Interaction of LexA-Reg1 with Snf1 fusion
proteins in the two-hybrid system. LexA-Reg1 and the indicated
activation domain fusion to Snf1 sequence were expressed from the
ADH1 promoter from plasmids listed in Table 1.
Transformants of CTY10–5d were grown in selective SC + 4% glucose
medium (high glucose, ░⃞). To obtain derepressed cells (low
glucose, ▪), transformants were shifted to SC + 0.05%
glucose for 3 to 4 h, except that transformants expressing
GAD-Snf1KDK84R and GAD were grown in SC + 2% raffinose/0.05%
glucose. Values are the average β-gal activity of four to six
transformants. In control experiments, values for VP16-Snf1K84R and
GAD-Snf1KDK84R in combination with LexA were <1. The increased
interaction detected in derepressed cells is not due to increased
expression of LexA-Reg1 (27) or Snf1 hybrid proteins (ref. 23 and data
not shown).