Comparison of E1A CR3-Dependent Transcriptional Activation across Six Different Human Adenovirus Subgroups

ABSTRACT The largest E1A isoform of human adenovirus (Ad) includes a C-4 zinc finger domain within conserved region 3 (CR3) that is largely responsible for activating transcription of the early viral genes. CR3 interacts with multiple cellular factors, but its mechanism of action is modeled primarily on the basis of the mechanism for the prototype E1A protein of human Ad type 5. We expanded this model to include a representative member from each of the six human Ad subgroups. All CR3 domains tested were capable of transactivation. However, there were dramatic differences in their levels of transcriptional activation. Despite these functional variations, the interactions of these representative CR3s with known cellular transcriptional regulators revealed only modest differences. Four common cellular targets of all representative CR3s were identified: the proteasome component human Sug1 (hSug1)/S8, the acetyltransferases p300/CREB binding protein (CBP), the mediator component mediator complex subunit 23 (MED23) protein, and TATA binding protein (TBP). The first three factors appear to be critical for CR3 function. RNA interference against human TBP showed no significant reduction in transactivation by any CR3 tested. These results indicate that the cellular factors previously shown to be important for transactivation by Ad5 CR3 are similarly bound by the E1A proteins of other types. This was confirmed experimentally using a transcriptional squelching assay, which demonstrated that the CR3 regions of each Ad type could compete with Ad5 CR3 for limiting factors. Interestingly, a mutant of Ad5 CR3 (V147L) was capable of squelching wild-type Ad5 CR3, despite its failure to bind TBP, MED23, p300/CBP-associated factor (pCAF), or p300/CBP, suggestive of the possibility that an additional as yet unidentified cellular factor is required for transactivation by E1A CR3.

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Cubitus interruptus Requires DrosophilaCREB-Binding Protein To Activate wingless Expression in theDrosophila Embryo

Molecular and Cellular Biology ◽

10.1128/mcb.20.5.1616-1625.2000 ◽

2000 ◽

Vol 20 (5) ◽

pp. 1616-1625 ◽

Cited By ~ 21

Author(s):

Yang Chen ◽

R. H. Goodman ◽

Sarah M. Smolik

Keyword(s):

Transcriptional Activation ◽

Target Genes ◽

Binding Protein ◽

Point Mutations ◽

Creb Binding Protein ◽

Wild Type ◽

Interaction Domain ◽

Cubitus Interruptus

ABSTRACT CREB-binding protein (CBP) serves as a transcriptional coactivator in multiple signal transduction pathways. The Drosophilahomologue of CBP, dCBP, interacts with the transcription factors Cubitus interruptus (CI), MAD, and Dorsal (DL) and functions as a coactivator in several signaling pathways during Drosophiladevelopment, including the hedgehog (hh),decapentaplegic (dpp), and Tollpathways. Although dCBP is required for the expression of thehh target genes, wingless (wg) andpatched (ptc) in vivo, and potentiatesci-mediated transcriptional activation in vitro, it is not known that ci absolutely requires dCBP for its activity. We used a yeast genetic screen to identify several ci point mutations that disrupt CI-dCBP interactions. These mutant proteins are unable to transactivate a reporter gene regulated by cibinding sites and have a lower dCBP-stimulated activity than wild-type CI. When expressed exogenously in embryos, the CI point mutants cannot activate endogenous wg expression. Furthermore, a CI mutant protein that lacks the entire dCBP interaction domain functions as a negative competitor for wild-type CI activity, and the expression of dCBP antisense RNAs can suppress CI transactivation in Kc cells. Taken together, our data suggest that dCBP function is necessary forci-mediated transactivation of wg duringDrosophila embryogenesis.

