All families / PF01207
PF01207: Dus
Dihydrouridine synthase (Dus)
- Curation status
- SEEDED
- Seed status
- EX DUF
- Characterization
- UNSCORED
Grounding
PF01207: Dihydrouridine synthase (Dus)
IPR035587: integrated entry for Dihydrouridine synthase (Dus)
Source description
Members of this family catalyse the reduction of the 5,6-double bond of a uridine residue on tRNA. Dihydrouridine modification of tRNA is widely observed in prokaryotes and eukaryotes, and also in some archae. Most dihydrouridines are found in the D loop of t-RNAs. The role of dihydrouridine in tRNA is currently unknown, but may increase conformational flexibility of the tRNA. It is likely that different family members have different substrate specificities, which may overlap. Dus 1 (Q9HGN6 (UniProtKB protein)) from Saccharomyces cerevisiae acts on pre-tRNA-Phe, while Dus 2 (P53720 (UniProtKB protein)) acts on pre-tRNA-Tyr and pre-tRNA-Leu. Dus 1 is active as a single subunit, requiring NADPH or NADH, and is stimulated by the presence of FAD [InterPro reference PUB00014304]. Some family members may be targeted to the mitochondria and even have a role in mitochondria [InterPro reference PUB00014304].
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
19 verified sequence examples. FASTA
| UniProt | Protein / organism | Sequence | Provenance |
|---|---|---|---|
| O31546 | Probable tRNA-dihydrouridine synthase 2 Bacillus subtilis (strain 168) | 325 aa; version 1 UniProt 2026_03 | UNIPROT FETCH2 sibling references |
| O95620 | tRNA-dihydrouridine(20a/20b) synthase [NAD(P)+]-like Homo sapiens | 317 aa; version 2 UniProt 2026_03 | UNIPROT FETCH2 sibling references |
| P0ABT5 | tRNA-dihydrouridine synthase B Escherichia coli (strain K12) | 321 aa; version 1 UniProt 2026_03 | PTM REGISTRY MIRROR11 sibling references
|
| P32695 | tRNA-dihydrouridine(20/20a) synthase Escherichia coli (strain K12) | 345 aa; version 4 UniProt 2026_03 | PTM REGISTRY MIRROR13 sibling references
|
| P33371 | tRNA-dihydrouridine(16) synthase Escherichia coli (strain K12) | 315 aa; version 1 UniProt 2026_03 | PTM REGISTRY MIRROR12 sibling references
|
| P37567 | Probable tRNA-dihydrouridine synthase 1 Bacillus subtilis (strain 168) | 333 aa; version 1 UniProt 2026_03 | UNIPROT FETCH |
| P53720 | tRNA-dihydrouridine(20) synthase [NAD(P)+] Saccharomyces cerevisiae (strain ATCC 204508 / S288c) | 384 aa; version 1 UniProt 2026_03 | PTM REGISTRY MIRROR |
| P53759 | tRNA-dihydrouridine(16/17) synthase [NAD(P)(+)] Saccharomyces cerevisiae (strain ATCC 204508 / S288c) | 423 aa; version 1 UniProt 2026_03 | UNIPROT FETCH |
| Q06053 | tRNA-dihydrouridine(47) synthase [NAD(P)(+)] Saccharomyces cerevisiae (strain ATCC 204508 / S288c) | 668 aa; version 2 UniProt 2026_03 | UNIPROT FETCH |
| Q06063 | tRNA-dihydrouridine(20a/20b) synthase [NAD(P)+] Saccharomyces cerevisiae (strain ATCC 204508 / S288c) | 367 aa; version 1 UniProt 2026_03 | UNIPROT FETCH |
First 10 shown; the FASTA and family JSON contain all examples.
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
- 46,157
- matches
- 47,750
- proteomes
- 21,293
- taxa
- 34,157
- structures
- 15
- alphafold models
- 33,123
- domain architectures
- 370
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.