Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA.
J Cell Biol. 2013 Jan 21;200(2):131-40. doi: 10.1083/jcb.201210007.
Accurate positioning of spindles is essential for asymmetric mitotic and meiotic cell divisions that are crucial for animal development and oocyte maturation, respectively. The predominant model for spindle positioning, termed "cortical pulling," involves attachment of the microtubule-based motor cytoplasmic dynein to the cortex, where it exerts a pulling force on microtubules that extend from the spindle poles to the cell cortex, thereby displacing the spindle. Recent studies have addressed important details of the cortical pulling mechanism and have revealed alternative mechanisms that may be used when microtubules do not extend from the spindle to the cortex.
纺锤体的准确定位对于动物发育和卵母细胞成熟所分别必需的不对称有丝分裂和减数分裂至关重要。用于纺锤体定位的主要模型称为“皮质牵拉”，涉及基于微管的运动细胞质动力蛋白与皮质的附着，在该处，它对从纺锤体极延伸到细胞皮质的微管施加拉力，从而使纺锤体移位。最近的研究解决了皮质牵拉机制的重要细节，并揭示了当微管不从纺锤体延伸到皮质时可能使用的替代机制。
