Structure and plasticity of endophilin and sorting nexin 9.
Wang, Q., Kaan, H.Y., Hooda, R.N., Goh, S.L., Sondermann, H.(2008) Structure 16: 1574-1587
- PubMed: 18940612 
- DOI: https://doi.org/10.1016/j.str.2008.07.016
- Primary Citation of Related Structures:  
3DYT, 3DYU - PubMed Abstract: 
Endophilin and Sorting Nexin 9 (Snx9) play key roles in endocytosis by membrane curvature sensing and remodeling via their Bin/Amphiphysin/Rvs (BAR) domains. BAR and the related F-BAR domains form dimeric, crescent-shaped units that occur N- or C-terminally to other lipid-binding, adaptor, or catalytic modules. In crystal structures, the PX-BAR unit of Snx9 (Snx9(PX-BAR)) adopts an overall compact, moderately curved conformation. SAXS-based solution studies revealed an alternative, more curved state of Snx9(PX-BAR) in which the PX domains are flexibly connected to the BAR domains, providing a model for how Snx9 exhibits lipid-dependent curvature preferences. In contrast, Endophilin appears to be rigid in solution, and the SH3 domains are located at the distal tips of a BAR domain dimer with fixed curvature. We also observed tip-to-tip interactions between the BAR domains in a trigonal crystal form of Snx9(PX-BAR) reminiscent of functionally important interactions described for F-BAR domains.
Organizational Affiliation: 
Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.