Gachet Y, Tournier S, Millar J B, Hyams J S
Department of Biology, University College London, Gower Street, London WC1E 6B, UK.
Nature. 2001 Jul 19;412(6844):352-5. doi: 10.1038/35085604.
The accurate segregation of chromosomes at mitosis depends on a correctly assembled bipolar spindle that exerts balanced forces on each sister chromatid. The integrity of mitotic chromosome segregation is ensured by the spindle assembly checkpoint (SAC) that delays mitosis in response to defective spindle organisation or failure of chromosome attachment. Here we describe a distinct mitotic checkpoint in the fission yeast, Schizosaccharomyces pombe, that monitors the integrity of the actin cytoskeleton and delays sister chromatid separation, spindle elongation and cytokinesis until spindle poles have been properly oriented. This mitotic delay is imposed by a stress-activated mitogen-activated protein (MAP) kinase pathway but is independent of the anaphase-promoting complex (APC).
有丝分裂时染色体的准确分离依赖于正确组装的双极纺锤体，该纺锤体对每个姐妹染色单体施加平衡力。纺锤体组装检查点（SAC）确保有丝分裂染色体分离的完整性，它会在纺锤体组织缺陷或染色体附着失败时延迟有丝分裂。在这里，我们描述了裂殖酵母中的一种独特的有丝分裂检查点，该检查点监测肌动蛋白细胞骨架的完整性，并延迟姐妹染色单体分离、纺锤体延长和胞质分裂，直到纺锤体极正确定向。这种有丝分裂延迟是由应激激活的丝裂原活化蛋白（MAP）激酶途径引起的，但与后期促进复合物（APC）无关。
