期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:12
页码:7049-7053
DOI:10.1073/pnas.77.12.7049
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Aphidicolin, a tetracyclic diterpenoid antibiotic, is a specific inhibitor of DNA synthesis in vivo and DNA polymerase (deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7 ) alpha of eukaryotic organisms. After ethyl methanesulfonate mutagenesis, we have recovered mutants of Drosophila melanogaster Schneider cell line no. 2 that grow at concentrations of aphidicolin that completely inhibit wild-type cells. The DNA polymerase alpha from one of these mutants, aph-10, is much more resistant to inhibition by the drug; the apparent Ki of the wild-type enzyme is 12 nM aphidicolin, whereas the apparent Ki of the aph-10 polymerase is more than 100 nM. (The apparent Km for dCTP is the same for both enzymes.) Another mutant, aph-13, overproduces DNA polymerase alpha at least 8-fold. The DNA polymerase of this mutant has the same apparent Km and Ki for dNTPs and aphidicolin as does wild-type polymerase.