Nalidixic acid causes a transient G1 arrest in the yeast Saccharomyces cerevisiae

The addition of nalidixic acid to growing cells of the yeast Saccharomyces cerevisiae resulted in a transient depression in the rate of ribosomal precursor RNA production and a transient arrest of cells in G1. Protein synthesis rates were less affected. Lower concentrations of nalidixic acid also affected RNA synthesis and progression through G1 but had no effect on protein synthesis rates. We suggest that nalidixic acid has a primary effect on RNA synthesis leading to a G1 arrest.