FIG. 5.

Sir3N derepresses rDNA silencing. Strain JS231 carrying the URA3 gene inserted at the rDNA was transformed with plasmids pADH (pAAH5), pADH-SIR3N, pADH-SIR3C, and pADH-SIR3 (p2μ-ASIR3). Colonies were grown for 3 to 5 days at 30°C on medium lacking leucine, to ensure maintenance of the plasmids, and resuspended in H₂O, and 10-fold serial dilutions were plated onto medium lacking leucine (−leu) and medium lacking leucine and uracil (−leu −ura), as described in Materials and Methods. Eight independent transformants for each plasmid were tested, of which two are shown.