Global regulation by the yeast Spt10 protein is mediated through chromatin structure and the histone upstream activating sequence elements.
The yeast SPT10 gene encodes a putative histone acetyltransferase (HAT) implicated as a global transcription regulator acting through basal promoters. Here we address the mechanism of this global regulation. Although microarray analysis confirmed that Spt10p is a global regulator, Spt10p was not detected at any of the most strongly affected genes in vivo. In contrast, the presence of Spt10p at the core histone gene promoters in vivo was confirmed. Since Spt10p activates the core histone genes, a shortage of histones could occur in spt10Delta cells, resulting in defective chromatin structure and a consequent activation of basal promoters. Consistent with this hypothesis, the spt10Delta phenotype can be rescued by extra copies of the histone genes and chromatin is poorly assembled in spt10Delta cells, as shown by irregular nucleosome spacing and reduced negative supercoiling of the endogenous 2mum plasmid. Furthermore, Spt10p binds specifically and highly cooperatively to pairs of upstream activating sequence elements in the core histone promoters [consensus sequence, (G/A)TTCCN(6)TTCNC], consistent with a direct role in histone gene regulation. No other high-affinity sites are predicted in the yeast genome. Thus, Spt10p is a sequence-specific activator of the histone genes, possessing a DNA-binding domain fused to a likely HAT domain.
Eriksson
Peter R
PR
Laboratory of Molecular Growth Regulation, National Instistute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Mendiratta
Geetu
G
McLaughlin
Neil B
NB
Wolfsberg
Tyra G
TG
Mariño-Ramírez
Leonardo
L
Pompa
Tiffany A
TA
Jainerin
Mohendra
M
Landsman
David
D
Shen
Chang-Hui
CH
Clark
David J
DJ
D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002843:Chromatin / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D051548:Histone Acetyltransferases; D006657:Histones / Q000235:genetics; D008969:Molecular Sequence Data; D010641:Phenotype; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D002843:Chromatin; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D006657:Histones; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D051548:Histone Acetyltransferases; C086444:SPT10 protein, S cerevisiae