THE INVESTIGATION OF CELL CYCLE REGULATORY GENES IN MAMMALIAN CELL

我们已经从金黄地鼠的BHK21细胞系中分离到了适合细胞生长的温度敏感型突变体。利用这些突变体作为DNA介导的基因转移的接收者，我们一直在克隆补充ts突变的人类基因。到目前为止，我们已经克隆了人类基因RCC1、CCG1、RPS4X和DAD1。在本研究项目下，我们克隆了RPS4X和DAD1基因，并对RCC1和CCG1基因产物的功能进行了鉴定。此外，我们还证明了编码泛素激活酶E1的人cDNA与BHK21细胞系的温度敏感突变体tsBN75互补，后者在限制性温度下表现为G2期阻滞。

We have isolated temperature sensitive mutants for cell growth from the BHK21 cell lines derived from golden hamsters. Using these mutants as a receipient of DNA-mediated gene transfer, we have been cloning human genes complementing ts mutation. So far, we have cloned human genes, RCC1, CCG1, RPS4X and DAD1. Under the present research project, we have cloned the RPS4X and DAD1 genes, and characterized the function of RCC1 and CCG1 gene-products. Additionaly, we have proved that the human cDNA encoding ubiquitin-activating enzyme E1 complements tsBN75, a temperature sensitive mutant of the BHK21 cell line which shows G2 block at restrictive temperature.