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Transcriptional Regulation of the MDR1 Gene by Histone Acetyltransferase and Deacetylase Is Mediated by NF-Y

Molecular and Cellular Biology ◽

10.1128/mcb.18.7.4377 ◽

1998 ◽

Vol 18 (7) ◽

pp. 4377-4384 ◽

Cited By ~ 214

Author(s):

Shengkan Jin ◽

Kathleen W. Scotto

Keyword(s):

Transcriptional Activation ◽

Histone Acetyltransferase ◽

Binding Protein ◽

Trichostatin A ◽

Present Report ◽

Dominant Negative ◽

Creb Binding Protein ◽

Wild Type ◽

Ccaat Box

ABSTRACT Recent studies have shown that the histone-modifying enzymes histone acetyltransferase (HAT) and histone deacetylase (HDAC) are involved in transcriptional activation and repression, respectively. However, little is known about the endogenous genes that are regulated by these enzymes or how specificity is achieved. In the present report, we demonstrate that HAT and HDAC activities modulate transcription of the P-glycoprotein-encoding gene, MDR1. Incubation of human colon carcinoma SW620 cells in 100-ng/ml trichostatin A (TSA), a specific HDAC inhibitor, increased the steady-state level ofMDR1 mRNA 20-fold. Furthermore, TSA treatment of cells transfected with a wild-type MDR1 promoter/luciferase construct resulted in a 10- to 15-fold induction of promoter activity. Deletion and point mutation analysis determined that an inverted CCAAT box was essential for this activation. Consistent with this observation, overexpression of p300/CREB binding protein-associated factor (P/CAF), a transcriptional coactivator with intrinsic HAT activity, activated the wild-type MDR1 promoter but not a promoter containing a mutation in the CCAAT box; deletion of the P/CAF HAT domain abolished activation. Gel shift and supershift analyses identified NF-Y as the CCAAT-box binding protein in these cells, and cotransfection of a dominant negative NF-Y expression vector decreased the activation of the MDR1promoter by TSA. Moreover, NF-YA and P/CAF were shown to interact in vitro. This is the first report of a natural promoter that is modulated by HAT and HDAC activities in which the transcription factor mediating this regulation has been identified.

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Dissection of a carboxy-terminal region of the yeast regulatory protein RAP1 with effects on both transcriptional activation and silencing

Molecular and Cellular Biology ◽

10.1128/mcb.12.3.1209-1217.1992 ◽

1992 ◽

Vol 12 (3) ◽

pp. 1209-1217

Author(s):

C F Hardy ◽

D Balderes ◽

D Shore

Keyword(s):

Dna Binding ◽

Binding Site ◽

Transcriptional Activation ◽

Binding Sites ◽

Binding Protein ◽

Binding Domain ◽

Dominant Negative Effect ◽

Dna Binding Domain ◽

Wild Type ◽

Carboxy Terminal

RAP1 is an essential sequence-specific DNA-binding protein in Saccharomyces cerevisiae whose binding sites are found in a large number of promoters, where they function as upstream activation sites, and at the silencer elements of the HMR and HML mating-type loci, where they are important for repression. We have examined the involvement of specific regions of the RAP1 protein in both repression and activation of transcription by studying the properties of a series of hybrid proteins containing RAP1 sequences fused to the DNA-binding domain of the yeast protein GAL4 (amino acids 1 to 147). GAL4 DNA-binding domain/RAP1 hybrids containing only the carboxy-terminal third of the RAP1 protein (which lacks the RAP1 DNA-binding domain) function as transcriptional activators of a reporter gene containing upstream GAL4 binding sites. Expression of some hybrids from the strong ADH1 promoter on multicopy plasmids has a dominant negative effect on silencers, leading to either partial or complete derepression of normally silenced genes. The GAL4/RAP1 hybrids have different effects on wild-type and several mutated but functional silencers. Silencers lacking either an autonomously replicating sequence consensus element or the RAP1 binding site are strongly derepressed, whereas the wild-type silencer or a silencer containing a deletion of the binding site for another silencer-binding protein, ABF1, are only weakly affected by hybrid expression. By examining a series of GAL4 DNA-binding domain/RAP1 hybrids, we have mapped the transcriptional activation and derepression functions to specific parts of the RAP1 carboxy terminus.(ABSTRACT TRUNCATED AT 250 WORDS)

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The TATA-binding protein is not an essential target of the transcriptional activators Gal4p and Gcn4p in Saccharomyces cerevisiae

