2RAP

THE SMALL G PROTEIN RAP2A IN COMPLEX WITH GTP

Summary for 2RAP

• Entry DOI: 10.2210/pdb2rap/pdb
• Descriptor: RAP2A, MAGNESIUM ION, GUANOSINE-5'-TRIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: g protein, gtp hydrolysis, ras, rap2a
• Biological source: Homo sapiens (human)
• Cellular location: Recycling endosome membrane; Lipid-anchor; Cytoplasmic side: P10114
• Total number of polymer chains: 1
• Total formula weight: 19493.05

Authors

Cherfils, J.,Menetrey, J.,Lebras, G. (deposition date: 1998-05-06, release date: 1998-06-17, Last modification date: 2024-02-21)

Primary citation

Cherfils, J.,Menetrey, J.,Le Bras, G.,Janoueix-Lerosey, I.,de Gunzburg, J.,Garel, J.R.,Auzat, I.
Crystal structures of the small G protein Rap2A in complex with its substrate GTP, with GDP and with GTPgammaS.
EMBO J., 16:5582-5591, 1997

PubMed Abstract: The small G protein Rap2A has been crystallized in complex with GDP, GTP and GTPgammaS. The Rap2A-GTP complex is the first structure of a small G protein with its natural ligand GTP. It shows that the hydroxyl group of Tyr32 forms a hydrogen bond with the gamma-phosphate of GTP and with Gly13. This interaction does not exist in the Rap2A-GTPgammaS complex. Tyr32 is conserved in many small G proteins, which probably also form this hydrogen bond with GTP. In addition, Tyr32 is structurally equivalent to a conserved arginine that binds GTP in trimeric G proteins. The actual participation of Tyr32 in GTP hydrolysis is not yet clear, but several possible roles are discussed. The conformational changes between the GDP and GTP complexes are located essentially in the switch I and II regions as described for the related oncoprotein H-Ras. However, the mobile segments vary in length and in the amplitude of movement. This suggests that even though similar regions might be involved in the GDP-GTP cycle of small G proteins, the details of the changes will be different for each G protein and will ensure the specificity of its interaction with a given set of cellular proteins.

PubMed: 9312017
DOI: 10.1093/emboj/16.18.5582

Experimental method

X-RAY DIFFRACTION (2.6 Å)