Aerts R J, Durston A J, Moolenaar W H
Cell. 1985 Dec;43(3 Pt 2):653-7. doi: 10.1016/0092-8674(85)90237-5.
Cytoplasmic pH (pHi) was monitored during the cell cycle of synchronous populations of Dictyostelium discoideum by means of a pH "null point" method. There is a cycle of pHi that closely corresponds to the DNA replication cycle, with a minimum of pH 7.20 in interphase and a peak of pH 7.45 during S phase and mitosis. When DNA replication is blocked by hydroxyurea, pHi continues to oscillate with a similar period as the uninhibited division cycle. Even when protein synthesis is inhibited by cycloheximide the periodic pHi cycles persist. Artificially raising pHi in exponentially growing cells by approximately 0.1 units causes a severalfold increase in the rates of protein and DNA synthesis. We conclude that an autonomous pHi oscillator exists in Dictyostelium cells, which operates independently of protein and DNA synthesis and which may have a major role in the timing and regulation of the cell cycle.
通过pH“零点”法监测了盘基网柄菌同步群体细胞周期中的细胞质pH（pHi）。存在一个与DNA复制周期密切对应的pHi循环，间期pH最小值为7.20，S期和有丝分裂期间pH峰值为7.45。当DNA复制被羟基脲阻断时，pHi继续以与未受抑制的分裂周期相似的周期振荡。即使蛋白质合成被环己酰亚胺抑制，周期性的pHi循环仍然存在。在指数生长的细胞中人为地将pHi提高约0.1个单位会导致蛋白质和DNA合成速率增加几倍。我们得出结论，盘基网柄菌细胞中存在一个自主的pHi振荡器，它独立于蛋白质和DNA合成运行，并且可能在细胞周期的定时和调节中起主要作用。
