Tra1 as a screening target for transcriptional activation domain discovery.
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ABSTRACT:
SUBMITTER: Majmudar CY
PROVIDER: S-EPMC4322765 | biostudies-literature | 2009 Jul
REPOSITORIES: biostudies-literature
Publications
Tra1 as a screening target for transcriptional activation domain discovery.
Majmudar Chinmay Y CY Labut Anne E AE Mapp Anna K AK
Bioorganic & medicinal chemistry letters 20090518 14
There is tremendous interest in developing activator artificial transcription factors that functionally mimic endogenous transcriptional activators for use as mechanistic probes, as components of synthetic cell circuitry, and in transcription-targeted therapies. Here, we demonstrate that a phage display selection against the transcriptional activation domain binding motif of the coactivator Tra1(TRRAP) produces distinct sequences that function with similar binding modes and potency as natural ac ...[more]
Similar Datasets
Project description:Tra1 is an essential component of the S. cerevisiae SAGA and NuA4 complexes. Using targeted mutagenesis, we identified residues within its C-terminal phosphatidylinositol-3 kinase (PI3K) domain that are required for function. The phenotype of tra1-P3408A, S3463A and SRR3413-3415AAA included temperature sensitivity and reduced growth in media containing 6% ethanol or aminotriazole. These alleles resulted in ≥2-fold change in expression of ~7% of yeast genes in rich media and reduced activation of PHO5 and ADH2 promoters. Tra1-SRR3413 associated with components of both the NuA4 and SAGA complexes and with the Gal4 transcriptional activation domain similar to wild-type protein. Tra1-SRR3413 resulted in a decreased ratio of acetylated histone H3 and H4 to total histone H3 at the PHO5 promoter that appeared largely due to increased unacetylated histone. Slow growth of a tra1-SRR3413 strain in aminotriazole was suppressed by deletion of Vps1 and the Vps1 interacting protein, Rad16. In addition, ethanol sensitivity was suppressed by loss of Vam3, suggesting that Tra1 is involved with protein trafficking and membrane sorting. Furthermore, tra1-SRR3413 results in generation dependent telomere shortening. While the tra1 alleles have some phenotypic similarities with deletions of SAGA and/or NuA4 components, the pattern of gene expression, genetic interactions and telomere shortening suggest possible novel functions for the PI3K-domain of Tra1. Keywords: yeast, Tra1, PI3-kinase domain, gene expression, genetic modification
2007-10-10 | GSE6847 | GEO
Project description:Tra1 is a component of the Saccharomyces cerevisiae SAGA and NuA4 complexes and a member of the phosphatidylinositol 3-kinase (PI3K) related kinase family that contain a C- terminal PI3K domain followed by a ~ 35-residue FATC domain. We have characterized four alleles with single residue changes in the FATC domain. Of these tra1-L3733A had the most pronounced effects with phenotypes including temperature and cold sensitivity, and reduced growth in media containing ethanol, Calcofluor white, rapamycin, chloramphenicol and geneticin. Tra1-L3733A interacted at normal levels with components of the NuA4 and SAGA complexes, and did not significantly alter histone acetylation patterns. The tra1-L3733A allele resulted in two-fold or greater change in expression of approximately 11% of yeast genes in rich media. Of the 279 genes with increased expression, 175 were ribosomal subunits or involved in ribosomal function or biogenesis. Elevated levels of Pol I and Pol III transcripts were also observed. The phenotypes of the tra1-L3733A overlapped with but were not identical to strains containing deletions of SAGA or NuA4 components or with strains containing mutations in the PI3K domain. Our finding that the double mutant allele, tra1-SRR3413/L3733A with alterations in the PI3K and FATC domains, resulted in wild type growth, suggests a model whereby the FATC domain negatively regulates the activity of the PI3K domain. Expression of genes involved in ribosome biosynthesis, other than the ribosomal subunits themselves, returned to near normal levels in the double mutant strain. We also characterized tra1-G3745, which contains an additional glycine residue following the normal C-terminal phenylalanine. This allele did not support viability and showed severe dominant negative effects. In contrast to what was observed for tra1-L3733A, tra1-G4745 resulted in decreased expression of genes required for ribosome biogenesis and did not interact with Esa1 or Spt7.
2011-09-20 | GSE13561 | GEO
Project description:Gene expression undergoes considerable changes during the aging process. The mechanisms regulating the transcriptional response to cellular aging remain poorly understood. Here, we employ the budding yeast Saccharomyces cerevisiae to better understand how organisms adapt their transcriptome to promote longevity. Chronological lifespan assays in yeast measure the survival of nondividing cells at stationary phase over time, providing insights into the aging process of postmitotic cells. Tra1 is an essential component of both the yeast Spt-Ada-Gcn5 acetyltransferase/Spt-Ada-Gcn5 acetyltransferase-like and nucleosome acetyltransferase of H4 complexes, where it recruits these complexes to acetylate histones at targeted promoters. Importantly, Tra1 regulates the transcriptional response to multiple stresses. To evaluate the role of Tra1 in chronological aging, we took advantage of a previously characterized mutant allele that carries mutations in the TRA1 PI3K domain (tra1Q3). We found that loss of functions associated with tra1Q3 sensitizes cells to growth media acidification and shortens lifespan. Transcriptional profiling reveals that genes differentially regulated by Tra1 during the aging process are enriched for components of the response to stress. Notably, expression of catalases (CTA1, CTT1) involved in hydrogen peroxide detoxification decreases in chronologically aged tra1Q3 cells. Consequently, they display increased sensitivity to oxidative stress. tra1Q3 cells are unable to grow on glycerol indicating a defect in mitochondria function. Aged tra1Q3 cells also display reduced expression of peroxisomal genes, exhibit decreased numbers of peroxisomes, and cannot grow on media containing oleate. Thus, Tra1 emerges as an important regulator of longevity in yeast via multiple mechanisms.
