Shao Dongmin, Segal Anthony W, Dekker Lodewijk V
Department of Medicine, University College London, The Rayne Institute, 5 University Street, London WC1E 6JJ, UK.
FEBS Lett. 2003 Aug 28;550(1-3):101-6. doi: 10.1016/s0014-5793(03)00845-7.
We have investigated the contribution of lipid rafts to activation of the NADPH oxidase enzyme system in neutrophils. Membrane-bound NADPH oxidase subunits are present in the lipid raft compartment of neutrophils. Cytosolic NADPH oxidase components are mainly absent from but are recruited to rafts upon Fcgamma receptor activation. In parallel, protein kinase C isotypes are recruited to the rafts. Kinetic analysis of NADPH oxidase activation revealed that rafts determine the onset but not the maximal rate of enzyme activity. Thus lipid rafts serve to physically juxtapose the NADPH oxidase effector, protein kinase C and Fcgamma receptor, resulting in efficient coupling.
我们研究了脂筏对中性粒细胞中NADPH氧化酶系统激活的作用。膜结合的NADPH氧化酶亚基存在于中性粒细胞的脂筏区室中。胞质NADPH氧化酶成分主要不存在于脂筏中，但在Fcγ受体激活后会被招募到脂筏。同时，蛋白激酶C同工型也被招募到脂筏。对NADPH氧化酶激活的动力学分析表明，脂筏决定了酶活性的起始，但不决定其最大速率。因此，脂筏有助于将NADPH氧化酶效应物、蛋白激酶C和Fcγ受体物理并列，从而实现有效偶联。
