Coquelle Frédéric M, Caspi Michal, Cordelières Fabrice P, Dompierre Jim P, Dujardin Denis L, Koifman Cynthia, Martin Patrick, Hoogenraad Casper C, Akhmanova Anna, Galjart Niels, De Mey Jan R, Reiner Orly
Institut Curie, Section de Recherche, CNRS-UMR 146, Centre Universitaire d'Orsay, 91405 Orsay Cedex, France.
Mol Cell Biol. 2002 May;22(9):3089-102. doi: 10.1128/MCB.22.9.3089-3102.2002.
CLIP-170 is a plus-end tracking protein which may act as an anticatastrophe factor. It has been proposed to mediate the association of dynein/dynactin to microtubule (MT) plus ends, and it also binds to kinetochores in a dynein/dynactin-dependent fashion, both via its C-terminal domain. This domain contains two zinc finger motifs (proximal and distal), which are hypothesized to mediate protein-protein interactions. LIS1, a protein implicated in brain development, acts in several processes mediated by the dynein/dynactin pathway by interacting with dynein and other proteins. Here we demonstrate colocalization and direct interaction between CLIP-170 and LIS1. In mammalian cells, LIS1 recruitment to kinetochores is dynein/dynactin dependent, and recruitment there of CLIP-170 is dependent on its site of binding to LIS1, located in the distal zinc finger motif. Overexpression of CLIP-170 results in a zinc finger-dependent localization of a phospho-LIS1 isoform and dynactin to MT bundles, raising the possibility that CLIP-170 and LIS1 regulate dynein/dynactin binding to MTs. This work suggests that LIS1 is a regulated adapter between CLIP-170 and cytoplasmic dynein at sites involved in cargo-MT loading, and/or in the control of MT dynamics.
CLIP-170是一种正向末端追踪蛋白，可能作为一种抗灾变因子发挥作用。有人提出它可介导动力蛋白/动力蛋白激活蛋白与微管（MT）正向末端的结合，并且它还以动力蛋白/动力蛋白激活蛋白依赖的方式通过其C末端结构域与动粒结合。该结构域包含两个锌指基序（近端和远端），据推测它们介导蛋白质-蛋白质相互作用。LIS1是一种与大脑发育有关的蛋白，通过与动力蛋白及其他蛋白相互作用，在由动力蛋白/动力蛋白激活蛋白途径介导的多个过程中发挥作用。在此我们证明了CLIP-170与LIS1的共定位及直接相互作用。在哺乳动物细胞中，LIS1募集到动粒是动力蛋白/动力蛋白激活蛋白依赖的，而CLIP-170在那里的募集则依赖于其与位于远端锌指基序中的LIS1的结合位点。CLIP-170的过表达导致一种磷酸化LIS1亚型和动力蛋白激活蛋白以锌指依赖的方式定位于MT束，这增加了CLIP-170和LIS1调节动力蛋白/动力蛋白激活蛋白与MTs结合的可能性。这项工作表明，LIS1是CLIP-170与细胞质动力蛋白之间在涉及货物-MT装载和/或MT动力学控制的位点上的一种受调控的衔接蛋白。
