Source 1review2001Journal of Biological Chemistry
Toolkit/p160 nuclear receptor coactivator family
p160 nuclear receptor coactivator family
Also known as: p/CIP/A1B1/ACTR/RAC/TRAM-1, SRC-1/NCOA1, TIF2/GRIP1
Taxonomy: Mechanism Branch / Architecture. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
Several insights into the mechanisms by which coactivator complexes are recruited to nuclear receptors in a ligand-dependent manner have been provided by the initial identification of the p160 family of nuclear receptor coactivators... members of the p160 family have been suggested to function as coactivators, at least in part, by serving as adapter molecules that recruit CBP and/or p300 complexes to promoter-bound nuclear receptors in a ligand-dependent manner.
Usefulness & Problems
Why this is useful
The p160 family is described as a set of nuclear receptor coactivators that bind liganded receptors and help recruit additional coactivator machinery. Their central receptor-interaction region and C-terminal activation domains support this adapter role.; adapter-mediated recruitment of coactivator complexes to nuclear receptors; studying ligand-dependent transcriptional activation mechanisms
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The p160 family is described as a set of nuclear receptor coactivators that bind liganded receptors and help recruit additional coactivator machinery. Their central receptor-interaction region and C-terminal activation domains support this adapter role.
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adapter-mediated recruitment of coactivator complexes to nuclear receptors
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studying ligand-dependent transcriptional activation mechanisms
Problem solved
They help bridge receptor binding to chromatin-modifying and transcription-promoting complexes. This addresses how ligand binding is converted into promoter activation.; links liganded nuclear receptors to downstream coactivator complexes such as CBP/p300
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They help bridge receptor binding to chromatin-modifying and transcription-promoting complexes. This addresses how ligand binding is converted into promoter activation.
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links liganded nuclear receptors to downstream coactivator complexes such as CBP/p300
Problem links
links liganded nuclear receptors to downstream coactivator complexes such as CBP/p300
LiteratureThey help bridge receptor binding to chromatin-modifying and transcription-promoting complexes. This addresses how ligand binding is converted into promoter activation.
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They help bridge receptor binding to chromatin-modifying and transcription-promoting complexes. This addresses how ligand binding is converted into promoter activation.
Taxonomy & Function
Primary hierarchy
Mechanism Branch
Architecture: A reusable architecture pattern for arranging parts into an engineered system.
Mechanisms
adapter-mediated recruitment of cbp/p300 complexeschromatin remodeling and histone acetylation-associated transcriptional activationligand-dependent coactivator recruitmentligand-dependent corepressor-to-coactivator exchangelxxll motif-mediated binding to nuclear receptor ligand-binding domainsTechniques
No technique tags yet.
Target processes
transcriptionInput: Chemical
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationoperating role: regulatorswitch architecture: recruitment
Use depends on liganded nuclear receptors, intact receptor-binding domains, and access to associated factors such as CBP/p300 or methyltransferase-containing complexes. The review frames them as parts of larger multiprotein assemblies rather than standalone effectors.; requires ligand-dependent receptor engagement through the ligand binding domain; depends on associated coactivator complexes for full transcriptional effects
They do not by themselves explain all receptor specificity or all activation outcomes, because multiple factors act sequentially and combinatorially. The review also notes promoter- and cell-specific usage of different coregulatory complexes.; the number of potential coregulators exceeds the capacity for direct interaction by a single receptor; specificity appears promoter- and cell-dependent
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 source2 linked approval claimsfirst-pass slug p160-nuclear-receptor-coactivator-family
Several insights into the mechanisms by which coactivator complexes are recruited to nuclear receptors in a ligand-dependent manner have been provided by the initial identification of the p160 family of nuclear receptor coactivators... members of the p160 family have been suggested to function as coactivators, at least in part, by serving 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
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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Comparisons
Source-stated alternatives
The review contrasts p160-family recruitment with other coactivator assemblies such as CBP/p300-associated factors and Mediator-like complexes, and with corepressor complexes used during repression.
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The review contrasts p160-family recruitment with other coactivator assemblies such as CBP/p300-associated factors and Mediator-like complexes, and with corepressor complexes used during repression.
Source-backed strengths
common domain structure supports receptor interaction and downstream coactivator recruitment; contains LXXLL motifs central to ligand-dependent receptor binding
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common domain structure supports receptor interaction and downstream coactivator recruitment
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contains LXXLL motifs central to ligand-dependent receptor binding
Compared with CBP/p300 coactivator complex
The review contrasts p160-family recruitment with other coactivator assemblies such as CBP/p300-associated factors and Mediator-like complexes, and with corepressor complexes used during repression.
Shared frame: source-stated alternative in extracted literature
Strengths here: common domain structure supports receptor interaction and downstream coactivator recruitment; contains LXXLL motifs central to ligand-dependent receptor binding.
Relative tradeoffs: the number of potential coregulators exceeds the capacity for direct interaction by a single receptor; specificity appears promoter- and cell-dependent.
Source:
The review contrasts p160-family recruitment with other coactivator assemblies such as CBP/p300-associated factors and Mediator-like complexes, and with corepressor complexes used during repression.
Ranked Citations
- 1.