Plastochromanol-8 and tocopherols are essential lipid-soluble antioxidants during seed desiccation and quiescence in Arabidopsis.
Proc Natl Acad Sci U S A
; 107(41): 17815-20, 2010 Oct 12.
Article
in En
| MEDLINE
| ID: mdl-20837525
ABSTRACT
Given their essential role as vitamin E, tocopherols and tocotrienols have been studied extensively in animals and plants. In contrast, our understanding of the function of plastochromanol-8 (PC-8), a third type of tocochromanol with a longer side chain, is very limited despite the wide distribution of PC-8 in the plant kingdom, including species consumed by humans. To investigate PC-8 function in vivo, we combined the Arabidopsis vte1 mutation that eliminates tocopherols and PC-8 and causes the accumulation of 2,3-dimethyl-6-phytyl-1,4-benzoquinol (DMPBQ), a redox-active tocopherol precursor, and the vte2 mutation that eliminates tocopherols without affecting PC-8. The vte2 vte1 double mutant lacks tocopherols, PC-8, and DMPBQ, and exhibits the most severe physiological and biochemical phenotypes of any tocochromanol-affected genotype isolated to date, most notably a severe seedling developmental phenotype associated with massive lipid oxidation initiated during seed desiccation and amplified during seed quiescence. In contrast, the presence of PC-8 in vte2 suppresses or attenuates all of the developmental and biochemical phenotypes observed in vte2 vte1, demonstrating that PC-8 is a lipid antioxidant in vivo. Finally, the low relative fitness of vte2 vte1 demonstrates that tocopherols and PC-8 are in vivo lipid antioxidants essential for seed plant survival.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Seeds
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Vitamin E
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Chromans
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Arabidopsis
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Tocopherols
/
Antioxidants
Language:
En
Journal:
Proc Natl Acad Sci U S A
Year:
2010
Document type:
Article
Affiliation country:
United States
Country of publication:
EEUU
/
ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
/
USA