Nakai G S
Cell Tissue Kinet. 1976 Nov;9(6):553-63. doi: 10.1111/j.1365-2184.1976.tb01305.x.
EAT chalone effects on nascent DNA synthesis and DNA polymerase were examined. Concentration related inhibition of 3H-thymidine (3H-TdR) incorporation into EAT cell DNA was noted over a chalone range of 50-200 mug/ml. RNA synthesis was not affected, but protein synthesis decreased an average of 82% during 3 hr. Nascent DNA pulse-labeled for 2 min was normally incorporated into bulk DNA in the presence of chalone, but crude alpha- and beta-polymerase activities were inhibited. Crude DNA polymerase for C3H mouse kidney and spleen was also partially inhibited by EAT chalone, suggesting non-specific inhibition of DNA polymerase. Preincubation studies of chalone with crude EAT DNA polymerase or 'gapped' DNA primer had no effect on chalone activity. Chalone may control mitotic activity by inhibiting alpha- and beta-polymerase activity, thereby decreasing nascent DNA synthesis. Nascent DNA is incorporated normally into bulk DNA in the presence of chalone, indicating the DNA ligase is not inhibited.
研究了EAT抑素对新生DNA合成及DNA聚合酶的影响。在50 - 200微克/毫升的抑素浓度范围内，观察到3H - 胸腺嘧啶核苷（3H - TdR）掺入EAT细胞DNA受到浓度相关的抑制。RNA合成未受影响，但在3小时内蛋白质合成平均下降了82%。在存在抑素的情况下，脉冲标记2分钟的新生DNA正常掺入总体DNA中，但粗制的α和β聚合酶活性受到抑制。EAT抑素也部分抑制了C3H小鼠肾脏和脾脏的粗制DNA聚合酶，提示对DNA聚合酶的非特异性抑制。抑素与粗制EAT DNA聚合酶或“缺口”DNA引物的预孵育研究对抑素活性没有影响。抑素可能通过抑制α和β聚合酶活性来控制有丝分裂活性，从而减少新生DNA合成。在存在抑素的情况下，新生DNA正常掺入总体DNA中，表明DNA连接酶未受抑制。
