Structural basis for recruitment of GRIP domain golgin-245 by small GTPase Arl1.Wu, M., Lu, L., Hong, W., Song, H.
(2004) Nat Struct Mol Biol 11: 86-94
- PubMed: 14718928
- DOI: https://doi.org/10.1038/nsmb714
- Primary Citation of Related Structures:
- PubMed Abstract:
Recruitment of the GRIP domain golgins to the trans-Golgi network is mediated by Arl1, a member of the ARF/Arl small GTPase family, through interaction between their GRIP domains and Arl1-GTP. The crystal structure of Arl1-GTP in complex with the GRIP domain of golgin-245 shows that Arl1-GTP interacts with the GRIP domain predominantly in a hydrophobic manner, with the switch II region conferring the main recognition surface. The involvement of the switch and interswitch regions in the interaction between Arl1-GTP and GRIP accounts for the specificity of GRIP domain for Arl1-GTP. Mutations that abolished the Arl1-mediated Golgi localization of GRIP domain golgins have been mapped on the interface between Arl1-GTP and GRIP. Notably, the GRIP domain forms a homodimer in which each subunit interacts separately with one Arl1-GTP. Mutations disrupting the GRIP domain dimerization also abrogated its Golgi targeting, suggesting that the dimeric form of GRIP domain is a functional unit.
Laboratory of Macromolecular Structure, Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609.