To improve the health-promoting effects of plant oils through metabolic engineering in oilseed plants

	Identify genes responsible for the modification of oleic acid and down-regulate them in developing oilseeds
	Characterize the resulting plants oils for their functional and nutritional properties
	Coordinate the large-scale production of the novel oilseed crop
	Identify genes that control the synthesis of long chain omega-3 fatty acids (LCPUFAs) from marine plankton
	Introduce these genes into developing oilseeds to reconstruct the LCPUFA metabolic pathway
	Fine tune the pathway by optimizing co-ordinate expression of the pathway enzymes for optimal LCPUFA production

	Low linolenic soybean oil in commercial production
	High oleic soybean oil in early stages of commercial production
	Soybeans with a high abundance of LCPUFAs in the seed oil demonstrated

	Potential elimination of trans fatty acids from the US diet and resulting posiive effect on coronary health
	Potential production of a high quality substitute for fish oil fatty acids from a sustainable source with multiple and significant health benefits for the US population

Abstract:

Genetic engineering of oilseed crops has enabled modifications of plant oils which were not feasible by more traditional techniques. These modifications have resulted in oils that are healthier and with improved functional properties. Initial approaches  focused on changing the existing ratios of the fatty acids in the plant triacylglycerol. The result has been the production of plant oils with a greatly reduced  ratio of omega-6 to omega-3 fatty acids. In addition to improving the balance of polyunsaturated acids, lowering the saturated fat content and increasing the content of the health-promoting oleic acid (a major component of olive oil), high oleic oil is oxidatively stable and can be used as a substitute for partially hygrogenated oils in many foods, thus helping eliminate undesirable  trans fatty acids from the human diet. Production of such oils has the potential to reach several hundred million pounds per year in the US and could replace a significant proportion of the vegetable oil currently consumed.  More recent efforts to mine the biodiversity of the plant and microbe kingdoms has uncovered  new genes which can be used to produce novel fatty acids in plant oils.  For example, it has been possible to reconstruct,  in soybean seeds, the metabolic pathways from marine plankton that are responsible for the production of very long chain omega-3 polyunsaturated fatty acids. This could lead to the sustainable production of high quality omega-3 fatty acids in oilseed crops. While the potential total production of such oils is a fraction of that of high oleic oils, the value of the oil and its potential to positively effect human health is much greater.

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