MIG1-dependent and MIG1-independent regulation of GAL gene expression in Saccharomyces cerevisiae: role of Imp2p.
Imp2p (Yil154c) is a transcriptional activator involved in glucose derepression of the maltose, galactose and raffinose utilization pathways and in resistance to thermal, oxidative or osmotic stress. We analysed the role of Imp2 in the regulation of GAL genes. Imp2 was shown to have a positive effect on glucose derepression of Leloir pathway genes and their activator gene GAL4. The effect of Imp2 on galactose metabolism was shown to be partially dependent on Mig1p. The Mig1-independent role depends on Nrg1p. However, disruption of both MIG1 and NRG1 only partially relieves the glucose repression of GAL genes in the Deltaimp2 mutant, indicating that Imp2 must also have other function(s). Moreover, the interaction between IMP2 and GAL6/BLH1, a recently isolated gene involved in the regulation of GAL genes that shares with Imp2 the ability to protect cells from the glycopeptide bleomycin, was also analysed. The results suggest a major role of Imp2 in a GAL6-independent pathway.
Alberti
Adriana
A
Dipartimento di Genetica Antropologia Evoluzione, Università degli Studi di Parma, Parco Area delle Scienze 11A, 43100 Parma, Italy.
Lodi
Tiziana
T
Ferrero
Iliana
I
Donnini
Claudia
C
D000963:Antimetabolites / Q000494:pharmacology; D001761:Bleomycin / Q000494:pharmacology; D015152:Blotting, Northern; D003546:Cysteine Endopeptidases / Q000096:biosynthesis* / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal / Q000502:physiology*; D005947:Glucose / Q000378:metabolism; D016254:Mutagenesis, Insertional; D009687:Nuclear Proteins / Q000378:metabolism*; D012313:RNA / Q000737:chemistry / Q000235:genetics; D012097:Repressor Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic / Q000502:physiology*; D014170:Transformation, Genetic
D000963:Antimetabolites; D004268:DNA-Binding Proteins; C052130:GAL4 protein, S cerevisiae; C096739:IMP2 protein, S cerevisiae; C085976:MIG1 protein, S cerevisiae; C117881:NRG1 protein, S cerevisiae; D009687:Nuclear Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D001761:Bleomycin; D012313:RNA; D003546:Cysteine Endopeptidases; C031262:bleomycin hydrolase; D005947:Glucose