The Caenorhabditis elegans Aurora B kinase AIR-2 phosphorylates and is required for the localization of a BimC kinesin to meiotic and mitotic spindles
The Caenorhabditis elegans Aurora B kinase AIR-2 phosphorylates and is required for the localization of a BimC kinesin to meiotic and mitotic spindles
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DOI：
10.1091/mbc.e04-08-0682
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发表时间：
2005-02-01
影响因子：
3.3
通讯作者：
Schumacher, JM
中科院分区：
文献类型：
--
作者：
Bishop, JD;Han, ZB;Schumacher, JM
BimC驱动蛋白是多种生物体中有丝分裂纺锤体组装所必需的。这些蛋白质定位于中心体、纺锤体微管和纺锤体中间区。我们以前已经表明，秀丽隐杆线虫极光B激酶AIR-2是必需的本地化的ZEN-4驱动蛋白质的中区微管。为了确定BimC驱动蛋白与纺锤体微管的结合是否也依赖于AIR-2，我们检测了BMK-1的表达模式。线虫BimC驱动蛋白，在野生型和AIR-2缺陷型胚胎。BMK-1在两性生殖腺中高度表达，并定位于新受精胚胎的减数分裂纺锤体微管。在有丝分裂胚胎中，BMK-1从前期到后期与纺锤体微管相关，并在后期和末期集中在纺锤体中间区。在缺乏AIR-2的情况下，BMK-1在减数分裂和有丝分裂纺锤体上的定位大大减少。这不是ZEN-4定位丢失的结果，因为BMK-1适当地定位在ZEN-4缺陷的胚胎中。此外，AIR-2和BMK-1直接相互作用，并且BMK-1的C-末端尾部结构域在体外被AIR-2特异性磷酸化。与我们以前的数据一起，这些结果表明，极光B激酶的至少一个功能是招募纺锤体相关的马达蛋白到它们的作用位点。
BimC kinesins are required for mitotic spindle assembly in a variety of organisms. These proteins are localized to centrosomes, spindle microtubules, and the spindle midzone. We have previously shown that the Caenorhabditis elegans Aurora B kinase AIR-2 is required for the localization of the ZEN-4 kinesin protein to midzone microtubules. To determine whether the association of BimC kinesins with spindle microtubules is also dependent on AIR-2, we examined the expression pattern of BMK-1, a C. elegans BimC kinesin, in wild-type and AIR-2-deficient embryos. BMK-1 is highly expressed in the hermaphrodite gonad and is localized to meiotic spindle microtubules in the newly fertilized embryo. In mitotic embryos, BMK-1 is associated with spindle microtubules from prophase through anaphase and is concentrated at the spindle midzone during anaphase and telophase. In the absence of AIR-2, BMK-1 localization to meiotic and mitotic spindles is greatly reduced. This is not a consequence of loss of ZEN-4 localization because BMK-1 is appropriately localized in ZEN-4-deficient embryos. Furthermore, AIR-2 and BMK-1 directly interact with one another and the C-terminal tail domain of BMK-1 is specifically phosphorylated by AIR-2 in vitro. Together with our previous data, these results suggest that at least one function of the Aurora B kinases is to recruit spindle-associated motor proteins to their sites of action.