Biochemical Journal ◽

10.1042/bj20021548 ◽

2003 ◽

Vol 370 (1) ◽

pp. 141-147 ◽

Cited By ~ 5

Author(s):

Christine BONGARDS ◽

Boon Shang CHEW ◽

Norbert LEHMING

Keyword(s):

Transcriptional Activation ◽

Binding Protein ◽

Tata Binding Protein ◽

Limiting Factors ◽

Clear Correlation ◽

Limiting Factor ◽

Local Concentration ◽

Transcriptional Activators ◽

Transcription Process

According to the recruitment model, transcriptional activators work by increasing the local concentration of one or several limiting factors for the transcription process at the target promoter. The TATA-binding protein Tbp1 has been considered as a likely candidate for such a limiting factor. We have used a series of Gal4p and Tbp1 mutants to correlate the in vivo interaction between the two proteins with the strength of activation. We find a clear correlation between activation strength and in vivo interaction for the series of Gal4p mutants. Consistently, the weaker activator Gcn4p does not interact with Tbp1. However, a corresponding analysis of the series of Tbp1 mutants revealed that Tbp1 is not an essential target of the acidic activators Gal4p and Gcn4p. Furthermore, detailed analysis of a Tbp1 mutant deficient for transcriptional activation by Gal4p revealed that the mutant is defective in interactions with five other proteins involved in the process of transcription.

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The N-Terminal Domain of p73 Interacts with the CH1 Domain of p300/CREB Binding Protein and Mediates Transcriptional Activation and Apoptosis

Molecular and Cellular Biology ◽

10.1128/mcb.20.4.1299-1310.2000 ◽

2000 ◽

Vol 20 (4) ◽

pp. 1299-1310 ◽

Cited By ~ 62

Author(s):

Xiaoya Zeng ◽

Xiaorong Li ◽

Ashley Miller ◽

Zhimin Yuan ◽

Wuchao Yuan ◽

...

Keyword(s):

Transcriptional Activation ◽

Binding Protein ◽

Small Cell Lung Carcinoma ◽

Creb Binding Protein ◽

Cell Lung Carcinoma ◽

Cell Extracts ◽

N Terminus ◽

Mcf 7

ABSTRACT The newly identified p53 homolog p73 mimics the transcriptional function of p53. We have investigated the regulation of p73's transcriptional activity by p300/CREB binding protein (CBP). p73-p300 complexes were identified in HeLa cell extracts by cofractionation and coimmunoprecipitation assays. The p73-p300 interaction was confirmed in vitro by glutathione S-transferase–protein association assays and in vivo by coimmunoprecipitating the overexpressed p300 and p73 in human p53-free small-cell lung carcinoma H1299 or osteosarcoma Saos-2 cells. The N terminus but not the N-terminal truncation of p73 bound to the CH1 domain (amino acids [aa] 350 to 450) of p300/CBP. Accordingly, this p73 N-terminal deletion was unable to activate transcription or to induce apoptosis. Overexpression of either p300 or CBP stimulated transcription mediated by p73 but not its N-terminally deleted mutant in vivo. The N-terminal fragment from aa 19 to 597, but not the truncated fragment from aa 242 to 1700 of p300, reduced p73-mediated transcription markedly. p73-dependent transcription or apoptosis was partially impaired in either p300- or CBP-deficient human breast carcinoma MCF-7 or H1299 cells, suggesting that both coactivators mediate transcription by p73 in cells. These results demonstrate that the N terminus of p73 directly interacts with the N-terminal CH1 domain of p300/CBP to activate transcription.

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Dissection of a carboxy-terminal region of the yeast regulatory protein RAP1 with effects on both transcriptional activation and silencing.

