View source for 3lbh


==Ras soaked in Calcium Acetate==
<StructureSection load='3lbh' size='340' side='right'caption='[[3lbh]], [[Resolution|resolution]] 1.85&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3lbh]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LBH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3LBH 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]] 1.85&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=GNP:PHOSPHOAMINOPHOSPHONIC+ACID-GUANYLATE+ESTER'>GNP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=3lbh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3lbh OCA], [https://pdbe.org/3lbh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3lbh RCSB], [https://www.ebi.ac.uk/pdbsum/3lbh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3lbh ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/RASH_HUMAN RASH_HUMAN] Defects in HRAS are the cause of faciocutaneoskeletal syndrome (FCSS) [MIM:[https://omim.org/entry/218040 218040]. A rare condition characterized by prenatally increased growth, postnatal growth deficiency, mental retardation, distinctive facial appearance, cardiovascular abnormalities (typically pulmonic stenosis, hypertrophic cardiomyopathy and/or atrial tachycardia), tumor predisposition, skin and musculoskeletal abnormalities.<ref>PMID:16170316</ref> <ref>PMID:16329078</ref> <ref>PMID:16443854</ref> <ref>PMID:17054105</ref> <ref>PMID:18247425</ref> <ref>PMID:18039947</ref> <ref>PMID:19995790</ref>   Defects in HRAS are the cause of congenital myopathy with excess of muscle spindles (CMEMS) [MIM:[https://omim.org/entry/218040 218040]. CMEMS is a variant of Costello syndrome.<ref>PMID:17412879</ref>   Defects in HRAS may be a cause of susceptibility to Hurthle cell thyroid carcinoma (HCTC) [MIM:[https://omim.org/entry/607464 607464]. Hurthle cell thyroid carcinoma accounts for approximately 3% of all thyroid cancers. Although they are classified as variants of follicular neoplasms, they are more often multifocal and somewhat more aggressive and are less likely to take up iodine than are other follicular neoplasms.  Note=Mutations which change positions 12, 13 or 61 activate the potential of HRAS to transform cultured cells and are implicated in a variety of human tumors.  Defects in HRAS are a cause of susceptibility to bladder cancer (BLC) [MIM:[https://omim.org/entry/109800 109800]. A malignancy originating in tissues of the urinary bladder. It often presents with multiple tumors appearing at different times and at different sites in the bladder. Most bladder cancers are transitional cell carcinomas. They begin in cells that normally make up the inner lining of the bladder. Other types of bladder cancer include squamous cell carcinoma (cancer that begins in thin, flat cells) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids). Bladder cancer is a complex disorder with both genetic and environmental influences.  Note=Defects in HRAS are the cause of oral squamous cell carcinoma (OSCC).<ref>PMID:1459726</ref>   Defects in HRAS are the cause of Schimmelpenning-Feuerstein-Mims syndrome (SFM) [MIM:[https://omim.org/entry/163200 163200]. A disease characterized by sebaceous nevi, often on the face, associated with variable ipsilateral abnormalities of the central nervous system, ocular anomalies, and skeletal defects. Many oral manifestations have been reported, not only including hypoplastic and malformed teeth, and mucosal papillomatosis, but also ankyloglossia, hemihyperplastic tongue, intraoral nevus, giant cell granuloma, ameloblastoma, bone cysts, follicular cysts, oligodontia, and odontodysplasia. Sebaceous nevi follow the lines of Blaschko and these can continue as linear intraoral lesions, as in mucosal papillomatosis.<ref>PMID:22683711</ref> 
== Function ==
[https://www.uniprot.org/uniprot/RASH_HUMAN RASH_HUMAN] Ras proteins bind GDP/GTP and possess intrinsic GTPase activity.<ref>PMID:14500341</ref> <ref>PMID:9020151</ref> <ref>PMID:12740440</ref> 
== 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/lb/3lbh_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=3lbh ConSurf].
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== Publication Abstract from PubMed ==
Ras and its effector Raf are key mediators of the Ras/Raf/MEK/ERK signal transduction pathway. Mutants of residue Q61 impair the GTPase activity of Ras and are found prominently in human cancers. Yet the mechanism through which Q61 contributes to catalysis has been elusive. It is thought to position the catalytic water molecule for nucleophilic attack on the gamma-phosphate of GTP. However, we previously solved the structure of Ras from crystals with symmetry of the space group R32 in which switch II is disordered and found that the catalytic water molecule is present. Here we present a structure of wild-type Ras with calcium acetate from the crystallization mother liquor bound at a site remote from the active site and likely near the membrane. This results in a shift in helix 3/loop 7 and a network of H-bonding interactions that propagates across the molecule, culminating in the ordering of switch II and placement of Q61 in the active site in a previously unobserved conformation. This structure suggests a direct catalytic role for Q61 where it interacts with a water molecule that bridges one of the gamma-phosphate oxygen atoms to the hydroxyl group of Y32 to stabilize the transition state of the hydrolysis reaction. We propose that Raf together with the binding of Ca(2+) and a negatively charged group mimicked in our structure by the acetate molecule induces the ordering of switch I and switch II to complete the active site of Ras.

Allosteric modulation of Ras positions Q61 for a direct role in catalysis.,Buhrman G, Holzapfel G, Fetics S, Mattos C Proc Natl Acad Sci U S A. 2010 Mar 16;107(11):4931-6. Epub 2010 Mar 1. PMID:20194776<ref>PMID:20194776</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3lbh" style="background-color:#fffaf0;"></div>

==See Also==
*[[GTPase Hras 3D structures|GTPase Hras 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Buhrman G]]
[[Category: Holzapfel G]]
[[Category: Mattos C]]