In lactic, its transcription is induced by Cat8 and Adr1, which Jolkinolide-B results in high levels of Jen1 protein. In Nitroprusside disodium dihydrate formic acid, the glucose transcriptional repression is also released, but JEN1 mRNAs are rapidly degraded. This degradation requires Dhh1, Pat1 and Lsm1, which are known to collaborate in the activation of decapping and 59-39 mRNA decay, but not Ski7, which is involved in the 39-59 degradation of cytoplasmic mRNA by the exosome. Notably, the stability of the JEN1 mRNA increase in the dhh1 mutant was only two fold, when its accumulation was about 6 fold, suggesting additional levels of controls of Dhh1 on JEN1 mRNA steady-state. This accumulation of JEN1 mRNA in formic acid is also dependent on the presence of Nam7, but Nam7 does not act at the level of JEN1 mRNA stability. NAM7/UPF1 is involved in the NMD pathway which degrades aberrant mRNAs exhibiting a premature stop codon and ����normal���� mRNAs which present particular features, reviewed in. However, our results suggest that JEN1 mRNA is not a target of Nam7. One possibility is that Nam7 acts indirectly on JEN1 expression by regulating the levels of a transcriptional regulator of JEN1 in formic acid. In acetic acid, the regulation of JEN1 seems to be totally different. In the wild type, the JEN1 mRNA is highly expressed. Mutations of DHH1 or PAT1 decreased this expression level. GFP-fusion experiments showed that the JEN1 mRNAs are translated in the dhh1 mutant but that this lower level of mRNA expression resulted in a lower permease activity, as measured by lactate transport assays. These observations may explain the slow-growth phenotype of the dhh1 mutant in acetic acid. This effect on the mRNA levels of JEN1 in acetic acid was independent from Nam7. The fact that the inactivation of a degradation pathway can lead to a decrease in gene expression may seem counter intuitive. It was shown recently that the inactivation of the cytoplasmic 59-39 exonuclease Xrn1 or of the decapping enzyme Dcp2 leads to accumulation of long non coding RNAs, some of which being located in the promoter or in antisense position of coding genes.