Mezzina M, Suarez H G, Cassingena R, Sarasin A
Nucleic Acids Res. 1982 Aug 25;10(16):5073-84. doi: 10.1093/nar/10.16.5073.
The DNA ligase activity has been studied in 5-iodo-2'-deoxyuridine (IUdR), mitomycin C (MMC) and IUdR + MMC-treated SV40-infected or mock-infected CV1C11 monkey kidney cells. The results have shown that : 1. The level of enzyme activity is about two or three times higher in IUdR or MMC-treated non-infected cells; 2. SV40 infection doubles the level of ligase activity in the untreated cells; 3. There is an additional increase of ligase activity in IUdR or MMC-treated SV40-infected cells; 4. When infected or mock-infected cells are treated with IUdR + MMC, there is no modification of the results obtained with each drug alone; 5. Two peaks of different S values are detected in a partial purification of the drug(s) or viral induced enzyme(s). The increase in the ligase activity in drug-treated cells is independent of semi-conservative DNA synthesis. The drug(s) and viral-induced enzyme(s) is the consequence of a "de novo" synthesis of proteins, as shown by cycloheximide treatment.
已对5-碘-2'-脱氧尿苷（IUdR）、丝裂霉素C（MMC）以及IUdR + MMC处理的感染SV40或模拟感染的CV1C11猴肾细胞中的DNA连接酶活性进行了研究。结果表明：1. 在IUdR或MMC处理的未感染细胞中，酶活性水平约高两到三倍；2. SV40感染使未处理细胞中的连接酶活性水平翻倍；3. 在IUdR或MMC处理的感染SV40的细胞中，连接酶活性有额外增加；4. 当感染或模拟感染的细胞用IUdR + MMC处理时，单独使用每种药物所获得的结果没有改变；5. 在对药物或病毒诱导的酶进行部分纯化时，检测到两个不同S值的峰。药物处理细胞中连接酶活性的增加与半保留DNA合成无关。如用环己酰亚胺处理所示，药物和病毒诱导的酶是蛋白质“从头”合成的结果。
