2X3X: Structure Of Mouse Syndapin I (Crystal Form 1)

Members of the Bin/amphiphysin/Rvs (BAR) domain protein superfamily are involved in membrane remodeling in various cellular pathways ranging from endocytic vesicle and T-tubule formation to cell migration and neuromorphogenesis. Membrane curvature induction and stabilization are encoded within the BAR or Fer-CIP4 homology-BAR (F-BAR) domains, alpha-helical coiled coils that dimerize into membrane-binding modules. BAR/F-BAR domain proteins often contain an SH3 domain, which recruits binding partners such as the oligomeric membrane-fissioning GTPase dynamin. How precisely BAR/F-BAR domain-mediated membrane deformation is regulated at the cellular level is unknown. Here we present the crystal structures of full-length syndapin 1 and its F-BAR domain. Our data show that syndapin 1 F-BAR-mediated membrane deformation is subject to autoinhibition by its SH3 domain. Release from the clamped conformation is driven by association of syndapin 1 SH3 with the proline-rich domain of dynamin 1, thereby unlocking its potent membrane-bending activity. We hypothesize that this mechanism might be commonly used to regulate BAR/F-BAR domain-induced membrane deformation and to potentially couple this process to dynamin-mediated fission. Our data thus suggest a structure-based model for SH3-mediated regulation of BAR/F-BAR domain function.
PDB ID: 2X3XDownload
MMDB ID: 81188
PDB Deposition Date: 2010/1/28
Updated in MMDB: 2012/09
Experimental Method:
x-ray diffraction
Resolution: 3.35  Å
Source Organism:
Similar Structures:
Biological Unit for 2X3X: dimeric; determined by author and by software (PISA)
Molecular Components in 2X3X
Label Count Molecule
Proteins (2 molecules)
Protein Kinase C and Casein Kinase Substrate in Neurons Protein 1(Gene symbol: Pacsin1)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB