Bergstralh Dan T, Dawney Nicole S, St Johnston Daniel
Department of Biology, University of Rochester, Rochester, NY 14627, USA
Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Development. 2017 Apr 1;144(7):1137-1145. doi: 10.1242/dev.140764.
The direction in which a cell divides is determined by the orientation of its mitotic spindle at metaphase. Spindle orientation is therefore important for a wide range of developmental processes, ranging from germline stem cell division to epithelial tissue homeostasis and regeneration. In multiple cell types in multiple animals, spindle orientation is controlled by a conserved biological machine that mediates a pulling force on astral microtubules. Restricting the localization of this machine to only specific regions of the cortex can thus determine how the mitotic spindle is oriented. As we review here, recent findings based on studies in tunicate, worm, fly and vertebrate cells have revealed that the mechanisms for mediating this restriction are surprisingly diverse.
细胞分裂的方向由其在中期的有丝分裂纺锤体的方向决定。因此，纺锤体方向对于从生殖系干细胞分裂到上皮组织稳态和再生等广泛的发育过程都很重要。在多种动物的多种细胞类型中，纺锤体方向由一种保守的生物机制控制，该机制介导对星体微管的拉力。因此，将这种机制的定位限制在皮质的特定区域可以决定有丝分裂纺锤体的方向。正如我们在此所综述的，基于对被囊动物、蠕虫、果蝇和脊椎动物细胞的研究的最新发现表明，介导这种限制的机制惊人地多样。
