Consequences of the lack of PKA in the repression by glucose of some representative genes. Yeast strains TPK1 TPK2 TPK3, tpk1 tpk2 tpk3 msn2 msn4, and tpk1 tpk2 tpk3 yak1 were grown on ethanol and samples were taken before the addition of glucose to the medium and 30 min after, as described in Methods. mRNA levels were measured using Affymetrix microarrays. Biological duplicates were performed. Expression data from biological replicates generally differed from the average by less than 25%. The repression factor is the quotient of the values measured in samples grown in the absence of glucose and in those incubated in the presence of glucose. Repression is considered "total" when the repression factor is no less than 70% of that measured in the reference strain in at least one of the strains lacking PKA.