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| | ==A Galpha P-loop mutation prevents transition to the activated state: G42R bound to RGS14 GoLoco== | | ==A Galpha P-loop mutation prevents transition to the activated state: G42R bound to RGS14 GoLoco== |
| - | <StructureSection load='3qi2' size='340' side='right' caption='[[3qi2]], [[Resolution|resolution]] 2.80Å' scene=''> | + | <StructureSection load='3qi2' size='340' side='right'caption='[[3qi2]], [[Resolution|resolution]] 2.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3qi2]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3QI2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3QI2 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3qi2]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3QI2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3QI2 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3qe0|3qe0]], [[2om2|2om2]], [[1kjy|1kjy]], [[1y3a|1y3a]]</td></tr> | + | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[3qe0|3qe0]], [[2om2|2om2]], [[1kjy|1kjy]], [[1y3a|1y3a]]</div></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">GNAI1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr> | + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">GNAI1 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Heterotrimeric_G-protein_GTPase Heterotrimeric G-protein GTPase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.5.1 3.6.5.1] </span></td></tr> | + | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Heterotrimeric_G-protein_GTPase Heterotrimeric G-protein GTPase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.5.1 3.6.5.1] </span></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=3qi2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3qi2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3qi2 RCSB], [http://www.ebi.ac.uk/pdbsum/3qi2 PDBsum]</span></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=3qi2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3qi2 OCA], [https://pdbe.org/3qi2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3qi2 RCSB], [https://www.ebi.ac.uk/pdbsum/3qi2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3qi2 ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/GNAI1_HUMAN GNAI1_HUMAN]] 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:17635935</ref> <ref>PMID:17264214</ref> [[http://www.uniprot.org/uniprot/RGS14_HUMAN RGS14_HUMAN]] Acts as a regulator of G protein signaling (RGS). Modulates G protein alpha subunits nucleotide exchange and hydrolysis activities by functioning either as a GTPase-activating protein (GAP), thereby driving G protein alpha subunits into their inactive GDP-bound form, or as a GDP-dissociation inhibitor (GDI). Confers GDI activity on G(i) alpha subunits GNAI1 and GNAI3, but not G(o) alpha subunit GNAO1 and G(i) alpha subunit GNAI2. Confers GAP activity on G(o) alpha subunit GNAI0 and G(i) alpha subunits GNAI2 and GNAI3. May act as a scaffold integrating G protein and Ras/Raf MAPkinase signaling pathways. Inhibits platelet-derived growth factor (PDGF)-stimulated ERK1/ERK2 phosphorylation; a process depending on its interaction with HRAS1 and that is reversed by G(i) alpha subunit GNAI1. Acts as a positive modulator of microtubule polymerisation and spindle organization through a G(i)-alpha-dependent mechanism. Plays a role in cell division. Probably required for the nerve growth factor (NGF)-mediated neurite outgrowth. May be involved in visual memory processing capacity and hippocampal-based learning and memory.<ref>PMID:15917656</ref> <ref>PMID:17635935</ref> | + | [[https://www.uniprot.org/uniprot/GNAI1_HUMAN GNAI1_HUMAN]] 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:17635935</ref> <ref>PMID:17264214</ref> [[https://www.uniprot.org/uniprot/RGS14_HUMAN RGS14_HUMAN]] Acts as a regulator of G protein signaling (RGS). Modulates G protein alpha subunits nucleotide exchange and hydrolysis activities by functioning either as a GTPase-activating protein (GAP), thereby driving G protein alpha subunits into their inactive GDP-bound form, or as a GDP-dissociation inhibitor (GDI). Confers GDI activity on G(i) alpha subunits GNAI1 and GNAI3, but not G(o) alpha subunit GNAO1 and G(i) alpha subunit GNAI2. Confers GAP activity on G(o) alpha subunit GNAI0 and G(i) alpha subunits GNAI2 and GNAI3. May act as a scaffold integrating G protein and Ras/Raf MAPkinase signaling pathways. Inhibits platelet-derived growth factor (PDGF)-stimulated ERK1/ERK2 phosphorylation; a process depending on its interaction with HRAS1 and that is reversed by G(i) alpha subunit GNAI1. Acts as a positive modulator of microtubule polymerisation and spindle organization through a G(i)-alpha-dependent mechanism. Plays a role in cell division. Probably required for the nerve growth factor (NGF)-mediated neurite outgrowth. May be involved in visual memory processing capacity and hippocampal-based learning and memory.<ref>PMID:15917656</ref> <ref>PMID:17635935</ref> |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| | </div> | | </div> |
| - | | + | <div class="pdbe-citations 3qi2" style="background-color:#fffaf0;"></div> |
| - | ==See Also== | + | |
