FIG 8.

KOS3 expression was autoregulated by the expression state of the Chr V HMR. (A) The KOS3 gene is located ∼1 kb away from the HMRa2 gene of the Chr V HMR. (B) Derepression at the Chr V HMRa1 gene in sir2Δ and sir4Δ mutants led to a doubling of KOS3 expression. (C) KOS3 expression did not increase in the sir2Δ mutant when the gene was placed on a plasmid. The expression levels shown are relative to a wild-type strain with KOS3 at its native location. The error bars indicate standard deviations.