View source for 1ul1


==Crystal structure of the human FEN1-PCNA complex==
<StructureSection load='1ul1' size='340' side='right'caption='[[1ul1]], [[Resolution|resolution]] 2.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ul1]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. The June 2012 RCSB PDB [http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Sliding Clamps''  by David Goodsell is [http://dx.doi.org/10.2210/rcsb_pdb/mom_2012_6 10.2210/rcsb_pdb/mom_2012_6]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1UL1 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1UL1 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1b43|1b43]], [[1a76|1a76]], [[1axc|1axc]]</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1ul1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ul1 OCA], [http://pdbe.org/1ul1 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1ul1 RCSB], [http://www.ebi.ac.uk/pdbsum/1ul1 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1ul1 ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/FEN1_HUMAN FEN1_HUMAN]] 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.<ref>PMID:7961795</ref> <ref>PMID:8621570</ref> <ref>PMID:10744741</ref> <ref>PMID:11986308</ref> <ref>PMID:18443037</ref> <ref>PMID:20729856</ref>  [[http://www.uniprot.org/uniprot/PCNA_HUMAN PCNA_HUMAN]] Auxiliary protein of DNA polymerase delta and is involved in the control of eukaryotic DNA replication by increasing the polymerase's processibility during elongation of the leading strand. Induces a robust stimulatory effect on the 3'-5' exonuclease and 3'-phosphodiesterase, but not apurinic-apyrimidinic (AP) endonuclease, APEX2 activities. Has to be loaded onto DNA in order to be able to stimulate APEX2. Plays a key role in DNA damage response (DDR) by being conveniently positioned at the replication fork to coordinate DNA replication with DNA repair and DNA damage tolerance pathways. Acts as a loading platform to recruit DDR proteins that allow completion of DNA replication after DNA damage and promote postreplication repair: Monoubiquitinated PCNA leads to recruitment of translesion (TLS) polymerases, while 'Lys-63'-linked polyubiquitination of PCNA is involved in error-free pathway and employs recombination mechanisms to synthesize across the lesion.<ref>PMID:19443450</ref> <ref>PMID:18719106</ref>  
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ul/1ul1_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1ul1 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Flap endonuclease-1 (FEN1) is a key enzyme for maintaining genomic stability and replication. Proliferating cell nuclear antigen (PCNA) binds FEN1 and stimulates its endonuclease activity. The structural basis of the FEN1-PCNA interaction was revealed by the crystal structure of the complex between human FEN1 and PCNA. The main interface involves the C-terminal tail of FEN1, which forms two beta-strands connected by a short helix, the betaA-alphaA-betaB motif, participating in beta-beta and hydrophobic interactions with PCNA. These interactions are similar to those previously observed for the p21CIP1/WAF1 peptide. However, this structure involving the full-length enzyme has revealed additional interfaces that are involved in the core domain. The interactions at the interfaces maintain the enzyme in an inactive 'locked-down' orientation and might be utilized in rapid DNA-tracking by preserving the central hole of PCNA for sliding along the DNA. A hinge region present between the core domain and the C-terminal tail of FEN1 would play a role in switching the FEN1 orientation from an inactive to an active orientation.

Structural basis for recruitment of human flap endonuclease 1 to PCNA.,Sakurai S, Kitano K, Yamaguchi H, Hamada K, Okada K, Fukuda K, Uchida M, Ohtsuka E, Morioka H, Hakoshima T EMBO J. 2005 Feb 23;24(4):683-93. Epub 2004 Dec 16. PMID:15616578<ref>PMID:15616578</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1ul1" style="background-color:#fffaf0;"></div>

==See Also==
*[[Endonuclease 3D structures|Endonuclease 3D structures]]
*[[Proliferating cell nuclear antigen 3D structures|Proliferating cell nuclear antigen 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Large Structures]]
[[Category: RCSB PDB Molecule of the Month]]
[[Category: Sliding Clamps]]
[[Category: Fukuda, K]]
[[Category: Hakoshima, T]]
[[Category: Hamada, K]]
[[Category: Kitano, K]]
[[Category: Morioka, H]]
[[Category: Ohtsuka, E]]
[[Category: Okada, K]]
[[Category: Sakurai, S]]
[[Category: Uchida, M]]
[[Category: Yamaguchi, H]]
[[Category: Dna clamp]]
[[Category: Dna repair]]
[[Category: Dna-binding protein]]
[[Category: Flap dna]]
[[Category: Flap endonuclease]]
[[Category: Hydrolase-dna binding protein complex]]
[[Category: Protein complex]]
[[Category: Replication]]
[[Category: Sliding clamp]]