Q013G9 · FEN1_OSTTA
- ProteinFlap endonuclease 1
- GeneFEN1
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids389 (go to sequence)
- Protein existenceInferred from homology
- Annotation score3/5
Function
function
Structure-specific nuclease with 5'-flap endonuclease and 5'-3' exonuclease activities involved in DNA replication and repair. During DNA replication, cleaves the 5'-overhanging flap structure that is generated by displacement synthesis when DNA polymerase encounters the 5'-end of a downstream Okazaki fragment. It enters the flap from the 5'-end and then tracks to cleave the flap base, leaving a nick for ligation. Also involved in the long patch base excision repair (LP-BER) pathway, by cleaving within the apurinic/apyrimidinic (AP) site-terminated flap. Acts as a genome stabilization factor that prevents flaps from equilibrating into structures that lead to duplications and deletions. Also possesses 5'-3' exonuclease activity on nicked or gapped double-stranded DNA, and exhibits RNase H activity. Also involved in replication and repair of rDNA and in repairing mitochondrial DNA.
Cofactor
Note: Binds 2 magnesium ions per subunit. They probably participate in the reaction catalyzed by the enzyme. May bind an additional third magnesium ion after substrate binding.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 34 | Mg2+ 1 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 71 | DNA (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 87 | Mg2+ 1 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 159 | DNA (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 159 | Mg2+ 1 (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 161 | Mg2+ 1 (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 180 | Mg2+ 2 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 182 | Mg2+ 2 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 232 | DNA (UniProtKB | ChEBI) | ||||
Sequence: G | ||||||
Binding site | 234 | DNA (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 234 | Mg2+ 2 (UniProtKB | ChEBI) | ||||
Sequence: D |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | mitochondrion | |
Cellular Component | nucleolus | |
Cellular Component | nucleoplasm | |
Molecular Function | 5'-3' exonuclease activity | |
Molecular Function | 5'-flap endonuclease activity | |
Molecular Function | DNA binding | |
Molecular Function | magnesium ion binding | |
Biological Process | base-excision repair | |
Biological Process | DNA replication, removal of RNA primer |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameFlap endonuclease 1
- EC number
- Short namesFEN-1
- Alternative names
Gene names
Organism names
- Organism
- Strain
- Taxonomic lineageEukaryota > Viridiplantae > Chlorophyta > Mamiellophyceae > Mamiellales > Bathycoccaceae > Ostreococcus
Accessions
- Primary accessionQ013G9
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Note: Resides mostly in the nucleoli and relocalizes to the nucleoplasm upon DNA damage.
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000403525 | 1-389 | Flap endonuclease 1 | |||
Sequence: MGIKGLTALLSENAPGAMREQKFTSYLDRRVAIDASMHIYQFMIAVGRTGEQTLTNEAGEVTSHLQGMLMRTSRMLEAGIKPVYVFDGKPPTMKGGELAKRKDKREEAEAALKAAREAGNQEEVEKLSKRTVRVSKEQSMEVMKLAQLLGIPAFEAPCEAEATCAAMCKAGLVWAVGTEDMDTLTFAAPRVARNLMAPKSAEKPVLEFDYEKTIAGLGLTADQFIDLCILCGCDYTDTIRGVGPKTALKLIKEHGSIEKILEAIDTEKYPPPKDWEFAGARELFKNPEVMDVSGINLSWKAPDEEGLVEFLVKEKQFQEDRVRGVCARIRKARQGAASQNRLESFFGPPKIISSTIGKRKVEETKSGKGSKAGLNKKSKGVSGYKSKKT |
Post-translational modification
Phosphorylated. Phosphorylation upon DNA damage induces relocalization to the nuclear plasma.
Keywords
- PTM
Interaction
Subunit
Interacts with PCNA. Three molecules of FEN1 bind to one PCNA trimer with each molecule binding to one PCNA monomer. PCNA stimulates the nuclease activity without altering cleavage specificity.
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for region, compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-105 | N-domain | ||||
Sequence: MGIKGLTALLSENAPGAMREQKFTSYLDRRVAIDASMHIYQFMIAVGRTGEQTLTNEAGEVTSHLQGMLMRTSRMLEAGIKPVYVFDGKPPTMKGGELAKRKDKR | ||||||
Region | 123-254 | I-domain | ||||
Sequence: EVEKLSKRTVRVSKEQSMEVMKLAQLLGIPAFEAPCEAEATCAAMCKAGLVWAVGTEDMDTLTFAAPRVARNLMAPKSAEKPVLEFDYEKTIAGLGLTADQFIDLCILCGCDYTDTIRGVGPKTALKLIKEH | ||||||
Region | 338-346 | Interaction with PCNA | ||||
Sequence: SQNRLESFF | ||||||
Compositional bias | 356-370 | Basic and acidic residues | ||||
Sequence: IGKRKVEETKSGKGS | ||||||
Region | 356-389 | Disordered | ||||
Sequence: IGKRKVEETKSGKGSKAGLNKKSKGVSGYKSKKT |
Sequence similarities
Belongs to the XPG/RAD2 endonuclease family. FEN1 subfamily.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length389
- Mass (Da)42,703
- Last updated2011-01-11 v2
- Checksum6C9FA88539120937
Features
Showing features for compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 356-370 | Basic and acidic residues | ||||
Sequence: IGKRKVEETKSGKGS |
Keywords
- Technical term