Andrews Catherine A, Díaz-Martínez Laura A, Giménez-Abián Juan F, Guacci Vincent, Vas Amit C, Clarke Duncan J
Department of Genetics, Cell Biology & Development, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
Cell Cycle. 2005 Nov;4(11):1555-7. doi: 10.4161/cc.4.11.2144. Epub 2005 Nov 5.
The spindle assembly checkpoint monitors biorientation of chromosomes on the metaphase spindle and inhibits the Anaphase Promoting Complex (APC) specificity factor Cdc20. If APC-Cdc20 is the sole target of the spindle checkpoint, then cells lacking APC and its targets, B-type cyclin and securin, would lack spindle checkpoint function. We tested this hypothesis in yeast cells that are APC-null. Surprisingly, we find that such yeast cells are able to activate the spindle assembly checkpoint, delaying cell cycle progression in G2/M phase. These data suggest that the spindle checkpoint has a non-APC target that can restrain anaphase onset.
纺锤体组装检验点监测中期纺锤体上染色体的双定向，并抑制后期促进复合物（APC）特异性因子Cdc20。如果APC-Cdc20是纺锤体检验点的唯一靶点，那么缺乏APC及其靶点（B型细胞周期蛋白和分离酶）的细胞将缺乏纺锤体检验点功能。我们在APC缺失的酵母细胞中验证了这一假设。令人惊讶的是，我们发现这类酵母细胞能够激活纺锤体组装检验点，使细胞周期进程在G2/M期延迟。这些数据表明，纺锤体检验点有一个非APC靶点，可抑制后期起始。
