Shipman C, Smith S H, Drach J C
Proc Natl Acad Sci U S A. 1972 Jul;69(7):1753-7. doi: 10.1073/pnas.69.7.1753.
The drug, 9-beta-D-arabinofuranosyl adenine, selectively inhibits the synthesis of nuclear DNA without affecting extrachromosomal DNA synthesis in rat cells transformed by Rous sarcoma virus (B-mix K-44/6). The inhibition was linear with respect to drug concentration over the range of 37-600 muM. Mitosis and total synthesis of DNA per cell were also depressed. DNA synthesis was determined by measurement of [(3)H]thymidine incorporation into DNA. Covalently-closed circular DNA was extracted by the Hirt procedure and separated from residual chromosomal DNA by buoyant density gradient ultracentrifugation in CsCl-propidium diiodide. On the basis of buoyant density and sedimentation velocity centrifugation, the covalently-closed circular DNA formed in the presence of the drug was indistinguishable from that formed in its absence.
药物9-β-D-阿拉伯呋喃糖基腺嘌呤可选择性抑制核DNA的合成,而不影响劳斯肉瘤病毒(B-mix K-44/6)转化的大鼠细胞中的染色体外DNA合成。在37 - 600μM范围内,抑制作用与药物浓度呈线性关系。每个细胞的有丝分裂和DNA总合成也受到抑制。通过测量[³H]胸苷掺入DNA来测定DNA合成。采用Hirt方法提取共价闭合环状DNA,并通过在CsCl-碘化丙啶中进行浮力密度梯度超速离心将其与残留的染色体DNA分离。基于浮力密度和沉降速度离心,在药物存在下形成的共价闭合环状DNA与不存在药物时形成的DNA无法区分。