The PX-BAR membrane-remodeling unit of sorting nexin 9

EMBO J. 2007 Nov 14;26(22):4788-800. doi: 10.1038/sj.emboj.7601889. Epub 2007 Oct 18.


Sorting nexins (SNXs) form a family of proteins known to interact with components in the endosomal system and to regulate various steps of vesicle transport. Sorting nexin 9 (SNX9) is involved in the late stages of clathrin-mediated endocytosis in non-neuronal cells, where together with the GTPase dynamin, it participates in the formation and scission of the vesicle neck. We report here crystal structures of the functional membrane-remodeling unit of SNX9 and show that it efficiently tubulates lipid membranes in vivo and in vitro. Elucidation of the protein superdomain structure, together with mutational analysis and biochemical and cell biological experiments, demonstrated how the SNX9 PX and BAR domains work in concert in targeting and tubulation of phosphoinositide-containing membranes. The study provides insights into the SNX9-induced membrane modulation mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Membrane / metabolism
  • Crystallization
  • HeLa Cells
  • Humans
  • Liposomes / metabolism
  • Mutation
  • Protein Interaction Domains and Motifs*
  • Sorting Nexins
  • Vesicular Transport Proteins / chemistry*
  • Vesicular Transport Proteins / genetics
  • Vesicular Transport Proteins / metabolism*


  • Liposomes
  • SNX9 protein, human
  • Sorting Nexins
  • Vesicular Transport Proteins