TABLE 2.

Effects of glucose and snf1 on repression by LexA fusion proteins

Reportera	Relevant genotypeb	Expressed protein	Growth conditionc	β-Galactosidase activity (Miller units)d		Fold repression
				Without lexA operators	With lexA operators
CYC1-lacZ	WT	LexA-Mig1	High Glu	170	6.8	25
			Raf	1,090	630	1.7
		LexA-Ssn6	High Glu	230	7.6	30
			Raf	620	23	27
		LexA-Mig1ΔZ	High Glu	130	8.1	16
			Low Glu	370	140	2.6
		LexA87	High Glu	180	91	1.9
			Low Glu	1,120	390	2.9
			Raf	710	430	1.7
	snf1	LexA-Mig1ΔZ	High Glu	5.1	0.4	13
			Low Glu	4.7	0.3	16
		LexA87	High Glu	3.7	1.6	2.3
			Low Glu	2.0	2.0	1.0
LEU2-HIS3-lacZ	WT	LexA-Mig1	High Glu	95	8.3	11
			Raf	72	22	3.3
		LexA87	High Glu	94	85	1.2
			Raf	67	21	3.2

^aThe CYC1-lacZ reporter contains either no lexA operators (pLGΔ312S [18]) or four lexA operators (JK1621 [27]) 5′ to the UAS. LEU2-HIS3-lacZ contains the lacZ gene under the control of the LEU2 UAS and the HIS3 promoter with either no lexA operators (pBM2762 [40]) or one lexA operator (pMT27) 5′ to the UAS. 

^bWT, wild type. Strains were MCY829, MCY3912, and MCY2692. 

^cStrains were grown selectively in 5% glucose (high Glu) or 2% raffinose plus 0.05% glucose (Raf). Cells were also shifted from 5 to 0.05% glucose for 3 h (low Glu). 

^dβ-Galactosidase activity was assayed in permeabilized cells. Values represent the averages of results for 3 to 24 transformants. Standard errors were <20%.