A small C-terminal sequence of Aurora B is responsible for localization and function
A small C-terminal sequence of Aurora B is responsible for localization and function
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DOI：
10.1091/mbc.e04-06-0447
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发表时间：
2005-01-01
影响因子：
3.3
通讯作者：
Margolis, RL
中科院分区：
文献类型：
--
作者：
Scrittori, L;Skoufias, DA;Margolis, RL
Aurora B是有丝分裂所必需的一种蛋白激酶，在中期定位于内着丝粒，在后期定位于纺锤体中间区，是染色体分离和胞质分裂所必需的。Aurora A是Aurora B的一部分，定位于中心体和纺锤体微管。除了不同的N末端，Aurora B和Aurora A具有高度相似的序列。我们结合小干扰RNA（siRNA）切除极光B与过表达的截短突变体，研究极光B序列在其功能中的作用。在siRNA处理期间重新引入Aurora B恢复了其定位和功能。这允许进行功能恢复试验，以确定Aurora B靶向和功能的序列要求。使用该拯救方案，Aurora B独特序列的N-末端截短或Aurora A N-末端序列取代均不影响Aurora B定位或功能。将独特的Aurora B C-末端序列从末端残基344截短至残基333没有影响，但截短至326消除了定位和功能。残基326-333的缺失完全消除了定位，并在前中期阻断了细胞，从而确立了该序列对Aurora B功能至关重要。因此，我们的研究结果建立了一个小的序列作为极光B的独特定位和功能所必需的。
Aurora B, a protein kinase required in mitosis, localizes to inner centromeres at metaphase and the spindle midzone in anaphase and is required for proper chromosome segregation and cytokinesis. Aurora A, a paralogue of Aurora B, localizes instead to centrosomes and spindle microtubules. Except for distinct N termini, Aurora B and Aurora A have highly similar sequences. We have combined small interfering RNA (siRNA) ablation of Aurora B with overexpression of truncation mutants to investigate the role of Aurora B sequence in its function. Reintroduction of Aurora B during siRNA treatment restored its localization and function. This permitted a restoration of function test to determine the sequence requirements for Aurora B targeting and function. Using this rescue protocol, neither N-terminal truncation of Aurora B unique sequence nor substitution with Aurora A N-terminal sequence affected Aurora B localization or function. Truncation of unique Aurora B C-terminal sequence from terminal residue 344 to residue 333 was without effect, but truncation to 326 abolished localization and function. Deletion of residues 326-333 completely abolished localization and blocked cells at prometaphase, establishing this sequence as critical to Aurora B function. Our findings thus establish a small sequence as essential for the distinct localization and function of Aurora B.