP-2, or in transmembrane subunits of the protonpumping vacuolar ATPase which is crucial for function of the endocytic pathway. Regular and diverted phagosome maturation will be followed microscopically and biochemically in cells infected with harmless microorganisms (Escherichia coli safety strains, baker’s yeast) or a pathogenic bacterium (Listeria monocytogenes) or fed with inert latex bead particles. In addition, the effects of host cell mutation on intra-host cell multiplication or killing will be tested. The results forseen will help to molecularly understand if and how major membrane proteins of late endosomes and lysosomes orchestrate fusion between these late endocytic compartments and different types of phagosomes and how they contribute to pathogen killing.

入侵的微生物或细胞外的特殊碎片被特定的免疫细胞，特别是巨噬细胞识别。它们通过被膜结合的吞噬体吸收来去除颗粒，吞噬体将成熟为吞噬体。一些溶酶体水解酶，质子泵送atp酶和溶酶体膜蛋白在吞噬溶酶体中杀死和消化摄入的微生物中起着关键作用，其中一些已经通过转基因小鼠模型和来源于它们的细胞得到证实。该申请旨在探讨巨噬细胞、粒细胞和胚胎成纤维细胞中含有模型颗粒或细菌胞内病原体的吞噬体在大量溶酶体膜蛋白LAMP-1、LAMP-2、LIMP-2和LIMP-1/CD63基因缺失、LAMP-1和LAMP-2基因缺失或对内吞途径功能至关重要的质子泵空泡atp酶跨膜亚基缺失的加工过程。将在感染无害微生物（大肠杆菌安全菌株、面包酵母）或致病菌（单核增生李斯特菌）或用惰性乳胶珠颗粒喂养的细胞中，用显微镜和生化方法跟踪常规和转移的吞噬体成熟。此外，还将测试宿主细胞突变对宿主内细胞增殖或杀伤的影响。所预见的结果将有助于从分子上理解晚期内吞体和溶酶体的主要膜蛋白是否以及如何协调这些晚期内吞室与不同类型吞噬体之间的融合，以及它们如何促进病原体的杀伤。