Fluctuations in deoxyribo- and ribonucleoside triphosphate pools during the mitotic cycle of Physarum polycephalum.

Fluctuations in the pools of deoxyribo- and ribonucleoside triphosphates have been measured during the synchronous mitotic cycle of the slime mould Physarum polycephalum. The most pronounced fluctuation of the deoxyribonucleoside triphosphates was seen shortly before and after initiation of DNA synthesis. The pools of dTTP, dATP, dCTP and dGTP expanded before initiation of DNA synthesis and decreased again in early S phase. The pools of ribonucleoside triphosphates increased during mitosis and again 1 h after mitosis and 5 h after mitosis.