Monodehyroascorbate reductase4 is required for seed storage oil hydrolysis and postgerminative growth in Arabidopsis
Eastmond, Peter J.. (2007) Monodehyroascorbate reductase4 is required for seed storage oil hydrolysis and postgerminative growth in Arabidopsis. Plant Cell, Vol.19 (No.4). pp. 1376-1387. ISSN 1040-4651Full text not available from this repository.
Official URL: http://dx.doi.org/10.1105/tpc.106.043992
Hydrogen peroxide is a major by-product of peroxisomal metabolism and has the potential to cause critical oxidative damage. In all eukaryotes, catalase is thought to be instrumental in removing this H2O2. However, plants also contain a peroxisomal membrane - associated ascorbate-dependent electron transfer system, using ascorbate peroxidase and monodehydroascorbate reductase (MDAR). Here, I report that the conditional seedling-lethal sugar-dependent2 mutant of Arabidopsis thaliana is deficient in the peroxisomal membrane isoform of MDAR (MDAR4). Following germination, Arabidopsis seeds rely on storage oil breakdown to supply carbon skeletons and energy for early seedling growth, and massive amounts of H2O2 are generated within the peroxisome as a by-product of fatty acid b-oxidation. My data suggest that the membrane-bound MDAR4 component of the ascorbate-dependent electron transfer system is necessary to detoxify H2O2, which escapes the peroxisome. This function appears to be critical to protect oil bodies that are in close proximity to peroxisomes from incurring oxidative damage, which otherwise inactivates the triacylglycerol lipase SUGAR-DEPENDENT1 and cuts off the supply of carbon for seedling establishment.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry
S Agriculture > SB Plant culture
Q Science > QH Natural history > QH301 Biology
|Divisions:||Faculty of Science > Life Sciences (2010- ) > Warwick HRI (2004-2010)|
|Journal or Publication Title:||Plant Cell|
|Publisher:||American Society of Plant Biologists|
|Number of Pages:||12|
|Page Range:||pp. 1376-1387|
|Access rights to Published version:||Restricted or Subscription Access|
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