PF06292: MUN

MUN domain

Curation status: SEEDED
Seed status: EX DUF
Characterization: UNSCORED

Grounding

PF06292: MUN domain
IPR010439: integrated entry for MUN domain

Source description

This entry corresponds to the MUN domain [InterPro reference PUB00097712] found in Munc13 proteins. These constitute a family of three highly homologous molecules (Munc13-1, Munc13-2 and Munc13-3) with homology to Caenorhabditis elegans unc-13p. Munc13 proteins contain a phorbol ester-binding C1 domain and two C2 domains, which are Ca2+/phospholipid binding domains. Sequence analyses have uncovered two regions called Munc13 homology domains 1 (MHD1) and 2 (MHD2) that are arranged between two flanking C2 domains. MHD1 and MHD2 domains are present in a wide variety of proteins from Arabidopsis thaliana, C. elegans, Drosophila melanogaster, mouse, rat and human, some of which may function in a Munc13-like manner to regulate membrane trafficking. Structural studies have defined MHD1 and MHD2 to be part of the larger MUN domain which forms an elongated structure composed of any pairs of alpha helices.

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

8 verified sequence examples. FASTA

UniProt	Protein / organism	Sequence	Provenance
B2RUP2	Protein unc-13 homolog D Mus musculus	1085 aa; version 2 UniProt 2026_03	PTM REGISTRY MIRROR 1 sibling references ProteinTraitsMech: UniProtKB:B2RUP2
O13683	Exocytic regulator ync13 Schizosaccharomyces pombe (strain 972 / ATCC 24843)	1237 aa; version 1 UniProt 2026_03	UNIPROT FETCH 1 sibling references ProteinTraitsMech: Pfam:PF27826
O14795	Protein unc-13 homolog B Homo sapiens	1591 aa; version 2 UniProt 2026_03	PTM REGISTRY MIRROR 2 sibling references ProteinTraitsMech: Pfam:PF06292 ProteinTraitsMech: UniProtKB:O14795
O94812	BAI1-associated protein 3 Homo sapiens	1187 aa; version 2 UniProt 2026_03	PTM REGISTRY MIRROR 2 sibling references ProteinTraitsMech: Pfam:PF06292 ProteinTraitsMech: UniProtKB:O94812
Q80TJ1	Calcium-dependent secretion activator 1 Mus musculus	1355 aa; version 3 UniProt 2026_03	UNIPROT FETCH 1 sibling references ProteinTraitsMech: Pfam:PF25341
Q86UW7	Calcium-dependent secretion activator 2 Homo sapiens	1296 aa; version 2 UniProt 2026_03	PTM REGISTRY MIRROR 2 sibling references ProteinTraitsMech: Pfam:PF25341 ProteinTraitsMech: UniProtKB:Q86UW7
Q9ULU8	Calcium-dependent secretion activator 1 Homo sapiens	1353 aa; version 3 UniProt 2026_03	UNIPROT FETCH 1 sibling references ProteinTraitsMech: Pfam:PF25341
Q9UPW8	Protein unc-13 homolog A Homo sapiens	1703 aa; version 4 UniProt 2026_03	UNIPROT FETCH 1 sibling references ProteinTraitsMech: Pfam:PF06292

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: 17,631
matches: 22,932
proteomes: 2,603
taxa: 7,010
structures: 12
alphafold models: 6,555
domain architectures: 159

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

data/families/PF06292.yaml
Family YAML in this build

Download this family (JSON)

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.