title: In vivo changes of nucleosome positioning in the pretranscription state.
abstract: The involvement of chromatin structure and organization in transcriptional regulatory pathways has become evident. One unsolved question concerns the molecular mechanisms of chromatin remodeling during in vivo promoter activation. By using a high resolution in vivo analysis we show that when yeast cells are exposed to a regulatory signal the positions of specific nucleosomes change. The system analyzed consists of the basic elements of the Saccharomyces cerevisiae ADH2 promoter, two nucleosomes of which are shown to change the distribution of their positions by few nucleotides in the direction of transcription when the glucose content of the medium is lowered. Such repositioning does not occur in the absence of the ADH2 transcriptional activator Adr1 or in the presence of its DNA-binding domain alone. A construct consisting of the DNA-binding domain plus a 43-amino acid peptide containing the Adr1 activation domain is sufficient to induce the same effect of the full-length protein. Nucleosome repositioning occurs even when the catalytic activity of the RNA polymerase II is impaired, suggesting that the Adr1 activation domain mediates the recruitment of some factor to correctly preset the relevant sequences for the subsequent transcription steps.
authors.affiliation: Centro di Studio per gli Acidi Nucleici, CNR, and Fondazione Istituto Pasteur-Fondazione Cenci Bolognetti, c/o Dipartimento di Genetica e Biologia Molecolare, Università La Sapienza, P. le Aldo Moro 5, Rome 00185, Italy.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Di Mauro
authors.forename: Loredana
authors.initials: L
authors.lastname: Verdone
authors.forename: Barbara
authors.initials: B
authors.lastname: Chiappini
authors.forename: Micaela
authors.initials: M
authors.lastname: Caserta
mesh_terms: D015152:Blotting, Northern; D002384:Catalysis; D002843:Chromatin / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry; D008957:Models, Genetic; D009707:Nucleosomes / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013696:Temperature; D014157:Transcription Factors / Q000737:chemistry; D014158:Transcription, Genetic
chemical_list: C074682:ADR1 protein, S cerevisiae; D002843:Chromatin; D004268:DNA-Binding Proteins; D009707:Nucleosomes; D010455:Peptides; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D012313:RNA