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Structure of the GDP-bound G domain of the RGK protein Rem2.

ABSTRACT: 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.

SUBMITTER: Reymond P

PROVIDER: S-EPMC3370897 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Structure of the GDP-bound G domain of the RGK protein Rem2.

Reymond Philippe P Coquard Aline A Chenon Mélanie M Zeghouf Mahel M El Marjou Ahmed A Thompson Andrew A Ménétrey Julie J

Acta crystallographica. Section F, Structural biology and crystallization communications 20120522 Pt 6

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 or ...[more]

PMID: 22684057

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