Abstract: | Feulgen cytophotometry and autoradiography were used to study DNA content and DNA synthesis in starved and starved-refed Tetrahymena pyriformis GL-C. It was found that (1) the cell population shows a limited increase in cell number during starvation and this increase is restricted to the first 7 h of starvation; (2) at the end of starvation, there is a portion of the cell population whose DNA content is similar to that for standard G2 cells; (3) a significant portion of the dividing cells at the first division following refeeding in the presence of [3H]TdR are unlabeled; (4) these unlabeled cells are among the first to divide and, upon division, generally enter into a cell cycle either lacking a G1 phase or with a shortened G1 phase. |