MECHANISM OF DNA RECOMBINATION AND REPAIR IN YEAST SACCHAROMYCES CEREVISIAE

已经鉴定了一种ATP非依赖性DNA链转移蛋白， 从有丝分裂和减数分裂的酵母中纯化和表征 酿酒酵母细胞我们分别将它们命名为STPalpha和beta。使用 抗血清和部分氨基酸序列信息 蛋白质，各自的基因已被克隆和测序。虽然 STPalpha基因（DST1）不是有丝分裂生长所必需的，而是有丝分裂生长所必需的。 减数分裂特异性同源重组的正常水平。另 另一方面，STPbeta基因（DST2）是减数分裂所必需的， 该基因的破坏突变表现出减数分裂水平降低， 同源重组以及较低水平有丝分裂同源 重组这些数据证明了STP是同源的 酵母中的重组组分和ATP非依赖性DNA链 由STP催化的转移反应在生物学上是重要的。 此外，我们已经表明，RAD3蛋白，至少在体外， 与STP蛋白质，并刺激DNA链转移反应， ATP独立的方式。 此外，还制备了抗酵母RAD 6、RAD 18和REV 3基因产物的抗血清， 已提出建立一个协议，为他们的蛋白质纯化。

An ATP-independent DNA strand-transfer protein has been identified, purified and characterized from both mitotic and meiotic Saccharomyces cerevisiae cells. We have named them STPalpha and beta, respectively. Using antiserum and the partial amino acid sequence information from the purified proteins, the respective genes have been cloned and sequenced. Although the STPalpha gene (DST1) is not required for mitotic growth, it is required for normal level of meiosis-specific homologous recombination. On the other hand, the STPbeta gene (DST2) is required for meiosis and the gene disruption mutation of the gene exhibited reduced level of meiotic homologous recombination as well as lower level of mitotic homologous recombination. These data have proven that STP is one of homologous recombination components in yeast and an ATP-independent DNA strand transfer reactions catalyzed by STP are biologically important. Furthermore, we have shown that RAD3 protein, at least in vitro, interacts with STP proteins and stimulates DNA strand-transfer reactions by an ATP-independent manner. In addition, antiserum against yeast RAD6, RAD18, and REV3 gene products have been raised to establish a protocol for their protein purification.