Redundancy of chromatin remodeling pathways for the induction of the yeast PHO5 promoter in vivo.
Induction of the yeast PHO5 and PHO8 genes leads to a prominent chromatin transition at their promoter regions as a prerequisite for transcription activation. Although induction of PHO8 is strictly dependent on Snf2 and Gcn5, there is no chromatin remodeler identified so far that would be essential for the opening of PHO5 promoter chromatin. Nonetheless, the nonessential but significant involvement of cofactors can be identified if the chromatin opening kinetics are delayed in the respective mutants. Using this approach, we have tested individually all 15 viable Snf2 type ATPase deletion mutants for their effect on PHO5 promoter induction and opening. Only the absence of Snf2 and Ino80 showed a strong delay in chromatin remodeling kinetics. The snf2 ino80 double mutation had a synthetic kinetic effect but eventually still allowed strong PHO5 induction. The same was true for the snf2 gcn5 and ino80 gcn5 double mutants. This strongly suggests a complex network of redundant and mutually independent parallel pathways that lead to the remodeling of the PHO5 promoter. Further, chromatin remodeling kinetics at a transcriptionally inactive TATA box-mutated PHO5 promoter were affected neither under wild type conditions nor in the absence of Snf2 or Gcn5. This demonstrates the complete independence of promoter chromatin opening from downstream PHO5 transcription processes. Finally, the histone variant Htz1 has no prominent role for the kinetics of PHO5 promoter chromatin remodeling.
Barbaric
Slobodan
S
Laboratory of Biochemistry, University of Zagreb, Croatia.
Luckenbach
Tim
T
Schmid
Andrea
A
Blaschke
Dorothea
D
Hörz
Wolfram
W
Korber
Philipp
P
D000135:Acid Phosphatase; D000251:Adenosine Triphosphatases; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D051548:Histone Acetyltransferases / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D007700:Kinetics; D008954:Models, Biological; D008957:Models, Genetic; D009154:Mutation; D011401:Promoter Regions, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D000099224:p300-CBP-Associated Factor
D000135:Acid Phosphatase; D000251:Adenosine Triphosphatases; D002843:Chromatin; D004268:DNA-Binding Proteins; D051548:Histone Acetyltransferases; D006657:Histones; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C493530:Htz1 protein, S cerevisiae; C501392:GCN5 protein, S cerevisiae; D000099224:p300-CBP-Associated Factor; C488916:PHO5 protein, S cerevisiae; C499333:SNF2 protein, S cerevisiae