All families / PF08409
PF08409: TMTC_DUF1736
Protein O-mannosyl-transferase TMTC, DUF1736
- Curation status
- SEEDED
- Seed status
- UNKNOWN CANDIDATE
- Characterization
- UNSCORED
Grounding
PF08409: Protein O-mannosyl-transferase TMTC, DUF1736
IPR013618: integrated entry for Protein O-mannosyl-transferase TMTC, DUF1736
Source description
This domain of unknown function is found in O-mannosyl -transferases TMTC1-4, and constitutes a loop between TM7 and TM8 located in the ER lumen that contains a small hydrophobic, but not membrane-embedded helix. This loop is critical for catalysis and binding of ligands, especially the lipid-linked sugar moiety [InterPro reference PUB00098068]. TMTCs transfers mannosyl residues to the hydroxyl group of serine or threonine residues. The 4 members of the TMTC family are O-mannosyl-transferases acting primarily on the cadherin superfamily; each member has distinct roles in decorating the cadherin domains with O-linked mannose glycans at specific regions. These proteins also act as O-mannosyl-transferase on other proteins such as PDIA3 [InterPro reference PUB00098069].
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
9 verified sequence examples. FASTA
| UniProt | Protein / organism | Sequence | Provenance |
|---|---|---|---|
| Q20144 | Protein O-mannosyl-transferase F38B6.6 Caenorhabditis elegans | 690 aa; version 2 UniProt 2026_03 | UNIPROT FETCH2 sibling references |
| Q56A06 | Protein O-mannosyl-transferase TMTC2 Mus musculus | 836 aa; version 1 UniProt 2026_03 | PTM REGISTRY MIRROR |
| Q5T4D3 | Protein O-mannosyl-transferase TMTC4 Homo sapiens | 741 aa; version 2 UniProt 2026_03 | UNIPROT FETCH |
| Q6ZXV5 | Protein O-mannosyl-transferase TMTC3 Homo sapiens | 915 aa; version 2 UniProt 2026_03 | UNIPROT FETCH |
| Q7K4B6 | Protein O-mannosyl-transferase Tmtc3 Drosophila melanogaster | 926 aa; version 1 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
| Q8BG19 | Protein O-mannosyl-transferase TMTC4 Mus musculus | 741 aa; version 1 UniProt 2026_03 | UNIPROT FETCH |
| Q8BRH0 | Protein O-mannosyl-transferase TMTC3 Mus musculus | 920 aa; version 2 UniProt 2026_03 | UNIPROT FETCH |
| Q8N394 | Protein O-mannosyl-transferase TMTC2 Homo sapiens | 836 aa; version 1 UniProt 2026_03 | UNIPROT FETCH2 sibling references |
| Q9VF81 | Protein O-mannosyl-transferase Tmtc4 Drosophila melanogaster | 705 aa; version 1 UniProt 2026_03 | UNIPROT FETCH2 sibling references |
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
- 6,936
- matches
- 6,939
- proteomes
- 1,367
- taxa
- 4,389
- structures
- 0
- alphafold models
- 6,079
- domain architectures
- 1,307
Classification basis
name matches duf; description says unknown function; domain of unknown function
No scoring reasons supplied.
Related Mech records
| Family | Mech | Record | Protein | Link basis |
|---|---|---|---|---|
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | dolichyl-phosphate-mannose-protein mannosyltransferase activity | Q8BRH0 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | bud outgrowth involved in lung branching | Q8BRH0 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | outer hair cell apoptotic process | Q8BG19 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | positive regulation of endoplasmic reticulum calcium ion concentration | Q8BG19 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | regulation of macromolecule metabolic process | Q7K4B6 Protein O-mannosyl-transferase Tmtc3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q20144 Protein O-mannosyl-transferase F38B6.6 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q56A06 Protein O-mannosyl-transferase TMTC2 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q5T4D3 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q6ZXV5 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8BG19 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8BRH0 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8N394 Protein O-mannosyl-transferase TMTC2 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q9VF81 Protein O-mannosyl-transferase Tmtc4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | trait identifier | |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q20144 Protein O-mannosyl-transferase F38B6.6 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q56A06 Protein O-mannosyl-transferase TMTC2 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q5T4D3 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q6ZXV5 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8BG19 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8BRH0 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q8N394 Protein O-mannosyl-transferase TMTC2 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | Q9VF81 Protein O-mannosyl-transferase Tmtc4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Protein O-mannosyl-transferase TMTC, DUF1736 | trait identifier | |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Tetratricopeptide repeat | Q5T4D3 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Tetratricopeptide repeat | Q6ZXV5 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Tetratricopeptide repeat | Q8BG19 Protein O-mannosyl-transferase TMTC4 | canonical example family classification |
| TMTC_DUF1736 (PF08409) | ProteinTraitsMech | Tetratricopeptide repeat | Q6ZXV5 Protein O-mannosyl-transferase TMTC3 | canonical example family classification |
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.