Structural highlights
Function
[RB27B_MOUSE] May be involved in targeting uroplakins to urothelial apical membranes (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Members of the Rab family of small GTPases regulate membrane traffic within the cell by recruiting their specific effectors in a nucleotide-dependent manner. The Rab27 subfamily consists of Rab27a and Rab27b, which share 70% sequence identity. By interacting with a large set of effector proteins such as melanophilin and granuphilin, both Rab27a and Rab27b regulate the exocytosis of secretory lysosomes. Here, the crystal structures of mouse Rab27b in complex with GDP have been determined in three distinct crystal lattices. Surprisingly, Rab27b-GDP exists in an open conformation with protruding switch and interswitch regions, which are stabilized through dimerization by means of domain-swapping in the crystals. In contrast, small-angle X-ray scattering measurements showed an extended monomer form of Rab27b in solution. The observed dimer formation of Rab27b-GDP in the crystals would restrain the highly flexible switch regions. Possible biological implications of this atypical structure of Rab27b and its plausible influence in effector interaction are discussed.
Structure of the small GTPase Rab27b shows an unexpected swapped dimer.,Chavas LM, Torii S, Kamikubo H, Kawasaki M, Ihara K, Kato R, Kataoka M, Izumi T, Wakatsuki S Acta Crystallogr D Biol Crystallogr. 2007 Jul;63(Pt 7):769-79. Epub 2007 Jun 15. PMID:17582168[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Chavas LM, Torii S, Kamikubo H, Kawasaki M, Ihara K, Kato R, Kataoka M, Izumi T, Wakatsuki S. Structure of the small GTPase Rab27b shows an unexpected swapped dimer. Acta Crystallogr D Biol Crystallogr. 2007 Jul;63(Pt 7):769-79. Epub 2007 Jun 15. PMID:17582168 doi:10.1107/S0907444907019725