Molecular and Cellular Biology ◽

10.1128/mcb.12.3.1209 ◽

1992 ◽

Vol 12 (3) ◽

pp. 1209-1217 ◽

Cited By ~ 49

Author(s):

C F Hardy ◽

D Balderes ◽

D Shore

Keyword(s):

Dna Binding ◽

Binding Site ◽

Transcriptional Activation ◽

Binding Sites ◽

Binding Protein ◽

Binding Domain ◽

Dominant Negative Effect ◽

Dna Binding Domain ◽

Wild Type ◽

Carboxy Terminal

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An Inactivating Point Mutation Demonstrates That Interaction of cAMP Response Element Binding Protein (CREB) with the CREB Binding Protein Is Not Sufficient for Transcriptional Activation

Journal of Biological Chemistry ◽

10.1074/jbc.270.13.7041 ◽

1995 ◽

Vol 270 (13) ◽

pp. 7041-7044 ◽

Cited By ~ 46

Author(s):

Peiqing Sun ◽

Richard A. Maurer

Keyword(s):

Point Mutation ◽

Transcriptional Activation ◽

Binding Protein ◽

Camp Response Element Binding ◽

Creb Binding Protein ◽

Camp Response Element ◽

Response Element ◽

Element Binding Protein

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Non-Canonical Activation of CREB Mediates Neuroprotection in a C. elegans Model of Excitotoxic Necrosis

10.1101/261420 ◽

2018 ◽

Cited By ~ 1

Author(s):

K. Genevieve Feldmann ◽

Ayesha Chowdhury ◽

Jessi Becker ◽

N’Gina McAlpin ◽

Taqwa Ahmed ◽

...

Keyword(s):

Transcription Factor ◽

Transcriptional Activation ◽

Binding Protein ◽

Neuroprotective Effect ◽

Camp Response Element Binding ◽

Creb Binding Protein ◽

Creb Phosphorylation ◽

C Elegans ◽

Creb Activation ◽

Specific Subset

AbstractExcitotoxicity, caused by exaggerated neuronal stimulation by Glutamate (Glu), is a major cause of neurodegeneration in brain ischemia. While we know that neurodegeneration is triggered by overstimulation of Glu-Receptors (GluRs), the subsequent mechanisms that lead to cellular demise remain controversial. Surprisingly, signaling downstream of GluRs can also activate neuroprotective pathways. The strongest evidence involves activation of the transcription factor cAMP Response Element Binding-protein (CREB), widely recognized for its importance in synaptic plasticity. Canonical views describe CREB as a phosphorylation-triggered transcription factor, where transcriptional activation involves CREB phosphorylation and association with CREB Binding Protein (CBP). However, given CREB’s ubiquitous cross-tissue expression, the multitude of cascades leading to CREB phosphorylation, and its ability to regulate thousands of genes, it remains unclear how CREB exerts closely-tailored, differential neuroprotective responses in excitotoxicity. A non-canonical, alternative cascade for activation of CREB-mediated transcription involves the CREB co-factor cAMP-regulated transcriptional co-activator (CRTC), and may be independent of CREB phosphorylation. To identify cascades that activate CREB in excitotoxicity we use a C. elegans model of neurodegeneration by excitotoxic necrosis. We demonstrate that CREB’s neuroprotective effect is conserved, and seems most effective in neurons with moderate Glu exposure. We find that factors mediating canonical CREB activation are not involved. Instead, phosphorylation-independent CREB activation in nematode excitotoxic necrosis hinges on CRTC. CREB-mediated transcription that depends on CRTC, but not on CREB phosphorylation, might lead to expression of a specific subset of neuroprotective genes. Elucidating conserved mechanisms of excitotoxicity-specific CREB activation can help us focus on core neuroprotective programs in excitotoxicity.

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Oct-1 Potentiates CREB-Driven Cyclin D1 Promoter Activation via a Phospho-CREB- and CREB Binding Protein-Independent Mechanism

Molecular and Cellular Biology ◽

10.1128/mcb.22.22.7769-7779.2002 ◽

2002 ◽

Vol 22 (22) ◽

pp. 7769-7779 ◽

Cited By ~ 48

Author(s):

Séverine Boulon ◽

Jean-Christophe Dantonel ◽

Virginie Binet ◽

Annick Vié ◽

Jean-Marie Blanchard ◽

...

