Johnston L H, White J H, Johnson A L, Lucchini G, Plevani P
Nucleic Acids Res. 1987 Jul 10;15(13):5017-30. doi: 10.1093/nar/15.13.5017.
Using mitotic cultures synchronised by a feed-starve protocol or by elutriation, we have shown that the yeast DNA polymerase I gene is periodically expressed with its transcript increasing at least 100-fold in late G1 with a peak around the G1/S phase boundary. This is precisely the same interval of the cell cycle in which three other yeast DNA synthesis genes, CDC8, CDC9 and CDC21, have been found to be periodically expressed (White et al 1987. Expl. Cell. Res., in press). The polymerase I transcript is also regulated in meiosis, showing an overall fluctuation in level of some 20-fold, with a peak at about mid-S phase. In addition, following irradiation with 50J/m2 ultraviolet light, there was a 20-fold increase in the transcript, starting after 30 minutes and reaching a peak two hours later. These results indicate that DNA polymerase I is subject to a complex control and imply that it has a role in both DNA synthesis and DNA repair.
通过采用饥饿-投喂方案或淘洗法同步有丝分裂培养物，我们发现酵母DNA聚合酶I基因呈周期性表达，其转录本在G1晚期至少增加100倍，并在G1/S期边界附近达到峰值。这与细胞周期中另外三个酵母DNA合成基因CDC8、CDC9和CDC21被发现呈周期性表达的时间间隔完全相同（怀特等人，1987年。《实验细胞研究》，即将发表）。聚合酶I转录本在减数分裂中也受到调控，其水平总体波动约20倍，在S期中期左右达到峰值。此外，用50J/m2紫外线照射后，转录本增加了20倍，30分钟后开始增加，两小时后达到峰值。这些结果表明，DNA聚合酶I受到复杂的调控，意味着它在DNA合成和DNA修复中都发挥作用。
