Ordering the final events in yeast exocytosis

J Cell Biol. 2000 Oct 16;151(2):439-52. doi: 10.1083/jcb.151.2.439.

Abstract

In yeast, assembly of exocytic soluble N-ethylmaleimide-sensitive fusion protein (NSF) attachment protein receptor (SNARE) complexes between the secretory vesicle SNARE Sncp and the plasma membrane SNAREs Ssop and Sec9p occurs at a late stage of the exocytic reaction. Mutations that block either secretory vesicle delivery or tethering prevent SNARE complex assembly and the localization of Sec1p, a SNARE complex binding protein, to sites of secretion. By contrast, wild-type levels of SNARE complexes persist in the sec1-1 mutant after a secretory block is imposed, suggesting a role for Sec1p after SNARE complex assembly. In the sec18-1 mutant, cis-SNARE complexes containing surface-accessible Sncp accumulate in the plasma membrane. Thus, one function of Sec18p is to disassemble SNARE complexes on the postfusion membrane.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphatases*
  • Carrier Proteins / metabolism
  • Cell Membrane / metabolism
  • Cell Polarity
  • Exocytosis*
  • Fungal Proteins / metabolism*
  • GTP-Binding Proteins / metabolism
  • Guanine Nucleotide Exchange Factors
  • Membrane Fusion*
  • Membrane Proteins / metabolism*
  • Models, Biological
  • Munc18 Proteins
  • N-Ethylmaleimide-Sensitive Proteins
  • Nerve Tissue Proteins / metabolism
  • Qa-SNARE Proteins
  • R-SNARE Proteins
  • SNARE Proteins
  • Saccharomyces cerevisiae Proteins*
  • Transport Vesicles / metabolism
  • Vesicular Transport Proteins*
  • Yeasts

Substances

  • Carrier Proteins
  • Fungal Proteins
  • Guanine Nucleotide Exchange Factors
  • Membrane Proteins
  • Munc18 Proteins
  • Nerve Tissue Proteins
  • Qa-SNARE Proteins
  • R-SNARE Proteins
  • SEC2 protein, S cerevisiae
  • SNARE Proteins
  • SNC1 protein, S cerevisiae
  • SNC2 protein, S cerevisiae
  • SSO1 protein, S cerevisiae
  • SSO2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Vesicular Transport Proteins
  • Adenosine Triphosphatases
  • GTP-Binding Proteins
  • SEC18 protein, S cerevisiae
  • N-Ethylmaleimide-Sensitive Proteins