1AZT

GS-ALPHA COMPLEXED WITH GTP-GAMMA-S

Summary for 1AZT

• Entry DOI: 10.2210/pdb1azt/pdb
• Descriptor: GS-ALPHA, MAGNESIUM ION, PHOSPHATE ION, ... (5 entities in total)
• Functional Keywords: hydrolase, signal transducing protein, gtp-binding protein
• Biological source: Bos taurus (cattle)
• Cellular location: Cell membrane; Lipid-anchor (By similarity): P04896
• Total number of polymer chains: 2
• Total formula weight: 96071.64

Authors

Tesmer, J.J.G.,Sprang, S.R. (deposition date: 1997-11-20, release date: 1998-02-25, Last modification date: 2024-05-22)

Primary citation

Sunahara, R.K.,Tesmer, J.J.,Gilman, A.G.,Sprang, S.R.
Crystal structure of the adenylyl cyclase activator Gsalpha
Science, 278:1943-1947, 1997

PubMed Abstract: The crystal structure of Gsalpha, the heterotrimeric G protein alpha subunit that stimulates adenylyl cyclase, was determined at 2.5 A in a complex with guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS). Gsalpha is the prototypic member of a family of GTP-binding proteins that regulate the activities of effectors in a hormone-dependent manner. Comparison of the structure of Gsalpha.GTPgammaS with that of Gialpha.GTPgammaS suggests that their effector specificity is primarily dictated by the shape of the binding surface formed by the switch II helix and the alpha3-beta5 loop, despite the high sequence homology of these elements. In contrast, sequence divergence explains the inability of regulators of G protein signaling to stimulate the GTPase activity of Gsalpha. The betagamma binding surface of Gsalpha is largely conserved in sequence and structure to that of Gialpha, whereas differences in the surface formed by the carboxyl-terminal helix and the alpha4-beta6 loop may mediate receptor specificity.

PubMed: 9395396
DOI: 10.1126/science.278.5345.1943

Experimental method

X-RAY DIFFRACTION (2.3 Å)