All families / PF06001
PF06001: RING_CBP-p300
CREB-binding protein/p300, atypical RING domain
- Curation status
- SEEDED
- Seed status
- EX DUF
- Characterization
- UNSCORED
Grounding
PF06001: CREB-binding protein/p300, atypical RING domain
IPR010303: integrated entry for CREB-binding protein/p300, atypical RING domain
Source description
CBP (CREB-binding protein) and p300 (also known as CREBBP or KAT3A and EP300 or KAT3B, respectively) are two histone acetyltransferases (HATs) that associate with and acetylate transcriptional regulators and chromatin. The catalytic core of animal CBP-p300 contains a bromodomain, a CH2 region containing a discontinuous PHD domain interrupted by this RING domain, and a HAT domain. Bromodomain-RING-PHD forms a compact module in which the RING domain is juxtaposed with the HAT substrate-binding site. This RING domain contains only a single zinc ion-binding cluster instead of two; instead of a second zinc atom, a network of hydrophobic interactions stabilizes the domain. The RING domain has an inhibitory role. Disease mutations that disrupt RING attachment lead to upregulation of HAT activity. HAT regulation may require repositioning of the RING domain to facilitate access to an otherwise partially occluded HAT active site. Plant CBP-p300 type HATs lack a bromodomain whose role in the animal animal CBP-p300's is to bind acetylated histones; it has been suggested that these plant proteins may utilise a different domain or another bromodomain protein to perform this function [InterPro reference PUB00074827]. This RING domain has also been referred to as DUF902.
Evidence and references
- InterPro entry and its literature references. PUB identifiers are internal InterPro references, not PubMed identifiers. Unresolved citations link to the originating entry.
- Frozen description source: InterPro/Pfam API
Source descriptions and links are provenance, not independent functional validation.
Evidence counts: not scored.
Curated functional assertions
No curated functional assertions supplied.
Protein sequence examples
5 verified sequence examples. FASTA
| UniProt | Protein / organism | Sequence | Provenance |
|---|---|---|---|
| B2RWS6 | Histone acetyltransferase p300 Mus musculus | 2412 aa; version 2 UniProt 2026_03 | PTM REGISTRY MIRROR |
| P34545 | Protein cbp-1 Caenorhabditis elegans | 2017 aa; version 6 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
| P45481 | Histone lysine acetyltransferase CREBBP Mus musculus | 2441 aa; version 3 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
| Q09472 | Histone acetyltransferase p300 Homo sapiens | 2414 aa; version 2 UniProt 2026_03 | PTM REGISTRY MIRROR |
| Q92793 | CREB-binding protein Homo sapiens | 2442 aa; version 3 UniProt 2026_03 | PTM REGISTRY MIRROR |
Pfam membership is not functional evidence. Whole-protein sequences do not establish domain boundaries. A coverage gap here is not absence from UniProt.
Sequences and metadata: UniProt Consortium, CC BY 4.0.
Domain matches
No residue-level domain match evidence is available in this build. Structure and AlphaFold counters do not supply coordinates or establish function.
Snapshot counters
- proteins
- 4,477
- matches
- 4,480
- proteomes
- 1,232
- taxa
- 4,016
- structures
- 36
- alphafold models
- 170
- domain architectures
- 120
Classification basis
pfam previous unknown name
No scoring reasons supplied.
Related Mech records
This family joined the worklist after the frozen cross-Mech scan, so other Mechs were not searched for it. Missing links here are not evidence that other Mechs lack it; rows shown come from mentions of a former DUF/UPF name.
No cross-Mech examples are present in the supplied snapshot.
Curation history and reviews
No retained curation events supplied.
No retained review supplied.
Record source
Status and evidence
- Seed status
- A name-based classification of frozen InterPro/Pfam metadata. UNKNOWN CANDIDATE means the metadata explicitly says the function is unknown. KNOWN HISTORICAL DUF means a DUF name matched without that wording; this heuristic is not proof of a known function and does not establish experimental characterization. EX DUF means Pfam renamed the family away from a DUF/UPF name, as recorded in Pfam's previous identifiers; a rename usually follows published work on some members but is naming history, not proof of function for every member. Some EX DUF families' current names or descriptions still say the function is unknown; their classification basis lists this, and scoring does not treat them as characterized. FALSE POSITIVE TEXT HIT means the naming rules did not match.
- Characterization
- A separate evidence-scoring result. UNSCORED means no score has been calculated; it is not evidence that the family lacks a known function. Missing scores are not negative evidence. PARTIALLY CHARACTERIZED has partial support; KNOWN HISTORICAL DUF can inherit the seed label or reflect a known-function signal. Neither label implies experimental validation.
- Evidence counts
- Source-specific signals, not unique proteins, publications, or confidence scores. Known counts Rhea reactions and experimentally supported GO molecular-function annotations. Partial counts functional/domain assignments. Context counts structural, environmental, orthology, interaction and neighborhood signals; context alone does not assign function. Repeated annotations may not be independent.
- Curation status
- Reported separately from seed classification and characterization. SNAPSHOT ONLY means no curated metadata was supplied for this build. SEEDED denotes a source-derived record, not an expert-reviewed functional claim.
- Missing counts
- Not available means the source did not supply that counter. A zero is a reported count. Not scored means evidence counts are unavailable.