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6n9x

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Structure of bacteriophage T7 lagging-strand DNA polymerase (D5A/E7A) and gp4 (helicase/primase) bound to DNA including RNA/DNA hybrid, and an incoming dTTP (LagS3)

6n9x, resolution 4.10Å

Structural highlights

6n9x is a 9 chain structure with sequence from Bpt7. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Related:	6n7i, 6n7n, 6n7s, 6n7t, 6n7v, 6n7w, 6n9u, 6n9v, 6n9w
Experimental data:	Check to display Experimental Data
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[PRIM_BPT7] Synthesizes short RNA primers for DNA replication. Unwinds the DNA at the replication forks and generates single-stranded DNA for both leading and lagging strand synthesis. The primase synthesizes short RNA primers on the lagging strand that the polymerase elongates using dNTPs.^[1] ^[2] ^[3] [DPOL_BPT7] Replicates viral genomic DNA. Non-processive DNA polymerase that achieves processivity by binding to host thioredoxin (TrxA). This interaction increases the rate of dNTP incorporation to yield a processivity of approximately 800 nucleotides (nt) per binding event. Interacts with DNA helicase gp4 to coordinate nucleotide polymerization with unwinding of the DNA. The leading strand is synthesized continuously while synthesis of the lagging strand requires the synthesis of oligoribonucleotides by the primase domain of gp4.^[4] ^[5]

Publication Abstract from PubMed

Visualization in atomic detail of the replisome that performs concerted leading- and lagging-DNA strand synthesis at a replication fork has not been reported. Using bacteriophage T7 as a model system, we determined cryo-electron microscopy structures up to 3.2-angstroms resolution of helicase translocating along DNA and of helicase-polymerase-primase complexes engaging in synthesis of both DNA strands. Each domain of the spiral-shaped hexameric helicase translocates sequentially hand-over-hand along a single-stranded DNA coil, akin to the way AAA+ ATPases (adenosine triphosphatases) unfold peptides. Two lagging-strand polymerases are attached to the primase, ready for Okazaki fragment synthesis in tandem. A beta hairpin from the leading-strand polymerase separates two parental DNA strands into a T-shaped fork, thus enabling the closely coupled helicase to advance perpendicular to the downstream DNA duplex. These structures reveal the molecular organization and operating principles of a replisome.

Structures and operating principles of the replisome.,Gao Y, Cui Y, Fox T, Lin S, Wang H, de Val N, Zhou ZH, Yang W Science. 2019 Feb 22;363(6429). pii: science.aav7003. doi:, 10.1126/science.aav7003. Epub 2019 Jan 24. PMID:30679383^[6]

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

References

↑ Kong D, Griffith JD, Richardson CC. Gene 4 helicase of bacteriophage T7 mediates strand transfer through pyrimidine dimers, mismatches, and nonhomologous regions. Proc Natl Acad Sci U S A. 1997 Apr 1;94(7):2987-92. PMID:9096333
↑ Zhang H, Lee SJ, Zhu B, Tran NQ, Tabor S, Richardson CC. Helicase-DNA polymerase interaction is critical to initiate leading-strand DNA synthesis. Proc Natl Acad Sci U S A. 2011 Jun 7;108(23):9372-7. doi:, 10.1073/pnas.1106678108. Epub 2011 May 23. PMID:21606333 doi:http://dx.doi.org/10.1073/pnas.1106678108
↑ Kulczyk AW, Akabayov B, Lee SJ, Bostina M, Berkowitz SA, Richardson CC. An interaction between DNA polymerase and helicase is essential for the high processivity of the bacteriophage T7 replisome. J Biol Chem. 2012 Nov 9;287(46):39050-60. doi: 10.1074/jbc.M112.410647. Epub 2012, Sep 12. PMID:22977246 doi:http://dx.doi.org/10.1074/jbc.M112.410647
↑ Notarnicola SM, Mulcahy HL, Lee J, Richardson CC. The acidic carboxyl terminus of the bacteriophage T7 gene 4 helicase/primase interacts with T7 DNA polymerase. J Biol Chem. 1997 Jul 18;272(29):18425-33. PMID:9218486
↑ Zhang H, Lee SJ, Zhu B, Tran NQ, Tabor S, Richardson CC. Helicase-DNA polymerase interaction is critical to initiate leading-strand DNA synthesis. Proc Natl Acad Sci U S A. 2011 Jun 7;108(23):9372-7. doi:, 10.1073/pnas.1106678108. Epub 2011 May 23. PMID:21606333 doi:http://dx.doi.org/10.1073/pnas.1106678108
↑ Gao Y, Cui Y, Fox T, Lin S, Wang H, de Val N, Zhou ZH, Yang W. Structures and operating principles of the replisome. Science. 2019 Feb 22;363(6429). pii: science.aav7003. doi:, 10.1126/science.aav7003. Epub 2019 Jan 24. PMID:30679383 doi:http://dx.doi.org/10.1126/science.aav7003

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/6n9x"

@@ Line 3: / Line 3: @@
 <SX load='6n9x' size='340' side='right' viewer='molstar' caption='[[6n9x]], [[Resolution|resolution]] 4.10&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[6n9x]] is a 9 chain structure with sequence from [http://en.wikipedia.org/wiki/Bpt7 Bpt7]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6N9X OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6N9X FirstGlance]. <br>
+<table><tr><td colspan='2'>[[6n9x]] is a 9 chain structure with sequence from [http://en.wikipedia.org/wiki/Bpt7 Bpt7]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6N9X OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=6N9X 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>, <scene name='pdbligand=TTP:THYMIDINE-5-TRIPHOSPHATE'>TTP</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=TTP:THYMIDINE-5-TRIPHOSPHATE'>TTP</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
 <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[6n7i|6n7i]], [[6n7n|6n7n]], [[6n7s|6n7s]], [[6n7t|6n7t]], [[6n7v|6n7v]], [[6n7w|6n7w]], [[6n9u|6n9u]], [[6n9v|6n9v]], [[6n9w|6n9w]]</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=6n9x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6n9x OCA], [http://pdbe.org/6n9x PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6n9x RCSB], [http://www.ebi.ac.uk/pdbsum/6n9x PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6n9x ProSAT]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=6n9x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6n9x OCA], [http://pdbe.org/6n9x PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6n9x RCSB], [http://www.ebi.ac.uk/pdbsum/6n9x PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6n9x ProSAT]</span></td></tr>
 </table>
 == Function ==

6n9x

From Proteopedia

Current revision

Structure of bacteriophage T7 lagging-strand DNA polymerase (D5A/E7A) and gp4 (helicase/primase) bound to DNA including RNA/DNA hybrid, and an incoming dTTP (LagS3)

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

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