3BC1: Crystal Structure Of The Complex Rab27a-slp2a

Rab GTPases coordinate vesicular trafficking within eukaryotic cells by collaborating with a set of effector proteins. Rab27a regulates numerous exocytotic pathways, and its dysfunction causes the Griscelli syndrome human immunodeficiency. Exophilin4/Slp2-a localizes on phosphatidylserine-enriched plasma membrane, and its N-terminal Rab27-binding domain (RBD27) specifically recognizes Rab27 on the surfaces of melanosomes and secretory granules prior to docking and fusion. To characterize the selective binding of Rab27 to 11 various effectors, we have determined the 1.8 A resolution structure of Rab27a in complex with Exophilin4 RBD27. The effector packs against the switch and interswitch elements of Rab27a, and specific affinity toward Rab27a is modulated by a shift in the orientation of the effector structural motif (S/T)(G/L)xW(F/Y)(2). The observed structural complementation between the interacting surfaces of Rab27a and Exophilin4 sheds light on the disparities among the Rab27 effectors and outlines a general mechanism for their recruitment.
PDB ID: 3BC1Download
MMDB ID: 66439
PDB Deposition Date: 2007/11/12
Updated in MMDB: 2008/12
Experimental Method:
x-ray diffraction
Resolution: 1.8  Å
Source Organism:
Mus musculus
Similar Structures:
Biological Unit for 3BC1: dimeric; determined by author and by software (PISA)
Molecular Components in 3BC1
Label Count Molecule
Proteins (2 molecules)
Ras-related Protein Rab-27a(Gene symbol: Rab27a)
Molecule annotation
Synaptotagmin-like Protein 2(Gene symbol: SYTL2)
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB