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| - | [[Image:1jk2.gif|left|200px]] | |
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| - | {{Structure
| + | ==Zif268 D20A mutant bound to the GCT DNA site== |
| - | |PDB= 1jk2 |SIZE=350|CAPTION= <scene name='initialview01'>1jk2</scene>, resolution 1.65Å
| + | <StructureSection load='1jk2' size='340' side='right'caption='[[1jk2]], [[Resolution|resolution]] 1.65Å' scene=''> |
| - | |SITE=
| + | == Structural highlights == |
| - | |LIGAND= <scene name='pdbligand=DA:2'-DEOXYADENOSINE-5'-MONOPHOSPHATE'>DA</scene>, <scene name='pdbligand=DC:2'-DEOXYCYTIDINE-5'-MONOPHOSPHATE'>DC</scene>, <scene name='pdbligand=DG:2'-DEOXYGUANOSINE-5'-MONOPHOSPHATE'>DG</scene>, <scene name='pdbligand=DT:THYMIDINE-5'-MONOPHOSPHATE'>DT</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene>
| + | <table><tr><td colspan='2'>[[1jk2]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JK2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1JK2 FirstGlance]. <br> |
| - | |ACTIVITY=
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.65Å</td></tr> |
| - | |GENE=
| + | <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> |
| - | |DOMAIN=
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1jk2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jk2 OCA], [https://pdbe.org/1jk2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1jk2 RCSB], [https://www.ebi.ac.uk/pdbsum/1jk2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1jk2 ProSAT]</span></td></tr> |
| - | |RELATEDENTRY=[[1aay|1AAY]], [[1jk1|1JK1]]
| + | </table> |
| - | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jk2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jk2 OCA], [http://www.ebi.ac.uk/pdbsum/1jk2 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1jk2 RCSB]</span>
| + | == Function == |
| - | }}
| + | [https://www.uniprot.org/uniprot/EGR1_MOUSE EGR1_MOUSE] Transcriptional regulator. Recognizes and binds to the DNA sequence 5'-CGCCCCCGC-3'(EGR-site). Activates the transcription of target genes whose products are required for mitogenesis and differentiation. |
| - | | + | == Evolutionary Conservation == |
| - | '''Zif268 D20A mutant bound to the GCT DNA site'''
| + | [[Image:Consurf_key_small.gif|200px|right]] |
| - | | + | Check<jmol> |
| - | | + | <jmolCheckbox> |
| - | ==Overview== | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/jk/1jk2_consurf.spt"</scriptWhenChecked> |
| - | Structural and biochemical studies of Cys(2)His(2) zinc finger proteins initially led several groups to propose a "recognition code" involving a simple set of rules relating key amino acid residues in the zinc finger protein to bases in its DNA site. One recent study from our group, involving geometric analysis of protein-DNA interactions, has discussed limitations of this idea and has shown how the spatial relationship between the polypeptide backbone and the DNA helps to determine what contacts are possible at any given position in a protein-DNA complex. Here we report a study of a zinc finger variant that highlights yet another source of complexity inherent in protein-DNA recognition. In particular, we find that mutations can cause key side-chains to rearrange at the protein-DNA interface without fundamental changes in the spatial relationship between the polypeptide backbone and the DNA. This is clear from a simple analysis of the binding site preferences and co-crystal structures for the Asp20-->Ala point mutant of Zif268. This point mutation in finger one changes the specificity of the protein from GCG TGG GCG to GCG TGG GC(G/T), and we have solved crystal structures of the D20A mutant bound to both types of sites. The structure of the D20A mutant bound to the GCG site reveals that contacts from key residues in the recognition helix are coupled in complex ways. The structure of the complex with the GCT site also shows an important new water molecule at the protein-DNA interface. These side-chain/side-chain interactions, and resultant changes in hydration at the interface, affect binding specificity in ways that cannot be predicted either from a simple recognition code or from analysis of spatial relationships at the protein-DNA interface. Accurate computer modeling of protein-DNA interfaces remains a challenging problem and will require systematic strategies for modeling side-chain rearrangements and change in hydration.
| + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| - | | + | <text>to colour the structure by Evolutionary Conservation</text> |
| - | ==About this Structure== | + | </jmolCheckbox> |
| - | 1JK2 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JK2 OCA].
| + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1jk2 ConSurf]. |
| - | | + | <div style="clear:both"></div> |
| - | ==Reference==
| + | __TOC__ |
| - | Rearrangement of side-chains in a Zif268 mutant highlights the complexities of zinc finger-DNA recognition., Miller JC, Pabo CO, J Mol Biol. 2001 Oct 19;313(2):309-15. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11800559 11800559]
| + | </StructureSection> |
| | + | [[Category: Large Structures]] |
| | [[Category: Mus musculus]] | | [[Category: Mus musculus]] |
| - | [[Category: Single protein]]
| + | [[Category: Miller JC]] |
| - | [[Category: Miller, J C.]] | + | [[Category: Pabo CO]] |
| - | [[Category: Pabo, C O.]] | + | |
| - | [[Category: double stranded dna]]
| + | |
| - | [[Category: protein-dna complex]]
| + | |
| - | [[Category: zinc-finger]]
| + | |
| - | | + | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:34:45 2008''
| + | |
