5fhh

From Proteopedia
Jump to navigation Jump to search

Structure of human Pif1 helicase domain residues 200-641Structure of human Pif1 helicase domain residues 200-641

Structural highlights

5fhh is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 3.6Å
Ligands:,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

PIF1_HUMAN DNA-dependent ATPase and 5'-3' DNA helicase required for the maintenance of both mitochondrial and nuclear genome stability. Efficiently unwinds G-quadruplex (G4) DNA structures and forked RNA-DNA hybrids. Resolves G4 structures, preventing replication pausing and double-strand breaks (DSBs) at G4 motifs. Involved in the maintenance of telomeric DNA. Inhibits telomere elongation, de novo telomere formation and telomere addition to DSBs via catalytic inhibition of telomerase. Reduces the processivity of telomerase by displacing active telomerase from DNA ends. Releases telomerase by unwinding the short telomerase RNA/telomeric DNA hybrid that is the intermediate in the telomerase reaction. Possesses an intrinsic strand annealing activity.[HAMAP-Rule:MF_03176][1] [2] [3] [4] [5] [6] [7]

Publication Abstract from PubMed

Pif1 is a conserved SF1B DNA helicase involved in maintaining genome stability through unwinding double-stranded DNAs (dsDNAs), DNA/RNA hybrids, and G quadruplex (G4) structures. Here, we report the structures of the helicase domain of human Pif1 and Bacteroides sp Pif1 (BaPif1) in complex with ADP-AlF4(-) and two different single-stranded DNAs (ssDNAs). The wedge region equivalent to the beta hairpin in other SF1B DNA helicases folds into an extended loop followed by an alpha helix. The Pif1 signature motif of BaPif1 interacts with the wedge region and a short helix in order to stabilize these ssDNA binding elements, therefore indirectly exerting its functional role. Domain 2B of BaPif1 undergoes a large conformational change upon concomitant binding of ATP and ssDNA, which is critical for Pif1's activities. BaPif1 cocrystallized with a tailed dsDNA and ADP-AlF4(-), resulting in a bound ssDNA bent nearly 90 degrees at the ssDNA/dsDNA junction. The conformational snapshots of BaPif1 provide insights into the mechanism governing the helicase activity of Pif1.

Structural and Functional Insights into the Unwinding Mechanism of Bacteroides sp Pif1.,Zhou X, Ren W, Bharath SR, Tang X, He Y, Chen C, Liu Z, Li D, Song H Cell Rep. 2016 Mar 1;14(8):2030-9. doi: 10.1016/j.celrep.2016.02.008. Epub 2016, Feb 18. PMID:26904952[8]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. ↑ Zhang DH, Zhou B, Huang Y, Xu LX, Zhou JQ. The human Pif1 helicase, a potential Escherichia coli RecD homologue, inhibits telomerase activity. Nucleic Acids Res. 2006 Mar 6;34(5):1393-404. Print 2006. PMID:16522649 doi:http://dx.doi.org/34/5/1393
  2. ↑ Mateyak MK, Zakian VA. Human PIF helicase is cell cycle regulated and associates with telomerase. Cell Cycle. 2006 Dec;5(23):2796-804. Epub 2006 Dec 1. PMID:17172855
  3. ↑ Futami K, Shimamoto A, Furuichi Y. Mitochondrial and nuclear localization of human Pif1 helicase. Biol Pharm Bull. 2007 Sep;30(9):1685-92. PMID:17827721
  4. ↑ Gu Y, Masuda Y, Kamiya K. Biochemical analysis of human PIF1 helicase and functions of its N-terminal domain. Nucleic Acids Res. 2008 Nov;36(19):6295-308. doi: 10.1093/nar/gkn609. Epub 2008, Oct 3. PMID:18835853 doi:http://dx.doi.org/10.1093/nar/gkn609
  5. ↑ George T, Wen Q, Griffiths R, Ganesh A, Meuth M, Sanders CM. Human Pif1 helicase unwinds synthetic DNA structures resembling stalled DNA replication forks. Nucleic Acids Res. 2009 Oct;37(19):6491-502. doi: 10.1093/nar/gkp671. Epub 2009, Aug 21. PMID:19700773 doi:http://dx.doi.org/10.1093/nar/gkp671
  6. ↑ Sanders CM. Human Pif1 helicase is a G-quadruplex DNA-binding protein with G-quadruplex DNA-unwinding activity. Biochem J. 2010 Aug 15;430(1):119-28. doi: 10.1042/BJ20100612. PMID:20524933 doi:http://dx.doi.org/10.1042/BJ20100612
  7. ↑ Paeschke K, Bochman ML, Garcia PD, Cejka P, Friedman KL, Kowalczykowski SC, Zakian VA. Pif1 family helicases suppress genome instability at G-quadruplex motifs. Nature. 2013 May 23;497(7450):458-62. doi: 10.1038/nature12149. Epub 2013 May 8. PMID:23657261 doi:http://dx.doi.org/10.1038/nature12149
  8. ↑ Zhou X, Ren W, Bharath SR, Tang X, He Y, Chen C, Liu Z, Li D, Song H. Structural and Functional Insights into the Unwinding Mechanism of Bacteroides sp Pif1. Cell Rep. 2016 Mar 1;14(8):2030-9. doi: 10.1016/j.celrep.2016.02.008. Epub 2016, Feb 18. PMID:26904952 doi:http://dx.doi.org/10.1016/j.celrep.2016.02.008

5fhh, resolution 3.60Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA
Retrieved from "https://proteopedia.openfox.io/wiki/index.php?title=5fhh&oldid=3808090"