Reconstitution of the tubular endoplasmic reticulum network with purified components

Nature. 2017 Mar 9;543(7644):257-260. doi: 10.1038/nature21387. Epub 2017 Feb 22.


Organelles display characteristic morphologies that are intimately tied to their cellular function, but how organelles are shaped is poorly understood. The endoplasmic reticulum is particularly intriguing, as it comprises morphologically distinct domains, including a dynamic network of interconnected membrane tubules. Several membrane proteins have been implicated in network formation, but how exactly they mediate network formation and whether they are all required are unclear. Here we reconstitute a dynamic tubular membrane network with purified endoplasmic reticulum proteins. Proteoliposomes containing the membrane-fusing GTPase Sey1p (refs 6, 7) and the curvature-stabilizing protein Yop1p (refs 8, 9) from Saccharomyces cerevisiae form a tubular network upon addition of GTP. The tubules rapidly fragment when GTP hydrolysis of Sey1p is inhibited, indicating that network maintenance requires continuous membrane fusion and that Yop1p favours the generation of highly curved membrane structures. Sey1p also forms networks with other curvature-stabilizing proteins, including reticulon and receptor expression-enhancing proteins (REEPs) from different species. Atlastin, the vertebrate orthologue of Sey1p, forms a GTP-hydrolysis-dependent network on its own, serving as both a fusion and curvature-stabilizing protein. Our results show that organelle shape can be generated by a surprisingly small set of proteins and represents an energy-dependent steady state between formation and disassembly.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Endoplasmic Reticulum / chemistry*
  • Endoplasmic Reticulum / drug effects
  • Endoplasmic Reticulum / metabolism*
  • Endoplasmic Reticulum / ultrastructure
  • GTP Phosphohydrolases / metabolism*
  • Guanosine Triphosphate / metabolism
  • Guanosine Triphosphate / pharmacology
  • Hydrolysis / drug effects
  • Membrane Fusion
  • Membrane Transport Proteins / metabolism*
  • Membrane Transport Proteins / ultrastructure
  • Proteolipids / chemistry
  • Proteolipids / metabolism
  • Proteolipids / ultrastructure
  • Saccharomyces cerevisiae / cytology*
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae / ultrastructure
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Saccharomyces cerevisiae Proteins / ultrastructure
  • Vesicular Transport Proteins / metabolism*
  • Vesicular Transport Proteins / ultrastructure


  • Membrane Transport Proteins
  • Proteolipids
  • SEY1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Vesicular Transport Proteins
  • YOP1 protein, S cerevisiae
  • proteoliposomes
  • Guanosine Triphosphate
  • GTP Phosphohydrolases