Waqar M A, Evans M J, Manly K F, Hughes R G, Huberman J A
J Cell Physiol. 1984 Nov;121(2):402-8. doi: 10.1002/jcp.1041210218.
Previous studies on the biological effects of the 2',3'-dideoxynucleosides (ddNs) have shown that while ddAdo is lethal to E. coli, ddThd has minimal effects on the growth of mammalian cell lines and that it inhibits retrovirus infection of some cell lines but not others. Previous studies have also shown that the 5'-triphosphate of ddThd, ddTTP, selectively inhibits cellular DNA polymerases beta and gamma and retroviral reverse transcriptases. Cellular DNA polymerase alpha is relatively resistant to ddTTP. We have extended these findings to show that the 5'-triphosphates of the other 3 ddNs (ddATP, ddCTP, and ddGTP) affect cellular DNA polymerases alpha, beta, and gamma in the same fashion as does ddTTP. We also show that all four ddNs in concentrations up to 100 microM have negligible effects on the growth of NIH Swiss 3T3 cells. These negligible effects may be due to inefficient intracellular phosphorylation of each nucleoside to the triphosphate. We have determined that, in several different cell lines, ddThd is phosphorylated only at a very slow rate to ddTTP, and in the one cell line tested (monkey CV-1 cells), ddAdo and ddGuo are also poorly phosphorylated. Both ddAdo and ddGuo, and probably ddThd, are converted by CV-1 cells to additional unknown compounds which may have biological activity. The four ddNs display effects of different magnitudes on certain virus infections. Although 30 microM ddThd inhibits herpes simplex I infection of CV-1 cells by 50%, 30 microM ddAdo has no effect. Infection of NIH Swiss 3T3 cells by 334C murine leukemia virus is inhibited 70-80% by ddAdo, ddCyd, and ddThd at 50 microM, but inhibition by 50 microM ddGuo is 100%.
先前关于2'，3'-双脱氧核苷（ddNs）生物学效应的研究表明，虽然双脱氧腺苷（ddAdo）对大肠杆菌具有致死性，但双脱氧胸苷（ddThd）对哺乳动物细胞系的生长影响极小，并且它能抑制某些细胞系的逆转录病毒感染，但对其他细胞系则无此作用。先前的研究还表明，ddThd的5'-三磷酸酯（ddTTP）能选择性抑制细胞DNA聚合酶β和γ以及逆转录病毒逆转录酶。细胞DNA聚合酶α对ddTTP相对耐药。我们扩展了这些研究结果，发现其他3种ddN（ddATP、ddCTP和ddGTP）的5'-三磷酸酯对细胞DNA聚合酶α、β和γ的影响与ddTTP相同。我们还表明，浓度高达100微摩尔的所有4种ddN对NIH瑞士3T3细胞的生长影响可忽略不计。这些可忽略不计的影响可能是由于每种核苷向三磷酸酯的细胞内磷酸化效率低下所致。我们已经确定，在几种不同的细胞系中，ddThd仅以非常缓慢的速率磷酸化为ddTTP，并且在测试的一种细胞系（猴CV-1细胞）中，ddAdo和双脱氧鸟苷（ddGuo）的磷酸化也很差。ddAdo和ddGuo，可能还有ddThd，被CV-1细胞转化为其他可能具有生物活性的未知化合物。这四种ddN对某些病毒感染表现出不同程度的影响。虽然30微摩尔的ddThd可使CV-1细胞的单纯疱疹病毒I感染抑制50%，但30微摩尔的ddAdo则无作用。50微摩尔的ddAdo、双脱氧胞苷（ddCyd）和ddThd可使NIH瑞士3T3细胞受334C小鼠白血病病毒的感染抑制70 - 80%，但50微摩尔的ddGuo的抑制率为100%。
