Lam Wendy W, Peterson Erica A, Yeung Mantek, Lavoie Brigitte D
Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario, Canada.
Genes Dev. 2006 Nov 1;20(21):2973-84. doi: 10.1101/gad.1468806.
We describe a novel requirement for the condensin complex in sister chromatid cohesion in Saccharomyces cerevisiae. Strikingly, condensin-dependent cohesion can be distinguished from cohesin-based pairing by a number of criteria. First, condensin is required to maintain cohesion at several chromosomal arm sites but, in contrast to cohesin, is not required at either centromere or telomere-proximal loci. Second, condensin-dependent interlinks are established during mitosis independently of DNA replication and are reversible within a single cell cycle. Third, the loss of condensin-dependent linkages occurs without affecting cohesin levels at the separated URA3 locus. We propose that, during mitosis, robust sister chromatid cohesion along chromosome arms requires both condensinand cohesin-dependent mechanisms, which function independently of each other. We discuss the implications of our results for current models of sister chromatid cohesion.
我们描述了酿酒酵母中凝缩素复合物在姐妹染色单体黏附中的一种新功能。引人注目的是，凝缩素依赖性黏附可通过多个标准与基于黏连蛋白的配对区分开来。首先，凝缩素是维持几个染色体臂位点黏附所必需的，但与黏连蛋白不同，在着丝粒或端粒近端位点则不需要。其次，凝缩素依赖性交联在有丝分裂期间独立于DNA复制而建立，并且在单个细胞周期内是可逆的。第三，凝缩素依赖性连接的丧失发生时，不会影响分离的URA3位点处的黏连蛋白水平。我们提出，在有丝分裂期间，沿染色体臂的强大姐妹染色单体黏附需要凝缩素和黏连蛋白依赖性机制，这两种机制相互独立发挥作用。我们讨论了我们的结果对当前姐妹染色单体黏附模型的影响。
