Yeast Mon1p/Aut12p Functions in Vacuolar Fusion of Autophagosomes and CVT-Vesicles

FEBS Lett. 2002 Oct 23;530(1-3):174-80. doi: 10.1016/s0014-5793(02)03456-7.


Here we identify Mon1p as being essential for the cvt-pathway and autophagy. Thus, mon1Delta cells are impaired in proaminopeptidase I maturation and homozygous diploid mon1Delta cells do not sporulate. Quantitative autophagy measurements suggest a complete autophagy block. The autophagosomal marker protein GFP-Aut7p accumulates in mon1Delta cells at punctate structures outside the vacuole. Furthermore, proaminopeptidase I accumulates in mon1Delta cells in a proteinase-protected form. Our data demonstrate that mon1Delta cells are defective in the fusion of cvt-vesicles and autophagosomes with the vacuole. Consistent with this, GFP-Mon1p localizes to the cytosol and to punctate structures within the cytosol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminopeptidases / metabolism
  • Autophagy
  • Base Sequence
  • DNA Primers
  • Fungal Proteins / metabolism*
  • Phagosomes / enzymology
  • Phagosomes / physiology*
  • Protein Precursors / metabolism
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / metabolism*
  • Vacuoles / enzymology
  • Vacuoles / physiology*


  • DNA Primers
  • Fungal Proteins
  • Protein Precursors
  • Aminopeptidases
  • proaminopeptidase I