GENETIC CONTROL OF SISTER CHROMATID EXCHANGE IN YEAST

为了解黄曲霉毒素的遗传控制和分子机制。 酿酒酵母中的姐妹染色单体交换， 43个姐妹染色单体水平升高的假定突变体 交易所已被隔离。我们从一种菌株中分离出的这些突变体 HIS3基因缺失，包含两个截短拷贝 在第四染色体着丝粒附近整合的HIS3基因；不相等的 HIS3基因同源区之间的姐妹染色单体交换可以 恢复功能基因。姐妹染色单体突变体升高 我们根据他们增强的形成HIS的能力来确定交换 原生营养体与对照未诱变克隆的比较。实验是 目前正在研究这些突变体的一般影响 重组、DNA损伤诱导事件、突变和 分子/酶缺陷。

In an attempt to understand the genetic control and moleculr mechanisms of sister chromatid exchange in the yeast Saccharomyces cerevisiae, forty-three putative mutants with elevated levels of sister chromatid exchange have been isolated. These mutants we isolated in a strain that is deleted for the resident HIS3 gene and that contains two truncated copies of the HIS3 genes integrated near the centromere of chromosome IV; unequal sister chromatid exchange between homologous regions of the HIS3 gene can restore the functional gene. Mutants elevated for sister chromatid exchange wee identified based on their increased ability to form HIS+ prototrophs compared to the control unmutagenized clones. Experiments are underway to characterize these mutants in terms of general effects on recombination, DNA damage induced events, mutagenesis and molecular/enzymological defects.