Download MendeleyCrystal structure of Rab9 complexed to GDP reveals a dimer with an active conformation of switch II.
Wittmann, J.G., Rudolph, M.G.(2004) FEBS Lett 568: 23-29
- PubMed: 15196914
- DOI: https://doi.org/10.1016/j.febslet.2004.05.004
- Primary Citation of Related Structures:
1S8F - PubMed Abstract:
The small GTPase Rab9 is an essential regulator of vesicular transport from the late endosome to the trans-Golgi network, as monitored by the redirection of the mannose-6-phosphate receptors. The crystal structure of Rab9 complexed to GDP, Mg(2+), and Sr(2+) reveals a unique dimer formed by an intermolecular beta-sheet that buries the switch I regions. Surface area and shape complementarity calculations suggest that Rab9 dimers can form an inactive, membrane-bound pool of Rab9 . GDP that is independent of GDI. Mg(2+)-bound Rab9 represents an inactive state, but Sr(2+)-bound Rab9 . GDP displays activated switch region conformations, mimicking those of the GTP state. A hydrophobic tetrad is formed resembling an effector-discriminating epitope found only in GTP-bound Rab proteins.
Organizational Affiliation:
Department of Molecular Structural Biology and GZMB, Justus-von-Liebig-Weg 11, Georg-August University, 37077 Göttingen, Germany.
