Guacci V, Koshland D, Strunnikov A
Howard Hughes Medical Institute, Carnegie Institution of Washington, Department of Embryology, Baltimore, Maryland 21210, USA.
Cell. 1997 Oct 3;91(1):47-57. doi: 10.1016/s0092-8674(01)80008-8.
The S. cerevisiae MCD1 (mitotic chromosome determinant) gene was identified in genetic screens for genes important for chromosome structure. MCD1 is essential for viability and homologs are found from yeast to humans. Analysis of the mcd1 mutant and cell cycle-dependent expression pattern of Mcd1p suggest that this protein functions in chromosome morphogenesis from S phase through mitosis. The mcd1 mutant is defective in sister chromatid cohesion and chromosome condensation. The physical association between Mcd1p and Smc1p, one of the SMC family of chromosomal proteins, further suggests that Mcd1p functions directly on chromosomes. These data implicate Mcd1p as a nexus between cohesion and condensation. We present a model for mitotic chromosome structure that incorporates this previously unsuspected link.
酿酒酵母的MCD1(有丝分裂染色体决定因子)基因是在对染色体结构重要基因的遗传筛选中被鉴定出来的。MCD1对细胞生存力至关重要,并且从酵母到人类都能找到其同源物。对mcd1突变体以及Mcd1p的细胞周期依赖性表达模式的分析表明,该蛋白在从S期到有丝分裂的染色体形态发生过程中发挥作用。mcd1突变体在姐妹染色单体黏连和染色体凝聚方面存在缺陷。Mcd1p与染色体蛋白SMC家族成员之一的Smc1p之间的物理关联,进一步表明Mcd1p直接在染色体上发挥作用。这些数据表明Mcd1p是黏连和凝聚之间的一个连接点。我们提出了一个有丝分裂染色体结构模型,该模型纳入了这一先前未被怀疑的联系。