Editors' ChoiceRedox Regulation

Peroxide Signaling and Antioxidant Defense

Science's STKE  27 Apr 2004:
Vol. 2004, Issue 230, pp. tw153-TW153
DOI: 10.1126/stke.2302004TW153

Cells have robust antioxidant defense systems to protect them against reactive oxygen and nitrogen species. However, in eukaryotes, hydrogen peroxide is also a signaling molecule, and the enzymes that reduce peroxides, the peroxiredoxins (Prxs), can be inactivated by overoxidation of the catalytic center to allow signaling. Budanov et al. show that the sestrins, a family of proteins whose expression is modulated by p53, are required for regeneration of active Prxs. Sestrins contain a predicted redox active domain that is homologous to AhpD, the enzyme that catalyzes reduction of bacterial Prx. However, whereas AhpD is a disulfide reductase, sestrins are cysteine sulfinyl reductases.

A. V. Budanov, A. A. Sablina, E. Feinstein, E. V. Koonin, P. M. Chumakov, Regeneration of peroxiredoxins by p53-regulated sestrins, homologs of bacterial AhpD. Science 304, 596-600 (2004). [Abstract] [Full Text]