Molecular architecture and functional model of the complete yeast ESCRT-I heterotetramer

Cell. 2007 May 4;129(3):485-98. doi: 10.1016/j.cell.2007.03.016. Epub 2007 Apr 19.


The endosomal sorting complex required for transport-I (ESCRT-I) complex, which is conserved from yeast to humans, directs the lysosomal degradation of ubiquitinated transmembrane proteins and the budding of the HIV virus. Yeast ESCRT-I contains four subunits, Vps23, Vps28, Vps37, and Mvb12. The crystal structure of the heterotetrameric ESCRT-I complex reveals a highly asymmetric complex of 1:1:1:1 subunit stoichiometry. The core complex is nearly 18 nm long and consists of a headpiece attached to a 13 nm stalk. The stalk is important for cargo sorting by ESCRT-I and is proposed to serve as a spacer regulating the correct disposition of cargo and other ESCRT components. Hydrodynamic constraints and crystallographic structures were used to generate a model of intact ESCRT-I in solution. The results show how ESCRT-I uses a combination of a rigid stalk and flexible tethers to interact with lipids, cargo, and other ESCRT complexes over a span of approximately 25 nm.

Publication types

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

MeSH terms

  • Cell Membrane / chemistry
  • Cell Membrane / metabolism
  • Crystallography, X-Ray
  • Endosomal Sorting Complexes Required for Transport
  • Endosomes / chemistry*
  • Endosomes / metabolism
  • Models, Molecular
  • Molecular Structure
  • Multiprotein Complexes / chemistry
  • Multiprotein Complexes / metabolism
  • Protein Conformation
  • Protein Structure, Quaternary
  • Saccharomyces cerevisiae / chemistry*
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Vesicular Transport Proteins / chemistry*
  • Vesicular Transport Proteins / metabolism


  • Endosomal Sorting Complexes Required for Transport
  • Multiprotein Complexes
  • Mvb12 protein, S cerevisiae
  • SRN2 protein, S cerevisiae
  • STP22 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • VPS28 protein, S cerevisiae
  • Vesicular Transport Proteins

Associated data

  • PDB/2P22