Structure of the GDP-bound G domain of the RGK protein Rem2.
RGK proteins are atypical small GTP-binding proteins that are involved in the regulation of voltage-dependent calcium channels and actin cytoskeleton remodelling. The structure of the Rem2 G domain bound to GDP is reported here in a monoclinic crystal form at 2.66 Å resolution. It is very similar to the structure determined previously from an orthorhombic crystal form. However, differences in the crystal-packing environment revealed that the switch I and switch II regions are flexible and not ordered as previously reported. Comparison of the available RGK protein structures along with those of other small GTP-binding proteins highlights two structural features characteristic of this atypical family and suggests that the conserved tryptophan residue in the DXWEX motif may be a structural determinant of the nucleotide-binding affinity.
Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, 91198 Gif-sur-Yvette, France.
Philippe
P
Reymond
Aline
A
Coquard
Mélanie
M
Chenon
Mahel
M
Zeghouf
Ahmed
A
El Marjou
Andrew
A
Thompson
Julie
J
Ménétrey
D000595:Amino Acid Sequence; D000818:Animals; D006153:Guanosine Diphosphate; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020559:Monomeric GTP-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D054730:Protein Interaction Domains and Motifs; D017434:Protein Structure, Tertiary; D051381:Rats; D016415:Sequence Alignment
D006153:Guanosine Diphosphate; D020559:Monomeric GTP-Binding Proteins; C484604:Rem2 protein, rat