Fig. 1.

Suppression of the growth defect of a gcn4-103 mutation of S. cerevisiae on Phe- and Tyr-supplemented medium. Strain RH1408 (gcn4-103) was transformed with the low-copy GCN4-carrying vector (pME1083), with the low-copy URA3-carrying control vector (pRS416), with high-copy (hc) and low-copy (lc) number vectors carrying E. coli aroH fused to the ARO3 promoter [pARO3-aroH (pME1874; pME1873)], by vectors carrying E. coli aroH fused to the ARO4 promoter [pARO4-aroH (pME2391; pME2390)], and streaked out on MV medium. RH1408 was also transformed with aroH regulated by the MET25 promoter (pME1877). The WT strain RH730 was used as positive control.