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6ukt
From Proteopedia
(Difference between revisions)
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| - | '''Unreleased structure''' | ||
| - | + | ==Cryo-EM structure of mammalian Ric-8A:Galpha(i):nanobody complex== | |
| + | <StructureSection load='6ukt' size='340' side='right'caption='[[6ukt]], [[Resolution|resolution]] 3.87Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[6ukt]] is a 6 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6UKT OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6UKT FirstGlance]. <br> | ||
| + | </td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=SEP:PHOSPHOSERINE'>SEP</scene>, <scene name='pdbligand=TPO:PHOSPHOTHREONINE'>TPO</scene></td></tr> | ||
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ukt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ukt OCA], [http://pdbe.org/6ukt PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ukt RCSB], [http://www.ebi.ac.uk/pdbsum/6ukt PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ukt ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [[http://www.uniprot.org/uniprot/GNAI1_RAT GNAI1_RAT]] Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems. The G(i) proteins are involved in hormonal regulation of adenylate cyclase: they inhibit the cyclase in response to beta-adrenergic stimuli. The inactive GDP-bound form prevents the association of RGS14 with centrosomes and is required for the translocation of RGS14 from the cytoplasm to the plasma membrane. May play a role in cell division.<ref>PMID:16870394</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Ric-8A is a cytosolic Guanine Nucleotide exchange Factor (GEF) that activates heterotrimeric G protein alpha subunits (Galpha) and serves as an essential Galpha chaperone. Mechanisms by which Ric-8A catalyzes these activities, which are stimulated by Casein Kinase II phosphorylation, are unknown. We report the structure of the nanobody-stabilized complex of nucleotide-free Galpha bound to phosphorylated Ric-8A at near atomic resolution by cryo-electron microscopy and X-ray crystallography. The mechanism of Ric-8A GEF activity differs considerably from that employed by G protein-coupled receptors at the plasma membrane. Ric-8A engages a specific conformation of Galpha at multiple interfaces to form a complex that is stabilized by phosphorylation within a Ric-8A segment that connects two Galpha binding sites. The C-terminus of Galpha is ejected from its beta sheet core, thereby dismantling the GDP binding site. Ric-8A binds to the exposed Galpha beta sheet and switch II to stabilize the nucleotide-free state of Galpha. | ||
| - | + | Structure of the G protein chaperone and guanine nucleotide exchange factor Ric-8A bound to Galphai1.,McClelland LJ, Zhang K, Mou TC, Johnston J, Yates-Hansen C, Li S, Thomas CJ, Doukov TI, Triest S, Wohlkonig A, Tall GG, Steyaert J, Chiu W, Sprang SR Nat Commun. 2020 Feb 26;11(1):1077. doi: 10.1038/s41467-020-14943-4. PMID:32103024<ref>PMID:32103024</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| + | <div class="pdbe-citations 6ukt" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Chiu, W]] | ||
| + | [[Category: Johnston, J D]] | ||
| + | [[Category: Mou, T C]] | ||
| + | [[Category: Sprang, S R]] | ||
| + | [[Category: Zhang, K]] | ||
| + | [[Category: G protein]] | ||
| + | [[Category: Gef]] | ||
| + | [[Category: Ric-8a]] | ||
| + | [[Category: Signaling protein]] | ||
Current revision
Cryo-EM structure of mammalian Ric-8A:Galpha(i):nanobody complex
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Categories: Large Structures | Chiu, W | Johnston, J D | Mou, T C | Sprang, S R | Zhang, K | G protein | Gef | Ric-8a | Signaling protein
