The Pep4p vacuolar proteinase contributes to the turnover of oxidized proteins but PEP4 overexpression is not sufficient to increase chronological lifespan in Saccharomyces cerevisiae

• Type: Article in International Scientific Journal
• Date: 2006

Authors

Marques, M (Author) Other; Mojzita, D (Author) Other; Amorim, MA (Author) Other; Almeida, T (Author) Other; Hohmann, S (Author) Other; Pedro Moradas Ferreira (Author) ICBAS; Vitor Costa (Author) ICBAS

Journal

Title: Microbiology

Vol. 152

Pages: 3595-3605

ISSN: 1350-0872

Publisher: Microbiological Society

Indexing

ISI Web of Knowledge - 35 Citations

Scopus - 47 Citations

Other information

Authenticus ID: P-004-FWS

DOI: 10.1099/mic.0.29040-0

Abstract (EN): Turnover of damaged molecules is considered to play a key role in housekeeping of cells exposed to oxidative stress, and during the progress of ageing. In this work, global changes in the transcriptome were analysed during recovery of yeast cells after H2O2 stress. Regarding induced genes, those associated with protein fate were the most significantly over-represented. In addition to genes encoding subunits of the 20S proteasome, genes related to vacuolar proteolysis (PEP4 and LAP4), protein sorting into the vacuole, and vacuolar fusion were found to be induced. The upregulation of PEP4 gene expression was associated with an increase in Pep4p activity. The induction of genes related to proteolysis was correlated with an increased protein turnover after H2O2-induced oxidation. Furthermore, protein degradation and the removal of oxidized proteins decreased in Pep4p-deficient cells. Pep4p activity also increased during chronological ageing, and cells lacking Pep4p displayed a shortened lifespan associated with higher levels of carbonylated proteins. PEP4 overexpression prevented the accumulation of oxidized proteins, but did not increase lifespan. These results indicate that Pep4p is important for protein turnover after oxidative damage; however, increased removal of oxidized proteins is not sufficient to enhance lifespan.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11