Studies of Schizosaccharomyces pombe DNA polymerase alpha at different stages of the cell cycle.
Studies of Schizosaccharomyces pombe DNA polymerase alpha at different stages of the cell cycle.
复制标题
裂殖酵母 DNA 聚合酶 α 在细胞周期不同阶段的研究。
DOI：
10.1093/nar/23.21.4337
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发表时间：
1995
影响因子：
14.9
通讯作者：
Wang,TS
中科院分区：
文献类型：
--
作者：
Park,H;Davis,R;Wang,TS
The status ofSchizosaccharomyces pombe(fission yeast) DNA polymerase α was investigated at different stages of the cell cycle.S.pombeDNA polymerase a is a phosphoprotein, with serine being the exclusive phosphoamlno acid. ByIn vivopulse labeling experiments DNA polymerase a was found to be phosphorylated to a 3-fold higher level In late S phase cells compared with cells in the G2and M phases, but the steady-state level of phosphorylatlon did not vary significantly during the cell cycle. Tryptlc phosphopeptide mapping demonstrated that the phosphorylation sites of DNA polymerase a from late S phase cells were not the same as that from G2/M phase cells. DNA polymerase a partially purified from G1/S cells had a different mobility in native gels from that from G2/M phase cells. The partially purified polymerase a from G2phase cells had a higher affinity for singlestranded DNA than that from G2/M phase cells. Despite the apparent differences in cell cycle-dependent phosphorylation, mobility in native gels and affinity for DNA, the in vitro enzymatic activity of the partially purified DNA polymerase a did not appear to vary during the cell cycle. The possible biological significance of these cell cycle-dependent characteristics of DNA polymerase a is discussed.
