Structural highlights
4f5p is a 4 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | , , |
| Related: | 4f5n, 4f5o, 4f5q, 4f5r |
| Gene: | POLB (HUMAN) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[DPOLB_HUMAN] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.[1] [2] [3] [4]
Publication Abstract from PubMed
DNA polymerase and substrate conformational changes are essential for high-fidelity DNA synthesis. Structures of DNA polymerase (pol) beta in complex with DNA show the enzyme in an "open" conformation. Subsequent to binding the nucleotide, the polymerase "closes" around the nascent base pair with two metals positioned for chemistry. However, structures of substrate/active site intermediates prior to closure are lacking. By destabilizing the closed complex, we determined unique ternary complex structures of pol beta with correct and incorrect incoming nucleotides bound to the open conformation. These structures reveal that Watson-Crick hydrogen bonding is assessed upon initial complex formation. Importantly, nucleotide-bound states representing intermediate metal coordination states occur with active site assembly. The correct, but not incorrect, nucleotide maintains Watson-Crick hydrogen bonds during interconversion of these states. These structures indicate that the triphosphate of the incoming nucleotide undergoes rearrangement prior to closure, providing an opportunity to deter misinsertion and increase fidelity.
Structures of dNTP Intermediate States during DNA Polymerase Active Site Assembly.,Freudenthal BD, Beard WA, Wilson SH Structure. 2012 Nov 7;20(11):1829-37. doi: 10.1016/j.str.2012.08.008. Epub 2012, Sep 6. PMID:22959623[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Bennett RA, Wilson DM 3rd, Wong D, Demple B. Interaction of human apurinic endonuclease and DNA polymerase beta in the base excision repair pathway. Proc Natl Acad Sci U S A. 1997 Jul 8;94(14):7166-9. PMID:9207062
- ↑ Matsumoto Y, Kim K, Katz DS, Feng JA. Catalytic center of DNA polymerase beta for excision of deoxyribose phosphate groups. Biochemistry. 1998 May 5;37(18):6456-64. PMID:9572863 doi:10.1021/bi9727545
- ↑ DeMott MS, Beyret E, Wong D, Bales BC, Hwang JT, Greenberg MM, Demple B. Covalent trapping of human DNA polymerase beta by the oxidative DNA lesion 2-deoxyribonolactone. J Biol Chem. 2002 Mar 8;277(10):7637-40. Epub 2002 Jan 22. PMID:11805079 doi:10.1074/jbc.C100577200
- ↑ Parsons JL, Dianova II, Khoronenkova SV, Edelmann MJ, Kessler BM, Dianov GL. USP47 is a deubiquitylating enzyme that regulates base excision repair by controlling steady-state levels of DNA polymerase beta. Mol Cell. 2011 Mar 4;41(5):609-15. doi: 10.1016/j.molcel.2011.02.016. PMID:21362556 doi:10.1016/j.molcel.2011.02.016
- ↑ Freudenthal BD, Beard WA, Wilson SH. Structures of dNTP Intermediate States during DNA Polymerase Active Site Assembly. Structure. 2012 Nov 7;20(11):1829-37. doi: 10.1016/j.str.2012.08.008. Epub 2012, Sep 6. PMID:22959623 doi:http://dx.doi.org/10.1016/j.str.2012.08.008
