LPS REGULATION OF MACROPHAGE FUNCTION

蛋白激酶C（PKC）诱导的磷酸化是必需的， 巨噬细胞对细菌脂多糖（LPS）产生应答。的 本项目的目的是研究LPS 影响PKC依赖的信号通路，例如导致 与吞噬作用有关的细胞骨架重排，膜 交通、细胞粘附和运动性。Aderem博士的重点是 MARCKS蛋白和LPS诱导型PKC的分子特征 底物，其调节膜上的肌动蛋白结构。他将 功能性缺失鼠MARCKS缺失小鼠。在另一种方法中， 确定MARCKS在体内的作用，巨噬细胞特异性启动子 将用于产生表达突变MARCKS的转基因小鼠 巨噬细胞中的蛋白质。他将描述LPS诱导的MARCKS 通过在5'上游区域中限定调控元件来修饰启动子。的 内含子和3'非翻译区也将被分析，以确定是否存在内含子。 存在调控因素。MARCKS瞄准的机制 将通过生物物理技术分析特定膜， 表征MARCKS结合蛋白。MARCKS的作用 将定义吞噬作用、溶酶体募集和转胞吞作用 使用MARCKS突变体和修饰吞噬途径的微生物。 他将通过检测MARCKS在细胞运动中的作用， 肌动蛋白结构和动力学，钙调素，极化膜 插入，表达MARCKS突变体的不动细胞。一种新的50 kDa 在巨噬细胞吞噬作用期间诱导的蛋白质， 与吞噬体结合，也将被表征。

Protein kinase C (PKC)- induced phosphorylation is necessary for macrophages to respondfully to bacterial lipopolysaccharides (LPS). The aim of this project is to investigate the mechanism by which LPS influences PKC-dependent signalling pathways such as those leading to the cytoskeletal rearrangements associated with phagocytosis, membrane traffic, cellular adherence and motility. Dr. Aderem's focus is the molecular characterization of the MARCKS protein, and LPS-inducible PKC substrate, which regulates actin structure at the membrane. He will functionally delete the murine MARCKS null mice. In another approach to determining the role(s) of MARCKS in vivo, a macrophage-specific promoter will be used to generate transgenic mice expressing mutant MARCKS proteins in macrophages. He will characterize the LPS- inducible MARCKS promoter by defining regulatory elements in the 5' upstream region. The intron and the 3' untranslated region will also be analyzed for the presence of regulatory elements. The mechanism by which MARCKS targets to specific membranes will be analyzed by biophysical techniques, and by characterizing MARCKS binding proteins. The role of MARCKS in phagocytosis, lysosome recruitment, and transcytosis will be defined using MARCKS mutants and microbes which modify the phagocytic pathway. He will characterize the role of MARCKS in cell motility by examining actin structure and dynamics, calmodulin, and polarized membrane insertion, immotile cells expressing MARCKS mutants. A novel 50 kDa protein which is induced during phagocytosis in macrophages, and which associates with phagosomes, will also be characterized.