Ubiquitin editing enzyme UCH L1 and microtubule dynamics: implication in mitosis.
Ubiquitin editing enzyme UCH L1 and microtubule dynamics: implication in mitosis.
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泛素编辑酶UCH L1和微管动力学：有丝分裂的影响。
DOI：
10.4161/cc.9.5.10934
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发表时间：
2010-03-01
期刊：
影响因子：
--
通讯作者：
Shackelford J
中科院分区：
文献类型：
--
作者：
Bheda A;Gullapalli A;Caplow M;Pagano JS;Shackelford J
微管是细胞骨架的重要组成部分，并参与细胞反应的许多方面，包括细胞分裂，迁移和细胞内信号转导。在其他因素中，翻译后修饰在微管动力学的调节中起重要作用。在这里，我们证明了泛素编辑酶UCH L1，其丰富的表达通常仅限于脑组织，也是各种转化细胞中微管网络的一部分。此外，在有丝分裂过程中，内源性UCH L1的表达和紧密相关的有丝分裂纺锤体通过M期的所有阶段，这表明UCH L1参与调控微管动力学。事实上，在体外微管蛋白聚合反应中加入重组UCH L1对微管形成具有抑制作用。出乎意料的是，聚合后的微管蛋白组分的蛋白质印迹分析显示存在与微管相关的UCH L1的特异性1050 kDa条带（而不是正常的1025 kDa），但不与游离微管蛋白相关。此外，我们发现，沿着25 kDa UCH L1，内源性高分子量UCH L1复合物存在于细胞中，并且在有丝分裂期间，50 kDa UCH L1复合物的水平在细胞中增加。最后，我们提供的证据表明，泛素化参与微管蛋白聚合：在体外聚合过程中存在的泛素本身抑制微管的形成，并增强了UCH L1的抑制作用。UCH L1的抑制作用与微管组分的泛素化增加相关。由于除了是一种去泛素化酶，UCH L1作为二聚体也显示出泛素连接酶的活性，我们讨论的可能性，观察到的50 kDa的UCH L1是一个二聚体，防止微管形成通过微管蛋白和/或微管相关蛋白的泛素化。
Microtubules are essential components of the cytoskeleton and are involved in many aspects of cell responses including cell division, migration, and intracellular signal transduction. Among other factors, post-translational modifications play a significant role in the regulation of microtubule dynamics. Here, we demonstrate that the ubiquitin-editing enzyme UCH L1, abundant expression of which is normally restricted to brain tissue, is also a part of the microtubule network in a variety of transformed cells. Moreover, during mitosis, endogenous UCH L1 is expressed and tightly associated with the mitotic spindle through all stages of M phase, suggesting that UCH L1 is involved in regulation of microtubule dynamics. Indeed, addition of recombinant UCH L1 to the reaction of tubulin polymerization in vitro had an inhibitory effect on microtubule formation. Unexpectedly, western blot analysis of tubulin fractions after polymerization revealed the presence of a specific ∼50 kDa band of UCH L1 (not the normal ∼25 kDa) in association with microtubules, but not with free tubulin. In addition, we show that along with 25 kDa UCH L1, endogenous high molecular weight UCH L1 complexes exist in cells, and that levels of 50 kDa UCH L1 complexes are increasing in cells during mitosis. Finally, we provide evidence that ubiquitination is involved in tubulin polymerization: the presence of ubiquitin during polymerization in vitro by itself inhibited microtubule formation and enhanced the inhibitory effect of added UCH L1. the inhibitory effects of UCH L1 correlate with an increase in ubiquitination of microtubule components. Since besides being a deubiquitinating enzyme, UCH L1 as a dimer has also been shown to exhibit ubiquitin ligase activity, we discuss the possibility that the ∼50 kDa UCH L1 observed is a dimer which prevents microtubule formation through ubiquitination of tubulins and/or microtubule-associated proteins.
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影响因子：
8.4
作者：
Loeffler-Ragg, J;Skvortsov, S;Zwierzina, H
通讯作者：
Zwierzina, H
DOI：
10.1083/jcb.200903066
发表时间：
2009-08-24
期刊：
The Journal of cell biology
影响因子：
--
作者：
Huang K;Diener DR;Rosenbaum JL
通讯作者：
Rosenbaum JL
影响因子：
5.3
作者：
Long, EM;Long, MA;Gray, DA
通讯作者：
Gray, DA
影响因子：
64.5
作者：
Liu, YC;Fallon, L;Lansbury, PT
通讯作者：
Lansbury, PT
DOI：
10.5851/kosfa.2008.28.1.27
发表时间：
2008-03-01
影响因子：
--
作者：
Kim, Y. H.;Yoo, J. S.;Kim, I. H.
通讯作者：
Kim, I. H.