FIG. 6.

Snf3 inhibits Std1-mediated gene induction. (A) Invertase activity was measured in repressed cells (25) transformed with 2μm plasmids containing either no insert (v) or complete genomic copies of STD1 or SNF3 as indicated. Invertase activity from three independent transformants was measured, and the mean value is plotted; the error bars represent one standard error. The strains used were MSY401 (wild type) and MSY192 (std1 mth1). (B) Western blot analysis of Std1-3HA. Wild-type cells (MSY401) were transformed with the 2μm plasmids containing either no insert, the SNF3 gene, or an epitope-tagged STD1 gene. Protein extracts were prepared, and the level of the Std1-3HA protein (15 μg per lane) was detected with monoclonal antibody directed against the HA epitope.