Keyword(s):

Cyclin D1 ◽

Transcriptional Activation ◽

Binding Protein ◽

Protein A ◽

Cancer Cell Line ◽

Regulatory Subunit ◽

Alternative Mechanism ◽

Creb Binding Protein ◽

New Paradigm ◽

Pou Domain

ABSTRACT Cyclin D1, the regulatory subunit for mid-G1 cyclin-dependent kinases, controls the expression of numerous cell cycle genes. A cyclic AMP-responsive element (CRE), located upstream of the cyclin D1 mRNA start site, integrates mitogenic signals that target the CRE-binding factor CREB, which can recruit the transcriptional coactivator CREB-binding protein (CBP). We describe an alternative mechanism for CREB-driven cyclin D1 induction that involves the ubiquitous POU domain protein Oct-1. In the breast cancer cell line MCF-7, overexpression of Oct-1 or its POU domain strongly increases transcriptional activation of cyclin D1 and GAL4 reporter genes that is specifically dependent upon CREB but independent of Oct-1 DNA binding. Gel retardation and chromatin immunoprecipitation assays confirm that POU forms a complex with CREB bound to the cyclin D1 CRE. In solution, CREB interaction with POU requires the CREB Q2 domain and, notably, occurs with CREB that is not phosphorylated on Ser 133. Accordingly, Oct-1 also potently enhances transcriptional activation mediated by a Ser133Ala CREB mutant. Oct-1/CREB synergy is not diminished by the adenovirus E1A 12S protein, a repressor of CBP coactivator function. In contrast, E1A strongly represses CBP-enhanced transactivation by CREB phosphorylated on Ser 133. Our observation that Oct-1 potentiates CREB-dependent cyclin D1 transcriptional activity independently of Ser 133 phosphorylation and E1A-sensitive coactivator function offers a new paradigm for the regulation of cyclin D1 induction by proliferative signals.

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Magnitude of the CREB-Dependent Transcriptional Response Is Determined by the Strength of the Interaction between the Kinase-Inducible Domain of CREB and the KIX Domain of CREB-Binding Protein

Molecular and Cellular Biology ◽

10.1128/mcb.20.24.9409-9422.2000 ◽

2000 ◽

Vol 20 (24) ◽

pp. 9409-9422 ◽

Cited By ~ 57

Author(s):

Adam J. Shaywitz ◽

Simon L. Dove ◽

Jon M. Kornhauser ◽

Ann Hochschild ◽

Michael E. Greenberg

Keyword(s):

Amino Acid ◽

Amino Acid Substitution ◽

Protein Interactions ◽

Mammalian Cells ◽

Binding Protein ◽

Full Length ◽

Mutant Form ◽

Creb Binding Protein ◽

Wild Type ◽

Kix Domain

ABSTRACT The activity of the transcription factor CREB is regulated by extracellular stimuli that result in its phosphorylation at a critical serine residue, Ser133. Phosphorylation of Ser133 is believed to promote CREB-dependent transcription by allowing CREB to interact with the transcriptional coactivator CREB-binding protein (CBP). Previous studies have established that the domain encompassing Ser133 on CREB, known as the kinase-inducible domain (KID), interacts specifically with a short domain in CBP termed the KIX domain and that this interaction depends on the phosphorylation of Ser133. In this study, we adapted a recently described Escherichia coli-based two-hybrid system for the examination of phosphorylation-dependent protein-protein interactions, and we used this system to study the kinase-induced interaction between the KID and the KIX domain. We identified residues of the KID and the KIX domain that are critical for their interaction as well as two pairs of oppositely charged residues that apparently interact at the KID-KIX interface. We then isolated a mutant form of the KIX domain that interacts more tightly with wild-type and mutant forms of the KID than does the wild-type KIX domain. We show that in the context of full-length CBP, the corresponding amino acid substitution resulted in an enhanced ability of CBP to stimulate CREB-dependent transcription in mammalian cells. Conversely, an amino acid substitution in the KIX domain that weakens its interaction with the KID resulted in a decreased ability of full-length CBP to stimulate CREB-dependent transcription. These findings demonstrate that the magnitude of CREB-dependent transcription in mammalian cells depends on the strength of the KID-KIX interaction and suggest that the level of transcription induced by coactivator-dependent transcriptional activators can be specified by the strength of the activator-coactivator interaction.

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