Transient cell cycle arrest of Saccharomyces cerevisiae by amino acid analog beta-2-DL-thienylalanine.

When treated with the amino acid analog beta-2-DL-thienylalanine, cells of the yeast Saccharomyces cerevisiae accumulated in the G1 portion of the cell cycle at the "start" event. This G1 arrest was accompanied by a rapid decrease in the rate of labeling of ribonucleic acid (RNA) with little effect on the rate of labeling of protein. When we examined which aspect of RNA metabolism was most affected by beta-2-DL-thienylalanine treatment, we found a dramatic decrease in the production of ribosomal precursor RNA. These results are consistent with previous findings which show a correlation between G1 arrest and reduced ribosomal precursor RNA production. The G1 arrest brought about be beta-2-DL-thienylalanine was transient; cells remain arrested in G1 only for several hours. Release from G1 arrest appeared to be accompanied either by metabolism or sequestration of the analog.