Cullen C F, Deák P, Glover D M, Ohkura H
Institute of Cell and Molecular Biology, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom.
J Cell Biol. 1999 Sep 6;146(5):1005-18. doi: 10.1083/jcb.146.5.1005.
We describe a new Drosophila gene, mini spindles (msps) identified in a cytological screen for mitotic mutant. Mutation in msps disrupts the structural integrity of the mitotic spindle, resulting in the formation of one or more small additional spindles in diploid cells. Nucleation of microtubules from centrosomes, metaphase alignment of chromosomes, or the focusing of spindle poles appears much less affected. The msps gene encodes a 227-kD protein with high similarity to the vertebrate microtubule-associated proteins (MAPs), human TOGp and Xenopus XMAP215, and with limited similarity to the Dis1 and STU2 proteins from fission yeast and budding yeast. Consistent with their sequence similarity, Msps protein also associates with microtubules in vitro. In the embryonic division cycles, Msps protein localizes to centrosomal regions at all mitotic stages, and spreads over the spindles during metaphase and anaphase. The absence of centrosomal staining in interphase of the cellularized embryos suggests that the interactions between Msps protein and microtubules or centrosomes may be regulated during the cell cycle.
我们描述了一个新的果蝇基因——小纺锤体（msps），它是在一项针对有丝分裂突变体的细胞学筛选中被鉴定出来的。msps基因突变会破坏有丝分裂纺锤体的结构完整性，导致二倍体细胞中形成一个或多个额外的小纺锤体。来自中心体的微管成核、染色体的中期排列或纺锤体极的聚焦似乎受影响较小。msps基因编码一种227-kD的蛋白质，它与脊椎动物微管相关蛋白（MAPs）、人类TOGp和非洲爪蟾XMAP215高度相似，与裂殖酵母和芽殖酵母的Dis1和STU2蛋白有有限的相似性。与其序列相似性一致，Msps蛋白在体外也与微管相关。在胚胎分裂周期中，Msps蛋白在所有有丝分裂阶段都定位于中心体区域，并在中期和后期扩散到纺锤体上。在细胞化胚胎的间期没有中心体染色，这表明Msps蛋白与微管或中心体之间的相互作用可能在细胞周期中受到调控。
