| 摘要 |
Disclosed is are gene sequences encoding gamma-tocopherol methyltransferases from photosynthetic organisms. The enzyme gamma-tocopherol methyltransferase catalyzes the methylation of gamma-tocopherol to yield alpha-tocopherol, the most bioactive species of tocopherol. gamma-tocopherol methyltransferase is believed to be involved in regulating the relative amounts of the various tocopherols present in photosynthetic organisms. By introducing a genetic construct having a gamma-tocopherol methyltransferase coding sequence placed under the control of a plant promoter into a plant, transgenic plants can be made having altered gamma-tocopherol methyltransferase expression, to effect dramatic changes in the tocopherol profile of the plant. Transgenic plants can be made that have alpha-tocopherol as the predominant tocopherol in their seeds and oils. |
