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6n7t

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Revision as of 11:20, 18 December 2019

Structure of bacteriophage T7 E343Q mutant gp4 helicase-primase in complex with ssDNA, dTTP, AC dinucleotide and CTP (form III)

Structural highlights

6n7t is a 7 chain structure with sequence from Bpt7. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
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]

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^[4]

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
↑ 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 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/6n7t"

@@ Line 1: / Line 1: @@
 ==Structure of bacteriophage T7 E343Q mutant gp4 helicase-primase in complex with ssDNA, dTTP, AC dinucleotide and CTP (form III)==
-<StructureSection load='6n7t' size='340' side='right'  caption='[[6n7t]], [[Resolution|resolution]] 3.90&Aring;' scene=''>
+<StructureSection load='6n7t' size='340' side='right'caption='[[6n7t]], [[Resolution|resolution]] 3.90&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[6n7t]] is a 7 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6N7T OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6N7T FirstGlance]. <br>
+<table><tr><td colspan='2'>[[6n7t]] is a 7 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=6N7T OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6N7T 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></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=6n7t FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6n7t OCA], [http://pdbe.org/6n7t PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6n7t RCSB], [http://www.ebi.ac.uk/pdbsum/6n7t PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6n7t ProSAT]</span></td></tr>
@@ Line 22: / Line 22: @@
 __TOC__
 </StructureSection>
+[[Category: Bpt7]]
+[[Category: Large Structures]]
 [[Category: Cui, Y]]
 [[Category: Gao, Y]]

6n7t

From Proteopedia

Revision as of 11:20, 18 December 2019

Structure of bacteriophage T7 E343Q mutant gp4 helicase-primase in complex with ssDNA, dTTP, AC dinucleotide and CTP (form III)

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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