Effect of 1-beta-D-arabinofuranosylcytosine triphosphate on DNA synthesis in isolated HeLa cell nuclei.
Effect of 1-beta-D-arabinofuranosylcytosine triphosphate on DNA synthesis in isolated HeLa cell nuclei.
复制标题
1-β-D-阿拉伯呋喃糖基胞嘧啶三磷酸对分离的 HeLa 细胞核 DNA 合成的影响。
DOI：
10.1021/bi00661a036
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发表时间：
1976
期刊：
影响因子：
2.9
通讯作者：
H. Prydz
中科院分区：
文献类型：
--
作者：
E. Wist;H. Krokan;H. Prydz
1-β-D-阿拉伯呋喃核苷5‘-三磷酸(Ara-CTP)是一种竞争性抑制同步化的S期HeLaS3细胞细胞核DNA合成的抑制剂。这种抑制作用可被DCTP逆转。其主要抑制作用是使Ara-CTP处理核的初级DNA片段在60-S脉冲作用下的伸长率降低，与对照核的215-220个核苷酸相比，约为115-120个核苷酸。初级DNA片段的起始频率可能也会降低。标记物质从初级片段到高分子量DNA的转移受到轻微的抑制，这可能是因为初级片段的生长速度降低导致后来达到连接的临界尺寸。同步化的HeLaS3细胞在分离细胞核前用1-β-D-阿拉伯糖胞嘧啶在S时相中处理2 h，使DNA合成抑制99%。在没有Ara-CTP的情况下，这些核与DNA的[~3H]TTP掺入的速率和程度都没有降低，但初级片段的结合率却降低了。
1-beta-D-Arabinofuranosylcytosine 5'-triphosphate (ara-CTP) was found to be a competitive inhibitor of DNA synthesis in nuclei isolated from synchronized S-phase HeLa S3 cells. The inhibition was reversed by dCTP. The main inhibitory effect was to reduce the rate of elongation of the primary DNA pieces from ara-CTP-treated nuclei after a 60-s pulse was about 115-120 nucleotides vs. 215-220 in control nuclei. A reduction in the frequency of initiation of primary DNA pieces probably also occurred. A slight inhibition of the transfer of labeled material from the primary pieces into high-molecular weight DNA was noted and probably arose from the fact that the reduced rate of growth of the primary pieces caused the critical size for ligation to be reached later. Synchronized HeLa S3 cells in suspension were treated with 1-beta-D-arabinofuranosylcytosine for 2 h in S-phase to give a 99% inhibition of DNA synthesis prior to isolation of nuclei. Neither the rate nor the extent of [3H]TTP incorporation into DNA decreased when such nuclei were incubated in the absence of ara-CTP, but the rate of ligation of primary pieces was reduced.