DNA DAMAGE BY ALKYLATING AGENTS AND THEIR REPAIR IN HUMAN TUMOR CELLS

已经表明，大约20%的人类肿瘤细胞系和病毒 转化系对烷基化剂过敏， 明显缺乏烷基鸟嘌呤烷基转移酶。 我们已经能够 从人肝中部分纯化酶。 这种酶可以去除 在鸟嘌呤的06位上烷基化损伤，但在其他位点上没有烷基化损伤。 DNA. 我们计划进一步表征这种酶，并将其纯化至 可以获得氨基酸序列信息的点。 在 与D.亚罗什，人类肝脏提取物被用来 分离足够量的这种蛋白质。 差异 在mer+和mer-细胞中特异性RNA的转录也 正在调查

It has been shown that approximately 20% of human tumor lines and viral transformed lines are hypersensitive to alkylating agents due to an apparent absence of Alkylguanine Alkyltransferase. We have been able to partially purify the enzyme from human liver. This enzyme removes alkylation damage at the 06 position of guanine but not at other sites in DNA. We plan to further characterize this enzyme and purify it to the point where amino acid sequence information can be obtained. In collaberation with D. Yarosh, human liver extracts are being used to isolate adequate quantities of this protein. Differences in the transcription of specific RNA's in mer plus and mer minus cells are also being investigated.