Structural highlights
3ah8 is a 4 chain structure with sequence from Bovin, Chromobacterium sp. and Lk3 transgenic mice. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | |
| NonStd Res: | , , , , , , |
| Gene: | gmhB (LK3 transgenic mice), GNB1 (BOVIN), GNG2 (BOVIN) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[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.[1] [GBG2_BOVIN] Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems. The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction. [GBB1_BOVIN] Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems. The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Heterotrimeric GTP-binding proteins (G proteins) transmit extracellular stimuli perceived by G protein-coupled receptors (GPCRs) to intracellular signaling cascades. Hundreds of GPCRs exist in humans and are the targets of a large percentage of the pharmaceutical drugs used today. Because G proteins are regulated by GPCRs, small molecules that directly modulate G proteins have the potential to become therapeutic agents. However, strategies to develop modulators have been hampered by a lack of structural knowledge of targeting sites for specific modulator binding. Here we present the mechanism of action of the cyclic depsipeptide YM-254890, which is a recently discovered G(q)-selective inhibitor. YM-254890 specifically inhibits the GDP/GTP exchange reaction of alpha subunit of G(q) protein (Galpha(q)) by inhibiting the GDP release from Galpha(q). X-ray crystal structure analysis of the Galpha(q)betagamma-YM-254890 complex shows that YM-254890 binds the hydrophobic cleft between two interdomain linkers connecting the GTPase and helical domains of the Galpha(q). The binding stabilizes an inactive GDP-bound form through direct interactions with switch I and impairs the linker flexibility. Our studies provide a novel targeting site for the development of small molecules that selectively inhibit each Galpha subunit and an insight into the molecular mechanism of G protein activation.
Structural basis for the specific inhibition of heterotrimeric Gq protein by a small molecule.,Nishimura A, Kitano K, Takasaki J, Taniguchi M, Mizuno N, Tago K, Hakoshima T, Itoh H Proc Natl Acad Sci U S A. 2010 Jul 16. PMID:20639466[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Shu FJ, Ramineni S, Amyot W, Hepler JR. Selective interactions between Gi alpha1 and Gi alpha3 and the GoLoco/GPR domain of RGS14 influence its dynamic subcellular localization. Cell Signal. 2007 Jan;19(1):163-76. Epub 2006 Jul 25. PMID:16870394 doi:http://dx.doi.org/10.1016/j.cellsig.2006.06.002
- ↑ Nishimura A, Kitano K, Takasaki J, Taniguchi M, Mizuno N, Tago K, Hakoshima T, Itoh H. Structural basis for the specific inhibition of heterotrimeric Gq protein by a small molecule. Proc Natl Acad Sci U S A. 2010 Jul 16. PMID:20639466
