McGrew J T, Xiao Z X, Fitzgerald-Hayes M
Department of Biochemistry, University of Massachusetts, Amherst 01003.
Yeast. 1989 Jul-Aug;5(4):271-84. doi: 10.1002/yea.320050407.
We have devised a genetic screen to identify trans-acting factors involved in chromosome transmission in yeast. This approach was designed to potentially identify a subset of genes encoding proteins that interact with centromere DNA. It has been shown that mutations in yeast centromere DNA cause aberrant chromosome segregation during mitosis and meiosis. We reasoned that the function of an altered centromere should be particularly sensitive to changes in factors with which it interacts. We constructed a disomic strain containing one copy of chromosome III with a wild-type centromere and one copy of chromosome III bearing the SUP11 gene and a mutant CEN3. This strain forms white colonies with red sectors due to nondisjunction of the chromosome bearing the mutant centromere. After mutagenesis we picked colonies that exhibited increased nondisjunction of the mutant chromosome as evidenced by increased red-white sectoring. Using this approach, we have isolated three trans-acting chromosome nondisjunction (cnd) mutants that are defective in maintaining chromosomes during mitosis in yeast.
我们设计了一种遗传筛选方法来鉴定参与酵母染色体传递的反式作用因子。该方法旨在潜在地鉴定出编码与着丝粒DNA相互作用的蛋白质的基因子集。研究表明，酵母着丝粒DNA中的突变会导致有丝分裂和减数分裂期间染色体异常分离。我们推断，改变的着丝粒的功能应该对与其相互作用的因子的变化特别敏感。我们构建了一个二体菌株，其中一条含有野生型着丝粒的III号染色体和一条携带SUP11基因及突变型CEN3的III号染色体。由于携带突变型着丝粒的染色体不分离，该菌株形成带有红色扇形区域的白色菌落。诱变后，我们挑选出那些表现出突变染色体不分离增加的菌落，这可通过红白扇形区域增加来证明。利用这种方法，我们分离出了三个反式作用的染色体不分离（cnd）突变体，它们在酵母有丝分裂期间维持染色体方面存在缺陷。
