Copper chaperone-dependent and -independent activation of three copper-zinc superoxide dismutase homologs localized in different cellular compartments in Arabidopsis
Journal
Plant Physiology
Journal Volume
158
Journal Issue
2
Pages
737
Date Issued
2012-02-01
Author(s)
Abstract
Superoxide dismutases (SODs) are important antioxidant enzymes that catalyze the disproportionation of superoxide anion to oxygen and hydrogen peroxide to guard cells against superoxide toxicity. The major pathway for activation of copper/zinc SOD (CSD) involves a copper chaperone for SOD (CCS) and an additional minor CCS-independent pathway reported in mammals. We characterized the CCS-dependent and -independent activation pathways for three CSDs localized in different cellular compartments in Arabidopsis (Arabidopsis thaliana). The main activation pathway for CSD1 in the cytoplasm involved a CCS-dependent and -independent pathway, which was similar to that for human CSD. Activation of CSD2 in chloroplasts depended totally on CCS, similar to yeast (Saccharomyces cerevisiae) CSD. Peroxisome-localized CSD3 via a CCS-independent pathway was similar to nematode (Caenorhabditis elegans) CSD in retaining activity in the absence of CCS. In Arabidopsis, glutathione played a role in CCS-independent activation, as was reported in humans, but an additional factor was required. These findings reveal a highly specific and sophisticated regulation of CSD activation pathways in planta relative to other known CCS-independent activation. © 2011 American Society of Plant Biologists.
Other Subjects
Arabidopsis; Arabidopsis thaliana; Caenorhabditis elegans; Mammalia; Saccharomyces cerevisiae
Publisher
AMER SOC PLANT BIOLOGISTS
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
737.full.pdf
Size
892.28 KB
Format
Adobe PDF
Checksum
(MD5):9ad8cf25792101d75bd859b7ab9ebccc