Requirements for chromatin reassembly during transcriptional downregulation of a heat shock gene in Saccharomyces cerevisiae.
Heat shock genes respond to moderate heat stress by a wave of transcription. The induction phase is accompanied by the massive eviction of histones, which later reassemble with DNA during the ensuing phase of transcription downregulation. In this article, we identify determinants of this reassembly throughout the heat shock protein 104 gene (HSP104) transcription unit. The results show that, although histone H3 lacking amino acids 4-30 of its N-terminal tail (H3Delta4-30) is normally deposited, reassembly of H3Delta4-40 is obliterated with an accompanying sustained transcription. On mutation of the histone chaperones Spt6p and Spt16p, but not Asf1p, reassociation of H3 with DNA is compromised. However, despite a lasting open chromatin structure, transcription ceases normally in the spt6 mutant. Thus, transcriptional downregulation can be uncoupled from histone redeposition and ongoing transcription is not required to prevent chromatin reassembly.
Jensen
Mette M
MM
Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology, University of Aarhus, Denmark.
Christensen
Marianne S
MS
Bonven
Bjarne
B
Jensen
Torben H
TH
D002843:Chromatin / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D017353:Gene Deletion; D005786:Gene Expression Regulation; D015966:Gene Expression Regulation, Fungal; D005838:Genotype; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics*; D006657:Histones / Q000737:chemistry*; D017404:In Situ Hybridization, Fluorescence; D009154:Mutation; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics*; D013997:Time Factors; D014158:Transcription, Genetic
D002843:Chromatin; D006360:Heat-Shock Proteins; D006657:Histones; D029701:Saccharomyces cerevisiae Proteins; C070972:HsP104 protein, S cerevisiae; D004247:DNA