| - | *[[Guanine nucleotide-binding protein|Guanine nucleotide-binding protein]]
| + | |
| | == References == | | == References == |
| | <references/> | | <references/> |
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| | </StructureSection> | | </StructureSection> |
| | [[Category: Heterotrimeric G-protein GTPase]] | | [[Category: Heterotrimeric G-protein GTPase]] |
| - | [[Category: Homo sapiens]] | + | [[Category: Human]] |
| | + | [[Category: Large Structures]] |
| | [[Category: Bosch, D E]] | | [[Category: Bosch, D E]] |
| | [[Category: Kimple, A J]] | | [[Category: Kimple, A J]] |
| Structural highlights
Function
[GNAI1_HUMAN] 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.[1] [2] [RGS14_HUMAN] Acts as a regulator of G protein signaling (RGS). Modulates G protein alpha subunits nucleotide exchange and hydrolysis activities by functioning either as a GTPase-activating protein (GAP), thereby driving G protein alpha subunits into their inactive GDP-bound form, or as a GDP-dissociation inhibitor (GDI). Confers GDI activity on G(i) alpha subunits GNAI1 and GNAI3, but not G(o) alpha subunit GNAO1 and G(i) alpha subunit GNAI2. Confers GAP activity on G(o) alpha subunit GNAI0 and G(i) alpha subunits GNAI2 and GNAI3. May act as a scaffold integrating G protein and Ras/Raf MAPkinase signaling pathways. Inhibits platelet-derived growth factor (PDGF)-stimulated ERK1/ERK2 phosphorylation; a process depending on its interaction with HRAS1 and that is reversed by G(i) alpha subunit GNAI1. Acts as a positive modulator of microtubule polymerisation and spindle organization through a G(i)-alpha-dependent mechanism. Plays a role in cell division. Probably required for the nerve growth factor (NGF)-mediated neurite outgrowth. May be involved in visual memory processing capacity and hippocampal-based learning and memory.[3] [4]
Publication Abstract from PubMed
Heterotrimeric G-proteins are molecular switches integral to a panoply of different physiological responses that many organisms make to environmental cues. The switch from inactive to active Galphabetagamma heterotrimer relies on nucleotide cycling by the Galpha subunit: exchange of GTP for GDP activates Galpha, whereas its intrinsic enzymatic activity catalyzes GTP hydrolysis to GDP and inorganic phosphate, thereby reverting Galpha to its inactive state. In several genetic studies of filamentous fungi, such as the rice blast fungus Magnaporthe oryzae, a G42R mutation in the phosphate-binding loop of Galpha subunits is assumed to be GTPase-deficient and thus constitutively active. Here, we demonstrate that Galpha(G42R) mutants are not GTPase deficient, but rather incapable of achieving the activated conformation. Two crystal structure models suggest that Arg-42 prevents a typical switch region conformational change upon Galpha(i1)(G42R) binding to GDP.AlF(4) (-) or GTP, but rotameric flexibility at this locus allows for unperturbed GTP hydrolysis. Galpha(G42R) mutants do not engage the active state-selective peptide KB-1753 nor RGS domains with high affinity, but instead favor interaction with Gbetagamma and GoLoco motifs in any nucleotide state. The corresponding Galpha(q)(G48R) mutant is not constitutively active in cells and responds poorly to aluminum tetrafluoride activation. Comparative analyses of M. oryzae strains harboring either G42R or GTPase-deficient Q/L mutations in the Galpha subunits MagA or MagB illustrate functional differences in environmental cue processing and intracellular signaling outcomes between these two Galpha mutants, thus demonstrating the in vivo functional divergence of G42R and activating G-protein mutants.
A P-loop Mutation in Galpha Subunits Prevents Transition to the Active State: Implications for G-protein Signaling in Fungal Pathogenesis.,Bosch DE, Willard FS, Ramanujam R, Kimple AJ, Willard MD, Naqvi NI, Siderovski DP PLoS Pathog. 2012 Feb;8(2):e1002553. Epub 2012 Feb 23. PMID:22383884[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Cho H, Kehrl JH. Localization of Gi alpha proteins in the centrosomes and at the midbody: implication for their role in cell division. J Cell Biol. 2007 Jul 16;178(2):245-55. PMID:17635935 doi:10.1083/jcb.200604114
- ↑ Johnston CA, Siderovski DP. Structural basis for nucleotide exchange on G alpha i subunits and receptor coupling specificity. Proc Natl Acad Sci U S A. 2007 Feb 6;104(6):2001-6. Epub 2007 Jan 30. PMID:17264214
- ↑ Martin-McCaffrey L, Willard FS, Pajak A, Dagnino L, Siderovski DP, D'Souza SJ. RGS14 is a microtubule-associated protein. Cell Cycle. 2005 Jul;4(7):953-60. Epub 2005 Jul 28. PMID:15917656
- ↑ Cho H, Kehrl JH. Localization of Gi alpha proteins in the centrosomes and at the midbody: implication for their role in cell division. J Cell Biol. 2007 Jul 16;178(2):245-55. PMID:17635935 doi:10.1083/jcb.200604114
- ↑ Bosch DE, Willard FS, Ramanujam R, Kimple AJ, Willard MD, Naqvi NI, Siderovski DP. A P-loop Mutation in Galpha Subunits Prevents Transition to the Active State: Implications for G-protein Signaling in Fungal Pathogenesis. PLoS Pathog. 2012 Feb;8(2):e1002553. Epub 2012 Feb 23. PMID:22383884 doi:10.1371/journal.ppat.1002553
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