期刊
NEUROPHARMACOLOGY
卷 47, 期 5, 页码 734-745出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.neuropharm.2004.07.022
关键词
alpha-actinin; dendritic spine; FRAP; time lapse imaging; actin cytoskeleton; filopodia; synapse
Excitatory synapses are located on actin-rich protrusions known as dendritic spines. alpha-Actinin is an actin binding protein enriched in the postsynaptic density (PSD) of excitatory synapses. Because it also binds to NMDA receptors and other PSD components, alpha-actinin has been proposed to link NMDA receptors and the PSD to the underlying actin cytoskeleton of the dendritic spine. Although alpha-actinin has been implicated in modulation of NMDA receptor activity, the cell biological function of alpha-actinin in neurons is unknown. We report here that alpha-actinin is concentrated in spines. Both the actin binding domain and the spectrin repeat region (which interacts with NMDA receptors) of alpha-actinin2 are required for spine targeting. In live imaging experiments, Venus-tagged alpha-actinin2 in dendritic spines showed faster turnover than PSD-95, as determined by fluorescent recovery after photobleaching (FRAP), and individual spines often showed marked fluctuations in a-actinin content over a time-scale of minutes. Overexpression of alpha-actinin2 increased the length and density of dendritic protrusions in cultured hippocampal neurons, an effect that requires the actin binding domain and the spectrin repeats of alpha-actinin. These results suggest that ot-actinin regulates spine morphology and density. (C) 2004 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据