Chromatin remodeling during Saccharomyces cerevisiae ADH2 gene activation.
We have analyzed at both low and high resolution the distribution of nucleosomes over the Saccharomyces cerevisiae ADH2 promoter region in its chromosomal location, both under repressing (high-glucose) conditions and during derepression. Enzymatic treatments (micrococcal nuclease and restriction endonucleases) were used to probe the in vivo chromatin structure during ADH2 gene activation. Under glucose-repressed conditions, the ADH2 promoter was bound by a precise array of nucleosomes, the principal ones positioned at the RNA initiation sites (nucleosome +1), at the TATA box (nucleosome -1), and upstream of the ADR1-binding site (UAS1) (nucleosome -2). The UAS1 sequence and the adjacent UAS2 sequence constituted a nucleosome-free region. Nucleosomes -1 and +1 were destabilized soon after depletion of glucose and had become so before the appearance of ADH2 mRNA. When the transcription rate was high, nucleosomes -2 and +2 also underwent rearrangement. When spheroplasts were prepared from cells grown in minimal medium, detection of this chromatin remodeling required the addition of a small amount of glucose. Cells lacking the ADR1 protein did not display any of these chromatin modifications upon glucose depletion. Since the UAS1 sequence to which Adr1p binds is located immediately upstream of nucleosome -1, Adr1p is presumably required for destabilization of this nucleosome and for aiding the TATA-box accessibility to the transcription machinery.
Verdone
L
L
Fondazione Istituto Pasteur-Fondazione Cenci-Bolognetti, Universita "La Sapienza", Rome, Italy.
Camilloni
G
G
Di Mauro
E
E
Caserta
M
M
D000426:Alcohol Dehydrogenase / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D002843:Chromatin / Q000502:physiology*; D015825:Chromosomes, Fungal; D004794:Enzyme Repression; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005947:Glucose / Q000494:pharmacology; D007700:Kinetics; D008836:Micrococcal Nuclease; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000502:physiology; D015345:Oligonucleotide Probes; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D013104:Spheroplasts / Q000502:physiology; D016385:TATA Box; D015533:Transcriptional Activation
D002843:Chromatin; D009707:Nucleosomes; D015345:Oligonucleotide Probes; D000426:Alcohol Dehydrogenase; D008836:Micrococcal Nuclease; D005947:Glucose