pro-vitamin A content in rice
Scientists from Syngenta reported improving the nutritional value of Golden Rice through increased pro-vitamin A content. Golden rice is a variety of rice engineered to produce beta-carotene (pro-vitamin A) to help combat vitamin A deficiency. They were ale to increase total carotenoids by up to 23-fold compared to the original Golden Rice and a preferential accumulation of beta-carotene.
Jacqueline Paine and colleagues noted in an article in Nature Biotechnology that the daffodil gene encoding phytoene synthase (psy), one of two genes used to develop Golden Rice, was the limiting step in beta-carotene accumulation. Through systematic testing of other plant psys, they were able to identify a psy from maize that substantially increase carotenoid accumulation in a model plant system. They were then able to develop Golden Rice 2 by introducing this psy in combination with the Erwinia uredovora carotene desaturase used to generate the original Golden Rice.
For more information email co-author Rachel Drake at Rachel.email@example.com or read the March 27, 2005 article at Nature Biotechnology.