1DPF

CRYSTAL STRUCTURE OF A MG-FREE FORM OF RHOA COMPLEXED WITH GDP

Summary for 1DPF

• Entry DOI: 10.2210/pdb1dpf/pdb
• Related: 1a2b
• Descriptor: RHOA, GUANOSINE-5'-DIPHOSPHATE (3 entities in total)
• Functional Keywords: protein rhoa-gdp complex, gene regulation-signaling protein complex, gene regulation/signaling protein
• Biological source: Homo sapiens (human)
• Cellular location: Cell membrane; Lipid-anchor; Cytoplasmic side: P61586
• Total number of polymer chains: 1
• Total formula weight: 20637.39

Authors

Shimizu, T.,Ihara, K.,Maesaki, R.,Kuroda, S.,Kaibuchi, K.,Hakoshima, T. (deposition date: 1999-12-27, release date: 2000-06-21, Last modification date: 2024-02-07)

Primary citation

Shimizu, T.,Ihara, K.,Maesaki, R.,Kuroda, S.,Kaibuchi, K.,Hakoshima, T.
An open conformation of switch I revealed by the crystal structure of a Mg2+-free form of RHOA complexed with GDP. Implications for the GDP/GTP exchange mechanism.
J.Biol.Chem., 275:18311-18317, 2000

PubMed Abstract: Mg(2+) ions are essential for guanosine triphosphatase (GTPase) activity and play key roles in guanine nucleotide binding and preserving the structural integrity of GTP-binding proteins. We determined the crystal structure of a small GTPase RHOA complexed with GDP in the absence of Mg(2+) at 2.0-A resolution. Elimination of a Mg(2+) ion induces significant conformational changes in the switch I region that opens up the nucleotide-binding site. Similar structural changes have been observed in the switch regions of Ha-Ras bound to its guanine nucleotide exchange factor, Sos. This RHOA-GDP structure reveals an important regulatory role for Mg(2+) and suggests that guanine nucleotide exchange factor may utilize this feature of switch I to produce an open conformation in GDP/GTP exchange.

PubMed: 10748207
DOI: 10.1074/jbc.M910274199

Experimental method

X-RAY DIFFRACTION (2 Å)