| Structural highlights
5twp is a 4 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , , |
| Related: | 5tws, 5twr, 5twq |
| Activity: | DNA-directed DNA polymerase, with EC number 2.7.7.7 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[DPOLM_HUMAN] Gap-filling polymerase involved in repair of DNA double-strand breaks by non-homologous end joining (NHEJ). Participates in immunoglobulin (Ig) light chain gene rearrangement in V(D)J recombination.[1] [2] [3] [4]
Publication Abstract from PubMed
While most DNA polymerases discriminate against ribonucleotide triphosphate (rNTP) incorporation very effectively, the Family X member DNA polymerase mu (Pol mu) incorporates rNTPs almost as efficiently as deoxyribonucleotides. To gain insight into how this occurs, here we have used X-ray crystallography to describe the structures of pre- and post-catalytic complexes of Pol mu with a ribonucleotide bound at the active site. These structures reveal that Pol mu binds and incorporates a rNTP with normal active site geometry and no distortion of the DNA substrate or nucleotide. Moreover, a comparison of rNTP incorporation kinetics by wildtype and mutant Pol mu indicates that rNTP accommodation involves synergistic interactions with multiple active site residues not found in polymerases with greater discrimination. Together, the results are consistent with the hypothesis that rNTP incorporation by Pol mu is advantageous in gap-filling synthesis during DNA double strand break repair by nonhomologous end joining, particularly in nonreplicating cells containing very low deoxyribonucleotide concentrations.
Structural accommodation of ribonucleotide incorporation by the DNA repair enzyme polymerase Mu.,Moon AF, Pryor JM, Ramsden DA, Kunkel TA, Bebenek K, Pedersen LC Nucleic Acids Res. 2017 Sep 6;45(15):9138-9148. doi: 10.1093/nar/gkx527. PMID:28911097[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Nick McElhinny SA, Ramsden DA. Polymerase mu is a DNA-directed DNA/RNA polymerase. Mol Cell Biol. 2003 Apr;23(7):2309-15. PMID:12640116
- ↑ Ruiz JF, Juarez R, Garcia-Diaz M, Terrados G, Picher AJ, Gonzalez-Barrera S, Fernandez de Henestrosa AR, Blanco L. Lack of sugar discrimination by human Pol mu requires a single glycine residue. Nucleic Acids Res. 2003 Aug 1;31(15):4441-9. PMID:12888504
- ↑ Capp JP, Boudsocq F, Besnard AG, Lopez BS, Cazaux C, Hoffmann JS, Canitrot Y. Involvement of DNA polymerase mu in the repair of a specific subset of DNA double-strand breaks in mammalian cells. Nucleic Acids Res. 2007;35(11):3551-60. Epub 2007 May 5. PMID:17483519 doi:http://dx.doi.org/10.1093/nar/gkm243
- ↑ DeRose EF, Clarkson MW, Gilmore SA, Galban CJ, Tripathy A, Havener JM, Mueller GA, Ramsden DA, London RE, Lee AL. Solution structure of polymerase mu's BRCT Domain reveals an element essential for its role in nonhomologous end joining. Biochemistry. 2007 Oct 30;46(43):12100-10. Epub 2007 Oct 4. PMID:17915942 doi:10.1021/bi7007728
- ↑ Moon AF, Pryor JM, Ramsden DA, Kunkel TA, Bebenek K, Pedersen LC. Structural accommodation of ribonucleotide incorporation by the DNA repair enzyme polymerase Mu. Nucleic Acids Res. 2017 Sep 6;45(15):9138-9148. doi: 10.1093/nar/gkx527. PMID:28911097 doi:http://dx.doi.org/10.1093/nar/gkx527
|
