PDZ interactions regulate rapid turnover of the scaffolding protein EBP50 in microvilli.
PDZ interactions regulate rapid turnover of the scaffolding protein EBP50 in microvilli.
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DOI：
10.1083/jcb.201204008
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发表时间：
2012-07-23
期刊：
影响因子：
--
通讯作者：
Bretscher A
中科院分区：
文献类型：
--
作者：
Garbett D;Bretscher A
相对稳定的微绒毛组件连接在体内的支架蛋白EBP 50，尽管其令人惊讶的高周转率。含有PDZ（突触后密度95/盘大/闭锁小带-1）结构域的支架蛋白被认为在大分子复合物的组分之间提供相对稳定的连接，并且在某些情况下桥接到肌动蛋白细胞骨架。微绒毛支架蛋白EBP 50（ERM-binding phosphoprotein of 50 kD）由两个PDZ结构域和一个ezrin结合位点组成，保留微绒毛中的特异性蛋白，是微绒毛生物发生所必需的。我们的微绒毛蛋白在体内的动力学分析表明，埃兹蛋白和微绒毛膜蛋白的动力学与肌动蛋白微铣削和微绒毛寿命一致。然而，EBP 50是高度动态的，在几秒钟内翻转。EBP 50营业额减少的突变，其PDZ结构域和蛋白激酶C磷酸化增强。使用一种新的体外光活化荧光测定，EBP 50-埃兹蛋白相互作用显示出具有缓慢的解离速率，其通过加入细胞提取物至接近体内水平以PDZ调节的方式显著增强。因此，相对稳定的微绒毛组件的连接可以介导的令人惊讶的动态EBP 50，这一发现可能有其他支架蛋白的重要分支。
Relatively stable microvillar components are linked in vivo by the scaffolding protein EBP50 in spite of its surprisingly high turnover rate. Scaffolding proteins containing PDZ (postsynaptic density 95/discs large/zonula occludens-1) domains are believed to provide relatively stable linkages between components of macromolecular complexes and in some cases to bridge to the actin cytoskeleton. The microvillar scaffolding protein EBP50 (ERM-binding phosphoprotein of 50 kD), consisting of two PDZ domains and an ezrin-binding site, retains specific proteins in microvilli and is necessary for microvillar biogenesis. Our analysis of the dynamics of microvillar proteins in vivo indicated that ezrin and microvillar membrane proteins had dynamics consistent with actin treadmilling and microvillar lifetimes. However, EBP50 was highly dynamic, turning over within seconds. EBP50 turnover was reduced by mutations that inactivate its PDZ domains and was enhanced by protein kinase C phosphorylation. Using a novel in vitro photoactivation fluorescence assay, the EBP50–ezrin interaction was shown to have a slow off-rate that was dramatically enhanced in a PDZ-regulated manner by addition of cell extract to near in vivo levels. Thus, the linking of relatively stable microvillar components can be mediated by surprisingly dynamic EBP50, a finding that may have important ramifications for other scaffolding proteins.
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影响因子：
64.5
作者：
Drees, F;Pokutta, S;Weis, WI
通讯作者：
Weis, WI
DOI：
10.1083/jcb.200604046
发表时间：
2006-12-04
期刊：
The Journal of cell biology
影响因子：
--
作者：
Hanono A;Garbett D;Reczek D;Chambers DN;Bretscher A
通讯作者：
Bretscher A
影响因子：
3.3
作者：
LaLonde DP;Garbett D;Bretscher A
通讯作者：
Bretscher A
影响因子：
12.4
作者：
Chen, J-Y;Lin, Y-Y;Jou, T-S
通讯作者：
Jou, T-S
影响因子：
3.4
作者：
Tyska, MJ;Mooseker, MS
通讯作者：
Mooseker, MS