ATG23, a novel gene required for maturation of proaminopeptidase I, but not for autophagy.

Abstract

In rich media proaminopeptidase I is targeted to the vacuole via the Cvt pathway and during starvation via autophagy. We here identify Atg23 (Ylr431c), a protein of so far unknown function, as a novel component essential for proaminopeptidase I maturation under non-starvation conditions. Maturation of proaminopeptidase I takes place in starved atg23Delta cells. Selective vacuolar targeting of the autophagosomal marker GFP-Aut7 and the accumulation of autophagic bodies during starvation in the presence of phenylmethylsulfonyl fluoride suggest that autophagy occurs in atg23Delta cells but at a reduced rate. In atg23Delta cells mature vacuolar carboxypeptidase Y is present and accumulation of quinacrine suggests no significant defect in vacuolar acidification. Furthermore, growth of atg23Delta cells on nitrocellulose detects no significant secretion of carboxypeptidase Y.

• Authors: Khuyen Meiling-Wesse, Fotini Bratsika, Michael Thumm
• Journal: FEMS yeast research (FEMS Yeast Res) Vol. 4 Issue 4-5 Pg. 459-65 (Jan 2004) ISSN: 1567-1356 [Print] England
• PMID: 14734026 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Atg23 protein, S cerevisiae
• Autophagy-Related Proteins
• DNA Primers
• Protein Precursors
• Saccharomyces cerevisiae Proteins
• Endopeptidases
• Aminopeptidases
• proaminopeptidase I

Topics

• Aminopeptidases (genetics)
• Autophagy
• Autophagy-Related Proteins
• Base Sequence
• DNA Primers
• Endopeptidases (metabolism)
• Protein Precursors (genetics)
• Saccharomyces cerevisiae (enzymology, genetics, growth & development)
• Saccharomyces cerevisiae Proteins (genetics)
• Vacuoles (enzymology)