Analysis of the time of utilization of proteins for the initiation and completion of division in synchronized Tetrahymena pyriformis.

We exposed division-synchronized Tetrahymena pyriformis to pulse treatments with the structural amino acid analogue p-fluorophenylalanine. We related the timing of the treatments to the delays in onset or completion of division, or both. The results enable us to distinguish between early and late phases in cell division in which the cells bring into action proteins which contribute to initiate and complete division, respectively. Normally, these events are separated by 25-30 min.