Vps51p links the VFT complex to the SNARE Tlg1p

J Biol Chem. 2002 Dec 13;277(50):48318-24. doi: 10.1074/jbc.M209428200. Epub 2002 Oct 10.

Abstract

Intracellular membrane fusion requires the complex coordination of SNARE, rab/ypt, and rab effector function. In the yeast Saccharomyces cerevisiae, fusion of endosome-derived vesicles with the late Golgi depends on a cascade of protein-protein interactions that results in the recruitment to Golgi membranes of a conserved docking complex, VFT. This complex binds to Ypt6-GTP, which is necessary for its localization to the Golgi, and also to the SNARE Tlg1p. We show here that the VFT complex contains a fourth, previously uncharacterized, subunit, Vps51p (Ykr020w). Yeast cells lacking VPS51 have defects in vacuole morphology and recycling of the SNARE Snc1p to the plasma membrane, but still assemble a core VFT complex consisting of Vps52p, Vps53p, and Vps54p that localizes properly to the Golgi. Binding to Ypt6-GTP is a property of Vps52p. In contrast, binding to Tlg1p is mediated by a short sequence at the N terminus of Vps51p. Recent evidence suggests that components of a number of rab/ypt effector complexes share a common, distantly related helical coiled-coil motif. We show that each VFT subunit requires this coiled-coil motif for assembly into the complex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Membrane Proteins / metabolism*
  • Molecular Sequence Data
  • Protein Binding
  • SNARE Proteins
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Sequence Homology, Amino Acid
  • Vesicular Transport Proteins*

Substances

  • Membrane Proteins
  • SNARE Proteins
  • Saccharomyces cerevisiae Proteins
  • Vesicular Transport Proteins