Protein
Flap endonuclease 1-B
Organism
Oryza sativa subsp. japonica
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 structurs 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 (By similarity). May be required for cell proliferation.
Similarity
Belongs to the XPG/RAD2 endonuclease family. FEN1 subfamily.
Sequence
MGIKGLTKLLAEHAPGAAVRRRVEDYRGRVVAIDTSLSIYQFLIVVGRKGTEVLTNEAGEVTSHLQGMLNRTVRILEAGIKPVFVFDGEPPDMKKKELAKRSLKRDGSSEDLNRAIEVGDEDLIEKFSKRTVKVTKKHNEDCKRLLSLMGVPVVQAPGEAEAQCAALCENHKVFAIASEDMDSLTFGARRFLRHLTDLSFKRSPVTEFEVSKVLEELGLTMDQFIDLCILSGCDYCENIRGIGGQRALKLIRQHGYIEEVVQNLSQTRYSVPEDWPYQEVRALFKEPNVCTDIPDFLWTPPDEEGLINFLAAENNFSPDRVVKSVEKIKAANDKFSLGRGKLLAPVANLTGSTSTAGKEPKCILGGPGQVMKARSPLQVCKSSSLNFIHDNSKAFMLGRRSGFLRISTYASI