Source 1review2001Journal of Biological Chemistry
Toolkit/CBP/p300 coactivator complex
CBP/p300 coactivator complex
Also known as: CREB-binding protein, p300
Taxonomy: Mechanism Branch / Architecture. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
The mammalian Gcn5 orthologues, including p/CAF, CREB-binding protein (CBP), adenovirus E1A-binding protein p300, and TAFII250, each possess intrinsic histone acetyltransferase (HAT) activity... The acetyltransferase functions of factors such as CBP/p300 are directly required for enhanced transcription on chromatinized templates.
Usefulness & Problems
Why this is useful
CBP/p300 is presented as a coactivator with intrinsic histone acetyltransferase activity that promotes transcriptional activation on chromatin templates. It functions as part of larger coactivator assemblies.; histone acetylation-linked transcriptional activation; overcoming repressive chromatin structure at promoters
Source:
CBP/p300 is presented as a coactivator with intrinsic histone acetyltransferase activity that promotes transcriptional activation on chromatin templates. It functions as part of larger coactivator assemblies.
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histone acetylation-linked transcriptional activation
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overcoming repressive chromatin structure at promoters
Problem solved
It helps overcome chromatin-mediated repression by acetylating histones and supporting transcriptional activation. The review specifically links its acetyltransferase function to enhanced transcription on chromatinized templates.; provides histone acetyltransferase activity needed for enhanced transcription on chromatinized templates
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It helps overcome chromatin-mediated repression by acetylating histones and supporting transcriptional activation. The review specifically links its acetyltransferase function to enhanced transcription on chromatinized templates.
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provides histone acetyltransferase activity needed for enhanced transcription on chromatinized templates
Problem links
provides histone acetyltransferase activity needed for enhanced transcription on chromatinized templates
LiteratureIt helps overcome chromatin-mediated repression by acetylating histones and supporting transcriptional activation. The review specifically links its acetyltransferase function to enhanced transcription on chromatinized templates.
Source:
It helps overcome chromatin-mediated repression by acetylating histones and supporting transcriptional activation. The review specifically links its acetyltransferase function to enhanced transcription on chromatinized templates.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Architecture: A composed arrangement of multiple parts that instantiates one or more mechanisms.
Mechanisms
corepressor-to-coactivator exchangehistone acetylationligand-dependent coactivator recruitmentTechniques
No technique tags yet.
Target processes
recombinationtranscriptionInput: Chemical
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: multi component delivery burdenoperating role: regulatorswitch architecture: multi componentswitch architecture: recruitment
Its use depends on recruitment to promoter-bound receptors, often through higher-affinity coactivators such as p160-family proteins. A chromatinized transcription template is the context emphasized in the review.; requires recruitment through other coactivators such as p160-family factors in many cases; acts in chromatin context rather than as a simple receptor-binding factor
It is not usually described as the direct receptor-docking factor, so it does not by itself explain receptor selectivity. The review also does not present it as the only coactivator class needed for activation.; in most cases acetyltransferases are not directly recruited to nuclear receptors; recruitment depends on other coactivators with higher affinity for liganded receptors
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
CBP/p300 acetyltransferase activity is described as directly required for enhanced transcription on chromatinized templates.
Ligand-dependent exchange of corepressors for coactivators is presented as the basic mechanism by which nuclear receptors switch from gene repression to activation.
Nuclear receptor transcriptional activation is described as involving multiple factors acting sequentially and/or combinatorially to reorganize chromatin and recruit basal transcription machinery.
p160-family coactivators are described as adapter molecules that recruit CBP and/or p300 complexes to promoter-bound nuclear receptors in a ligand-dependent manner.
Two major coactivator function classes emphasized in the review are ATP-dependent nucleosome remodeling complexes and histone acetyltransferase-containing factors.
The LXXLL motif is described as necessary and sufficient for ligand-dependent interaction with nuclear receptor ligand binding domains, with specificity further influenced by additional residues and ligand-induced receptor conformation.
Approval Evidence
1 source4 linked approval claimsfirst-pass slug cbp-p300-coactivator-complex
The mammalian Gcn5 orthologues, including p/CAF, CREB-binding protein (CBP), adenovirus E1A-binding protein p300, and TAFII250, each possess intrinsic histone acetyltransferase (HAT) activity... The acetyltransferase functions of factors such as CBP/p300 are directly required for enhanced transcription on chromatinized templates.
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mechanistic summarysupports
CBP/p300 acetyltransferase activity is described as directly required for enhanced transcription on chromatinized templates.
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mechanistic summarysupports
Nuclear receptor transcriptional activation is described as involving multiple factors acting sequentially and/or combinatorially to reorganize chromatin and recruit basal transcription machinery.
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mechanistic summarysupports
p160-family coactivators are described as adapter molecules that recruit CBP and/or p300 complexes to promoter-bound nuclear receptors in a ligand-dependent manner.
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mechanistic summarysupports
Two major coactivator function classes emphasized in the review are ATP-dependent nucleosome remodeling complexes and histone acetyltransferase-containing factors.
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Comparisons
Source-stated alternatives
The review contrasts CBP/p300-type HAT complexes with ATP-dependent remodeling complexes such as SWI/SNF and with HDAC-containing corepressor complexes involved in repression.
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The review contrasts CBP/p300-type HAT complexes with ATP-dependent remodeling complexes such as SWI/SNF and with HDAC-containing corepressor complexes involved in repression.
Source-backed strengths
possesses intrinsic histone acetyltransferase activity; directly required for enhanced transcription on chromatinized templates
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possesses intrinsic histone acetyltransferase activity
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directly required for enhanced transcription on chromatinized templates
Compared with cdiGEBS
CBP/p300 coactivator complex and cdiGEBS address a similar problem space because they share recombination, transcription.
Shared frame: shared target processes: recombination, transcription; same primary input modality: chemical
Relative tradeoffs: looks easier to implement in practice.
Compared with CRISPR/Cas9
CBP/p300 coactivator complex and CRISPR/Cas9 address a similar problem space because they share recombination.
Shared frame: same top-level item type; shared target processes: recombination; same primary input modality: chemical
Strengths here: may avoid an exogenous cofactor requirement.
Relative tradeoffs: appears more independently replicated.
Compared with CRISPR/Cas9 system
CBP/p300 coactivator complex and CRISPR/Cas9 system address a similar problem space because they share recombination, transcription.
Shared frame: same top-level item type; shared target processes: recombination, transcription
Relative tradeoffs: appears more independently replicated; looks easier to implement in practice.
Ranked Citations
- 1.