PEP4 gene of Saccharomyces cerevisiae encodes proteinase A, a vacuolar enzyme required for processing of vacuolar precursors.

TitlePEP4 gene of Saccharomyces cerevisiae encodes proteinase A, a vacuolar enzyme required for processing of vacuolar precursors.
Publication TypeJournal Article
Year of Publication1986
AuthorsAmmerer G, Hunter CP, Rothman JH, Saari GC, Valls LA, Stevens TH
JournalMol Cell Biol
Volume6
Issue7
Pagination2490-9
Date Published1986 Jul
ISSN0270-7306
KeywordsAmino Acid Sequence, Aspartic Acid Endopeptidases, Base Sequence, DNA Restriction Enzymes, Endopeptidases, Genes, Genetic Complementation Test, Organoids, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Vacuoles
Abstract

The proteinase A structural gene of Saccharomyces cerevisiae was cloned by using an immunological screening procedure that allows detection of yeast cells which are aberrantly secreting vacuolar proteins (J. H. Rothman, C. P. Hunter, L. A. Valls, and T. H. Stevens, Proc. Natl. Acad. Sci. USA, 83:3248-3252, 1986). A second cloned gene was obtained on a multicopy plasmid by complementation of a pep4-3 mutation. The nucleotide sequences of these two genes were determined independently and were found to be identical. The predicted amino acid sequence of the cloned gene suggests that proteinase A is synthesized as a 405-amino-acid precursor which is proteolytically converted to the 329-amino-acid mature enzyme. Proteinase A shows substantial homology to mammalian aspartyl proteases, such as pepsin, renin, and cathepsin D. The similarities may reflect not only analogous functions but also similar processing and intracellular targeting mechanisms for the two proteins. The cloned proteinase A structural gene, even when it is carried on a single-copy plasmid, complements the deficiency in several vacuolar hydrolase activities that is observed in a pep4 mutant. A strain carrying a deletion in the genomic copy of the gene fails to complement a pep4 mutant of the opposite mating type. Genetic linkage data demonstrate that integrated copies of the cloned proteinase A structural gene map to the PEP4 locus. Thus, the PEP4 gene encodes a vacuolar aspartyl protease, proteinase A, that is required for the in vivo processing of a number of vacuolar zymogens.

Alternate JournalMol. Cell. Biol.
PubMed ID3023936
PubMed Central IDPMC367803