Impairment of the DNA binding activity of the TATA-binding protein renders the transcriptional function of Rvb2p/Tih2p, the yeast RuvB-like protein, essential for cell growth.
In Saccharomyces cerevisiae, two highly conserved proteins, Rvb1p/Tih1p and Rvb2p/Tih2p, have been demonstrated to be major components of the chromatin-remodeling INO80 complex. The mammalian orthologues of these two proteins have been shown to physically associate with the TATA-binding protein (TBP) in vitro but not clearly in vivo. Here we show that yeast proteins interact with TBP under both conditions. To assess the functional importance of these interactions, we examined the effect of mutating both TIH2/RVB2 and SPT15, which encodes TBP, on yeast cell growth. Intriguingly, only those spt15 mutations that affected the ability of TBP to bind to the TATA box caused synthetic growth defects in a tih2-ts160 background. This suggests that Tih2p might be important in recruiting TBP to the promoter. A DNA microarray technique was used to identify genes differentially expressed in the tih2-ts160 strain grown at the restrictive temperature. Only 34 genes were significantly and reproducibly affected; some up-regulated and others down-regulated. We compared the transcription of several of these Tih2p target genes in both wild type and various mutant backgrounds. We found that the transcription of some genes depends on functions possessed by both Tih2p and TBP and that these functions are substantially impaired in the spt15/tih2-ts160 double mutants that confer synthetic growth defects.
Ohdate
Hidezumi
H
Research and Education Center for Genetic Information, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
Lim
Chun Ren
CR
Kokubo
Tetsuro
T
Matsubara
Kenichi
K
Kimata
Yukio
Y
Kohno
Kenji
K
D000251:Adenosine Triphosphatases / Q000502:physiology; D001426:Bacterial Proteins; D002455:Cell Division; D004265:DNA Helicases; D004268:DNA-Binding Proteins / Q000378:metabolism; D020869:Gene Expression Profiling; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D011485:Protein Binding; D020365:RNA Helicases / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology*; D035181:TATA-Box Binding Protein / Q000378:metabolism*; D014157:Transcription Factors; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C061260:RuvB protein, Bacteria; D029701:Saccharomyces cerevisiae Proteins; D035181:TATA-Box Binding Protein; D014157:Transcription Factors; D000251:Adenosine Triphosphatases; C428198:RVB1 protein, S cerevisiae; C428199:RVB2 protein, S cerevisiae; D004265:DNA Helicases; D020365:RNA Helicases