Effect of inhibitors of RNA and protein synthesis on the course of mitosis in a synchronized culture of Chinese hamster cells

Abstract

The synthesis period of various types of RNA and proteins during the interphase related to the immediate after synchronization mitosis was investigated on teh synchronized culture of Chinese hamster cells with inhibitors. Analysis of MI and forms of mitosis pathology indicated the proteins functionally related to the cell division to be mainly synthesized during the second half of the interphase. The most important action of pyromycin during this time is the induction of C-mitosis on account of suppression of proteins synthesis responsible for the spiralization of chromosomes during the prophase. Inhibition of the r RNA transcription at any stage influence the cytotomy and reconstruction of daughter nuclei, this being accompanied by the delay of the cell exit from the mitosis. In difference from pyromycin, a high dose of AMD as an inhibitor of the whole cell RNA synthesis was most effective during the first half of the interphase. It is suggested that during this period at least three kinds of RNA are synthesized which are functionally related to the immediate mitosis in a different way: RNA for genome reduplication, RNA for the tubulin synthesis, and RNA which is the division spindle component.