FIG. 1.

Comparison of β-galactosidase levels in extracts of yeast strain EGY48 transformed with different plasmids. The positive-control plasmid, pSH17-4, expresses a LexA DNA binding domain-GAL4 activation domain fusion protein. pEG202 expresses only the LexA DNA binding domain, pJG4-51 expresses only a B42 activation domain, pEE853 expresses a LexA DNA binding domain-DnaB fusion protein, pEE854 expresses a B42 activation domain-P2 B fusion protein, and pEE855 expresses a B42 activation domain–P2 B-rlb1 mutant fusion protein. The error bars indicate standard deviations.