Aurora-B regulates the cleavage furrow-specific vimentin phosphorylation in the cytokinetic process
Aurora-B regulates the cleavage furrow-specific vimentin phosphorylation in the cytokinetic process
复制标题
DOI：
10.1074/jbc.m210892200
复制
发表时间：
2003-03-07
影响因子：
4.8
通讯作者：
Inagaki, M
中科院分区：
文献类型：
--
作者：
Goto, H;Yasui, Y;Inagaki, M
Aurora-B是一种进化保守的蛋白激酶，调节包括细胞分裂在内的几个有丝分裂事件。我们之前证明了可能存在一种蛋白激酶，该蛋白激酶以裂解沟特异性方式磷酸化vimentin（最广泛表达的中间丝蛋白）上的至少Ser-72。在这里，我们发现vimentin-Ser-72磷酸化发生在aurora - b定位区域的边界，从后期到末期。Aurora-B显性阴性突变体的表达导致vimentin-Ser-72磷酸化的减少。体外分析表明，Aurora-B以2 mol磷酸/mol底物磷酸化波形蛋白30分钟，并显著抑制波形蛋白细丝的形成。我们进一步鉴定了8个Aurora-B磷酸化位点，包括蛋白上的Ser-72位点，然后构建了突变蛋白，这些位点被转化为Ala。表达这种突变的细胞在未分离的子细胞之间形成了异常长的桥状中间丝结构。然后我们确定了桥型的重要磷酸化位点。我们的研究结果表明，在细胞动力学过程中，Aurora-B调节了切割沟特异性的波形蛋白磷酸化，并控制了波形蛋白细丝的分离。
Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the cleavage furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at similar to2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the cleavage furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.