1srq
From Proteopedia
(New page: 200px<br /> <applet load="1srq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1srq, resolution 2.90Å" /> '''Crystal Structure o...) |
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| - | [[Image:1srq.gif|left|200px]]<br /> | + | [[Image:1srq.gif|left|200px]]<br /><applet load="1srq" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1srq" size=" | + | |
caption="1srq, resolution 2.90Å" /> | caption="1srq, resolution 2.90Å" /> | ||
'''Crystal Structure of the Rap1GAP catalytic domain'''<br /> | '''Crystal Structure of the Rap1GAP catalytic domain'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Rap1 is a Ras-like guanine-nucleotide-binding protein (GNBP) that is | + | Rap1 is a Ras-like guanine-nucleotide-binding protein (GNBP) that is involved in a variety of signal-transduction processes. It regulates integrin-mediated cell adhesion and might activate extracellular signal-regulated kinase. Like other Ras-like GNBPs, Rap1 is regulated by guanine-nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs). These GAPs increase the slow intrinsic GTPase reaction of Ras-like GNBPs by many orders of magnitude and allow tight regulation of signalling. The activation mechanism involves stabilization of the catalytic glutamine of the GNBP and, in most cases, the insertion of a catalytic arginine of GAP into the active site. Rap1 is a close homologue of Ras but does not possess the catalytic glutamine essential for GTP hydrolysis in all other Ras-like and Galpha proteins. Furthermore, RapGAPs are not related to other GAPs and apparently do not use a catalytic arginine residue. Here we present the crystal structure of the catalytic domain of the Rap1-specific Rap1GAP at 2.9 A. By mutational analysis, fluorescence titration and stopped-flow kinetic assay, we demonstrate that Rap1GAP provides a catalytic asparagine to stimulate GTP hydrolysis. Implications for the disease tuberous sclerosis are discussed. |
==About this Structure== | ==About this Structure== | ||
| - | 1SRQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with SO4 and MPD as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1SRQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=MPD:'>MPD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SRQ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Chakrabarti, P | + | [[Category: Chakrabarti, P P.]] |
[[Category: Daumke, O.]] | [[Category: Daumke, O.]] | ||
| - | [[Category: Vetter, I | + | [[Category: Vetter, I R.]] |
[[Category: Weyand, M.]] | [[Category: Weyand, M.]] | ||
[[Category: Wittinghofer, A.]] | [[Category: Wittinghofer, A.]] | ||
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[[Category: mixed alpha-beta]] | [[Category: mixed alpha-beta]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:04:32 2008'' |
Revision as of 13:04, 21 February 2008
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Crystal Structure of the Rap1GAP catalytic domain
Overview
Rap1 is a Ras-like guanine-nucleotide-binding protein (GNBP) that is involved in a variety of signal-transduction processes. It regulates integrin-mediated cell adhesion and might activate extracellular signal-regulated kinase. Like other Ras-like GNBPs, Rap1 is regulated by guanine-nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs). These GAPs increase the slow intrinsic GTPase reaction of Ras-like GNBPs by many orders of magnitude and allow tight regulation of signalling. The activation mechanism involves stabilization of the catalytic glutamine of the GNBP and, in most cases, the insertion of a catalytic arginine of GAP into the active site. Rap1 is a close homologue of Ras but does not possess the catalytic glutamine essential for GTP hydrolysis in all other Ras-like and Galpha proteins. Furthermore, RapGAPs are not related to other GAPs and apparently do not use a catalytic arginine residue. Here we present the crystal structure of the catalytic domain of the Rap1-specific Rap1GAP at 2.9 A. By mutational analysis, fluorescence titration and stopped-flow kinetic assay, we demonstrate that Rap1GAP provides a catalytic asparagine to stimulate GTP hydrolysis. Implications for the disease tuberous sclerosis are discussed.
About this Structure
1SRQ is a Single protein structure of sequence from Homo sapiens with and as ligands. Full crystallographic information is available from OCA.
Reference
The GTPase-activating protein Rap1GAP uses a catalytic asparagine., Daumke O, Weyand M, Chakrabarti PP, Vetter IR, Wittinghofer A, Nature. 2004 May 13;429(6988):197-201. PMID:15141215
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