title: Cell cycle-fluctuations in concentration of various elements in cytoplasm and in nucleus/chromatin of Physarum polycephalum.
abstract: The concentrations of Na, Mg, P, Cl, S, K, and Ca (m mol/kg dry wt) were measured during the cell cycle of P. polycephalum using electron-probe X-ray microanalysis. Significant cell cycle-associated fluctuations in the concentrations of all of these elements occurs in both the cytoplasm and the nucleus. In most cases the levels of each element were elevated during mitosis but greatly reduced during the S phase. Phosphorus and sulphur were concentrated in the nucleus/chromatin at metaphase. Ultrastructural analysis of these cells reveals a phase dependent variation in the density of the cytoplasmic ground substance which is most pronounced at mitosis. The changes seen in the cytoplasm occur not only in conjunction with the increased concentration of elements in the nucleus but also with the cessation of protoplasmic migration.
mesh_terms: D002453:Cell Cycle; D002467:Cell Nucleus / Q000032:analysis*; D003593:Cytoplasm / Q000032:analysis* / Q000648:ultrastructure; D004577:Electron Probe Microanalysis; D004602:Elements; D007399:Interphase; D008677:Metaphase; D010758:Phosphorus / Q000032:analysis; D010804:Physarum / Q000166:cytology*; D011418:Prophase; D013455:Sulfur / Q000032:analysis
chemical_list: D004602:Elements; D010758:Phosphorus; D013455:Sulfur