www.checkbiotech.org ; www.raupp.info ; www.czu.cz

Vitamin E has found much use as a nutritional supplement and therapeutic
drug in humans. Some forms of it may be isolated from plants, where it is a
major antioxidant, but scientists still know little of what its function
might be if plants are placed under photo-oxidative stress, December 2005.

In the latest issue of Plant Cell, Michel Havaux and colleagues find that
?Vitamin E Protects against Photoinhibition and Photooxidative Stress in
Arabidopsis thaliana.? Using the weed, researchers were able to determine
how Vitamin E could protect the plant from destruction by light exposure.

Researchers studied Vitamin E mutants, named vte1 and vte2, which lack the
genes to synthesize the vitamin. When exposed to intense light conditions,
they found that the leaves of the mutants bleached, while whole, non-mutant
plants exposed to the same stress remained healthy. In extreme temperatures
and very high light conditions, however, both mutants and conventional
Arabidopsis plants were destroyed.

Through more experiments, researchers also found that Vitamin E preserves
plant photosystems from light inactivation, and protects cell membrane
lipids from light oxidation.

Subscribers to Plant Cell may read the complete article at:
[www.plantcell.org]

Other readers may access the abstract at:
[www.plantcell.org]

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