Format

Send to

Choose Destination
See comment in PubMed Commons below
Ann Bot. 2013 May;111(5):839-47. doi: 10.1093/aob/mct045. Epub 2013 Feb 28.

Class III peroxidases are activated in proanthocyanidin-deficient Arabidopsis thaliana seeds.

Author information

1
School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China.

Abstract

BACKGROUND AND AIMS:

It has previously been shown that proanthocyanidins (PAs) in the seed coat of Arabidopsis thaliana have the ability to scavenge superoxide radicals (O2(-)). However, the physiological processess in PA-deficit seeds are not clear. It is hypothesized that there exist alternative ways in PA-deficient seeds to cope with oxidative stress.

METHODS:

The content of hydrogen peroxide (H2O2) and its relevance to the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidases was investigated in both wild-type and PA-deficit mutant seeds. A biochemical staining approach was used to detect tissue localizations of peroxidase activities in PA-deficit mutant seeds.

KEY RESULTS:

PA-deficient mutants possess significantly lower levels of H2O2 than the wild-type, despite their higher accumulation of superoxide radicals. Screening of the key antioxidant enzymes revealed that peroxidase activity was significantly over-activated in mutant seeds. This high peroxidase activity was mainly confined to the seed coat zone. Interestingly, neither ascorbate peroxidase nor glutathione peroxidase, just the guaiacol peroxidases (class III peroxidases), was specifically activated in the seed coat. However, no significant difference in peroxidase activity was observed in embryos of either mutants or the wild-type, although gene expressions of several candidate peroxidases were down-regulated in the embryos of PA-deficient seeds.

CONCLUSIONS:

The results suggest that enhanced class III peroxidase activity in the seed coat of PA-deficient mutants is an adaptive strategy for seed development and survival.

PMID:
23448691
PMCID:
PMC3631330
DOI:
10.1093/aob/mct045
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center