1i9t: Difference between revisions
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< | ==CRYSTAL STRUCTURE OF THE OXIDIZED RNA TRIPHOSPHATASE DOMAIN OF MOUSE MRNA CAPPING ENZYME== | ||
<StructureSection load='1i9t' size='340' side='right'caption='[[1i9t]], [[Resolution|resolution]] 1.70Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1i9t]] is a 1 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=1I9T OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1I9T FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.7Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CAC:CACODYLATE+ION'>CAC</scene>, <scene name='pdbligand=CSO:S-HYDROXYCYSTEINE'>CSO</scene>, <scene name='pdbligand=IPA:ISOPROPYL+ALCOHOL'>IPA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1i9t FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i9t OCA], [https://pdbe.org/1i9t PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1i9t RCSB], [https://www.ebi.ac.uk/pdbsum/1i9t PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1i9t ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/MCE1_MOUSE MCE1_MOUSE] Bifunctional mRNA-capping enzyme exhibiting RNA 5'-triphosphatase activity in the N-terminal part and mRNA guanylyltransferase activity in the C-terminal part. Catalyzes the first two steps of cap formation: by removing the gamma-phosphate from the 5'-triphosphate end of nascent mRNA to yield a diphosphate end, and by transferring the gmp moiety of GTP to the 5'-diphosphate terminus. | |||
== Evolutionary Conservation == | |||
== | [[Image:Consurf_key_small.gif|200px|right]] | ||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/i9/1i9t_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</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=1i9t ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The 5' capping of mammalian pre-mRNAs is initiated by RNA triphosphatase, a member of the cysteine phosphatase superfamily. Here we report the 1.65 A crystal structure of mouse RNA triphosphatase, which reveals a deep, positively charged active site pocket that can fit a 5' triphosphate end. Structural, biochemical and mutational results show that despite sharing an HCxxxxxR(S/T) motif, a phosphoenzyme intermediate and a core alpha/beta-fold with other cysteine phosphatases, the mechanism of phosphoanhydride cleavage by mammalian capping enzyme differs from that used by protein phosphatases to hydrolyze phosphomonoesters. The most significant difference is the absence of a carboxylate general acid catalyst in RNA triphosphatase. Residues conserved uniquely among the RNA phosphatase subfamily are important for function in cap formation and are likely to play a role in substrate recognition. | The 5' capping of mammalian pre-mRNAs is initiated by RNA triphosphatase, a member of the cysteine phosphatase superfamily. Here we report the 1.65 A crystal structure of mouse RNA triphosphatase, which reveals a deep, positively charged active site pocket that can fit a 5' triphosphate end. Structural, biochemical and mutational results show that despite sharing an HCxxxxxR(S/T) motif, a phosphoenzyme intermediate and a core alpha/beta-fold with other cysteine phosphatases, the mechanism of phosphoanhydride cleavage by mammalian capping enzyme differs from that used by protein phosphatases to hydrolyze phosphomonoesters. The most significant difference is the absence of a carboxylate general acid catalyst in RNA triphosphatase. Residues conserved uniquely among the RNA phosphatase subfamily are important for function in cap formation and are likely to play a role in substrate recognition. | ||
Structure and mechanism of the RNA triphosphatase component of mammalian mRNA capping enzyme.,Changela A, Ho CK, Martins A, Shuman S, Mondragon A EMBO J. 2001 May 15;20(10):2575-86. PMID:11350947<ref>PMID:11350947</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1i9t" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Changela A]] | |||
[[Category: Ho CK]] | |||
[[Category: Changela | [[Category: Martins A]] | ||
[[Category: Ho | [[Category: Mondragon A]] | ||
[[Category: Martins | [[Category: Shuman S]] | ||
[[Category: Mondragon | |||
[[Category: Shuman | |||