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1a74

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(New page: 200px<br /><applet load="1a74" size="450" color="white" frame="true" align="right" spinBox="true" caption="1a74, resolution 2.200&Aring;" /> '''I-PPOL HOMING ENDON...)
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[[Image:1a74.jpg|left|200px]]<br /><applet load="1a74" size="450" color="white" frame="true" align="right" spinBox="true"
 
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caption="1a74, resolution 2.200&Aring;" />
 
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'''I-PPOL HOMING ENDONUCLEASE/DNA COMPLEX'''<br />
 
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==Overview==
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==I-PPOL HOMING ENDONUCLEASE/DNA COMPLEX==
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Homing endonucleases are a diverse collection of proteins that are encoded, by genes with mobile, self-splicing introns. They have also been, identified in self-splicing inteins (protein introns). These enzymes, promote the movement of the DNA sequences that encode them from one, chromosome location to another; they do this by making a site-specific, double-strand break at a target site in an allele that lacks the, corresponding mobile intron. The target sites recognized by these small, endonucleases are generally long (14-44 base pairs). Four families of, homing endonucleases have been identified, including the LAGLIDADG, the, His-Cys box, the GIY-YIG and the H-N-H endonucleases. The first identified, His-Cys box homing endonuclease was I-PpoI from the slime mould Physarum, polycephalum. Its gene resides in one of only a few nuclear introns known, to exhibit genetic mobility. Here we report the structure of the I-PpoI, homing endonuclease bound to homing-site DNA determined to 1.8 A, resolution. I-PpoI displays an elongated fold of dimensions 25 x 35 x 80, A, with mixed alpha/beta topology. Each I-PpoI monomer contains three, antiparallel beta-sheets flanked by two long alpha-helices and a long, carboxy-terminal tail, and is stabilized by two bound zinc ions 15 A, apart. The enzyme possesses a new zinc-bound fold and endonuclease active, site. The structure has been determined in both uncleaved substrate and, cleaved product complexes.
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<StructureSection load='1a74' size='340' side='right'caption='[[1a74]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
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== Structural highlights ==
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<table><tr><td colspan='2'>[[1a74]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Physarum_polycephalum Physarum polycephalum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A74 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1A74 FirstGlance]. <br>
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</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.2&#8491;</td></tr>
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<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
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<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1a74 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1a74 OCA], [https://pdbe.org/1a74 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1a74 RCSB], [https://www.ebi.ac.uk/pdbsum/1a74 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1a74 ProSAT]</span></td></tr>
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</table>
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== Function ==
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[https://www.uniprot.org/uniprot/PPO1_PHYPO PPO1_PHYPO] Mediates the homing of a group I intron in the ribosomal DNA. Makes a four-base staggered cut in its ribosomal DNA target sequence.
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==About this Structure==
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==See Also==
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1A74 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Physarum_polycephalum Physarum polycephalum] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1A74 OCA].
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*[[Endonuclease 3D structures|Endonuclease 3D structures]]
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__TOC__
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==Reference==
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</StructureSection>
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DNA binding and cleavage by the nuclear intron-encoded homing endonuclease I-PpoI., Flick KE, Jurica MS, Monnat RJ Jr, Stoddard BL, Nature. 1998 Jul 2;394(6688):96-101. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9665136 9665136]
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[[Category: Large Structures]]
[[Category: Physarum polycephalum]]
[[Category: Physarum polycephalum]]
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[[Category: Single protein]]
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[[Category: Flick KE]]
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[[Category: Flick, K.E.]]
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[[Category: Jurica BL]]
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[[Category: Junior, R.J.Monnat.]]
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[[Category: Monnat Junior RJ]]
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[[Category: Jurica, B.L.]]
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[[Category: Stoddard MS]]
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[[Category: Stoddard, M.S.]]
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[[Category: ZN]]
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[[Category: complex (homing endonuclease/dna)]]
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[[Category: dna binding]]
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[[Category: homing endonuclease]]
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[[Category: intron]]
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[[Category: protein folding]]
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[[Category: zinc finger]]
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''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 10:39:18 2007''
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Current revision

I-PPOL HOMING ENDONUCLEASE/DNA COMPLEX

PDB ID 1a74

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