FIGURE 3.

Elevated Ybp1 levels exhibit differential effects on inducible gene expression. A, wild-type cells were transformed with a low-copy number plasmid carrying a TRX2-lacZ reporter gene along with a vector plasmid (pRS315) or the same vector containing a fusion gene overproducing Ybp1 (PGK1-YBP1). Transformants were grown to early log phase and challenged with H₂O₂ or left untreated. At the indicated time points, samples were withdrawn and TRX2-dependent β-galactosidase activity was measured. B, the same protocol as in A was followed except oxidative stress was imposed with the addition of diamide.