Rat peptide methionine sulphoxide reductase: cloning of the cDNA, and down-regulation of gene expression and enzyme activity during aging

Citation
I. Petropoulos et al., Rat peptide methionine sulphoxide reductase: cloning of the cDNA, and down-regulation of gene expression and enzyme activity during aging, BIOCHEM J, 355, 2001, pp. 819-825
Citations number
36
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL JOURNAL
ISSN journal
02646021 → ACNP
Volume
355
Year of publication
2001
Part
3
Pages
819 - 825
Database
ISI
SICI code
0264-6021(20010501)355:<819:RPMSRC>2.0.ZU;2-4
Abstract
Peptide methionine sulphoxide reductase (PRMSR, EC 1.8,4,6), the msrA or pm sR gene product, is a ubiquitous enzyme catalysing the reduction of methion ine sulphoxide to methionine in proteins. Decreased expression and/or activ ity of the PMSR with age could explain, at least in part, the accumulation of oxidized protein observed upon aging. In test this hypothesis, the rat p msR cDNA was cloned and sequenced. The recombinant protein was expressed, i ts catalytic activity checked with a synthetic substrate and polyclonal ant ibodies were raised against recombinant PMSR. The expression of the pmsR ge ne and protein as well as its catalytic activity wire then analysed as a fu nction of age in the rat brain and in two organs that express the most PMSR , liver and kidney. It appears that pmsR gene expression decreases with age in liver and kidney as early as 18 months, whereas protein level and prote in activity are reduced in the three organs at the very end of the life of the rat (26 months). These results suggest that the down-regulation of PMSR can contribute to the accumulation of oxidized protein that has been assoc iated with the aging process.