1svs

<table><tr><td colspan='2'>[[1svs]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Buffalo_rat Buffalo rat]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SVS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1SVS FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GNP:PHOSPHOAMINOPHOSPHONIC+ACID-GUANYLATE+ESTER'>GNP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1svk|1svk]]</div></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">GNAI1, GNAI-1 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=10116 Buffalo rat])</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>

[[https://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>

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== Publication Abstract from PubMed ==

Heterotrimeric G protein alpha (G alpha) subunits possess intrinsic GTPase activity that leads to functional deactivation with a rate constant of approximately 2 min(-1) at 30 degrees C. GTP hydrolysis causes conformational changes in three regions of G alpha, including Switch I and Switch II. Mutation of G202--&gt;A in Switch II of G alpha(i1) accelerates the rates of both GTP hydrolysis and conformational change, which is measured by the loss of fluorescence from Trp-211 in Switch II. Mutation of K180--&gt;P in Switch I increases the rate of conformational change but decreases the GTPase rate, which causes transient but substantial accumulation of a low-fluorescence G alpha(i1).GTP species. Isothermal titration calorimetric analysis of the binding of (G202A)G alpha(i1) and (K180P)G alpha(i1) to the GTPase-activating protein RGS4 indicates that the G202A mutation stabilizes the pretransition state-like conformation of G alpha(i1) that is mimicked by the complex of G alpha(i1) with GDP and magnesium fluoroaluminate, whereas the K180P mutation destabilizes this state. The crystal structures of (K180P)G alpha(i1) bound to a slowly hydrolyzable GTP analog, and the GDP.magnesium fluoroaluminate complex provide evidence that the Mg(2+) binding site is destabilized and that Switch I is torsionally restrained by the K180P mutation. The data are consistent with a catalytic mechanism for G alpha in which major conformational transitions in Switch I and Switch II are obligate events that precede the bond-breaking step in GTP hydrolysis. In (K180P)G alpha(i1), the two events are decoupled kinetically, whereas in the native protein they are concerted.

Uncoupling conformational change from GTP hydrolysis in a heterotrimeric G protein alpha-subunit.,Thomas CJ, Du X, Li P, Wang Y, Ross EM, Sprang SR Proc Natl Acad Sci U S A. 2004 May 18;101(20):7560-5. Epub 2004 May 5. PMID:15128951<ref>PMID:15128951</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 1svs" style="background-color:#fffaf0;"></div>

[[Category: Buffalo rat]]

[[Category: Heterotrimeric G-protein GTPase]]

[[Category: Du, X]]

[[Category: Li, P]]

[[Category: Ross, E M]]

[[Category: Sprang, S R]]

[[Category: Thomas, C J]]

[[Category: Wang, Y]]

[[Category: Signaling protein]]