Details

Autor(en) / Beteiligte

• Van Eenennaam, Alison L.
• Lincoln, Kim
• Durrett, Timothy P.
• Valentin, Henry E.
• Shewmaker, Christine K.
• Thorne, Greg M.
• Jiang, Jian
• Baszis, Susan R.
• Levering, Charlene K.
• Aasen, Eric D.
• Hao, Ming
• Stein, Joshua C.
• Norris, Susan R.
• Last, Robert L.

Titel

Engineering Vitamin E Content: From Arabidopsis Mutant to Soy Oil

Ist Teil von

• The Plant cell, 2003-12, Vol.15 (12), p.3007-3019

Ort / Verlag

England: American Society of Plant Biologists

Erscheinungsjahr

2003

Quelle

MEDLINE

Beschreibungen/Notizen

• We report the identification and biotechnological utility of a plant gene encoding the tocopherol (vitamin E) biosynthetic enzyme 2-methyl-6-phytylbenzoquinol methyltransferase. This gene was identified by map-based cloning of the Arabidopsis mutation vitamin E pathway gene3-1 (vte3-1), which causes increased accumulation of δ-tocopherol and decreased γ-tocopherol in the seed. Enzyme assays of recombinant protein supported the hypothesis that At-VTE3 encodes a 2-methyl-6-phytylbenzoquinol methyltransferase. Seed-specific expression of At-VTE3 in transgenic soybean reduced seed δ-tocopherol from 20 to 2%. These results confirm that At-VTE3 protein catalyzes the methylation of 2-methyl-6-phytylbenzoquinol in planta and show the utility of this gene in altering soybean tocopherol composition. When At-VTE3 was coexpressed with At-VTE4 (γ-tocopherol methyltransferase) in soybean, the seed accumulated to >95% α-tocopherol, a dramatic change from the normal 10%, resulting in a greater than eightfold increase of α-tocopherol and an up to fivefold increase in seed vitamin E activity. These findings demonstrate the utility of a gene identified in Arabidopsis to alter the tocopherol composition of commercial seed oils, a result with both nutritional and food quality implications.