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Project description:Tra1 is a component of the Saccharomyces cerevisiae SAGA and NuA4 complexes and a member of the phosphatidylinositol 3-kinase (PI3K) related kinase family that contain a C- terminal PI3K domain followed by a ~ 35-residue FATC domain. We have characterized four alleles with single residue changes in the FATC domain. Of these tra1-L3733A had the most pronounced effects with phenotypes including temperature and cold sensitivity, and reduced growth in media containing ethanol, Calcofluor white, rapamycin, chloramphenicol and geneticin. Tra1-L3733A interacted at normal levels with components of the NuA4 and SAGA complexes, and did not significantly alter histone acetylation patterns. The tra1-L3733A allele resulted in two-fold or greater change in expression of approximately 11% of yeast genes in rich media. Of the 279 genes with increased expression, 175 were ribosomal subunits or involved in ribosomal function or biogenesis. Elevated levels of Pol I and Pol III transcripts were also observed. The phenotypes of the tra1-L3733A overlapped with but were not identical to strains containing deletions of SAGA or NuA4 components or with strains containing mutations in the PI3K domain. Our finding that the double mutant allele, tra1-SRR3413/L3733A with alterations in the PI3K and FATC domains, resulted in wild type growth, suggests a model whereby the FATC domain negatively regulates the activity of the PI3K domain. Expression of genes involved in ribosome biosynthesis, other than the ribosomal subunits themselves, returned to near normal levels in the double mutant strain. We also characterized tra1-G3745, which contains an additional glycine residue following the normal C-terminal phenylalanine. This allele did not support viability and showed severe dominant negative effects. In contrast to what was observed for tra1-L3733A, tra1-G4745 resulted in decreased expression of genes required for ribosome biogenesis and did not interact with Esa1 or Spt7. Three biological replicate experiments including one dye-swap were performed for yeast strains CY3003(TRA1::Tn10LUK with IB150(myc9-tra1_L3733A-YCplac111)) and CY3015(TRA1::Tn10LUK with IB157(myc9-tra1_SRR3413_L3733A-YCplac111)) with reference to CY2706(TRA1::Tn10LUK with 1980(myc9-TRA1-YCplac111)). Similarly, three biological replicate experiments including one dye-swap were performed for yeast strain CY3019(TRA1::Tn10LUK with 1259(myc-TRA1-YCplac111) and IB162(myc9-tra1_G3745-YCplac111)) with reference to CY3020(TRA1::Tn10LUK with 1259(myc-TRA1-YCplac111) and IB160(myc9-TRA1-YCplac111)).
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Project description:Tra1 is a component of the Saccharomyces cerevisiae SAGA and NuA4 complexes and a member of the PIKK family, which contain a C-terminal phosphatidylinositol 3-kinase-like (PI3K) domain followed by a 35-residue FATC domain. Single residue changes of L3733A and F3744A, within the FATC domain, resulted in transcriptional changes and phenotypes that were similar but not identical to those caused by mutations in the PI3K domain or deletions of other SAGA or NuA4 components. The distinct nature of the FATC mutations was also apparent from the additive effect of tra1-L3733A with SAGA, NuA4, and tra1 PI3K domain mutations. Tra1-L3733A associates with SAGA and NuA4 components and with the Gal4 activation domain, to the same extent as wild-type Tra1; however, steady-state levels of Tra1-L3733A were reduced. We suggest that decreased stability of Tra1-L3733A accounts for the phenotypes since intragenic suppressors of tra1-L3733A restored Tra1 levels, and reducing wild-type Tra1 led to comparable growth defects. Also supporting a key role for the FATC domain in the structure/function of Tra1, addition of a C-terminal glycine residue resulted in decreased association with Spt7 and Esa1, and loss of cellular viability. These findings demonstrate the regulatory potential of mechanisms targeting the FATC domains of PIKK proteins.
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Project description:Tra1 is an essential component of the Saccharomyces cerevisiae SAGA and NuA4 complexes. Using targeted mutagenesis, we identified residues within its C-terminal phosphatidylinositol-3-kinase (PI3K) domain that are required for function. The phenotypes of tra1-P3408A, S3463A, and SRR3413-3415AAA included temperature sensitivity and reduced growth in media containing 6% ethanol or calcofluor white or depleted of phosphate. These alleles resulted in a twofold or greater change in expression of approximately 7% of yeast genes in rich media and reduced activation of PHO5 and ADH2 promoters. Tra1-SRR3413 associated with components of both the NuA4 and SAGA complexes and with the Gal4 transcriptional activation domain similar to wild-type protein. Tra1-SRR3413 was recruited to the PHO5 promoter in vivo but gave rise to decreased relative amounts of acetylated histone H3 and histone H4 at SAGA and NuA4 regulated promoters. Distinct from other components of these complexes, tra1-SRR3413 resulted in generation-dependent telomere shortening and synthetic slow growth in combination with deletions of a number of genes with roles in membrane-related processes. While the tra1 alleles have some phenotypic similarities with deletions of SAGA and NuA4 components, their distinct nature may arise from the simultaneous alteration of SAGA and NuA4 functions.
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