Yeast strains used in this study are the A346a background, and their genotypes are listed in Supplemental Table 1. Synthetic dropout and yeast extract/peptone/dextrose (YPD) media were prepared as previously described (Guacci et al., 1997 (link)). For experiments using the AID system, a 1 M stock of 3-indoleacetic acid (Sigma-Aldrich, St. Louis, MO) was made in dimethyl sulfoxide and added to plates or liquid cultures at a final concentration of 500 μM, with cooling agar used in plates to ∼55°C before addition of auxin to each batch.