Lipid Biotechnology Group

Global demand for plant oils is driving intense efforts to engineer oilseeds with improved oil content and novel oils with specific fatty acid profiles.

The Lipid Biotechnology Group is focused on addressing knowledge gaps in lipid metabolism and carbon flux to help improve and diversify seed oil products. Researchers will work to better understand triacylglycerol synthesis and its coordination with carbon turnover to improve oil content, generate novel oils, and increase the proportion of specific fatty acids such as erucic acid.

Increasing plant oil production

Triacylglycerol (TAG) synthesis

Triacylglycerols are oils that plants use to store energy and in some cases serve as edible oils. Genetic modification in rapeseed to increase oil content has won international recognition for the group. Altering the triacylglycerol (TAG) bioassembly pathway with a yeast gene (slc1-1 encoding a mutant LPAT) and two a plant gene encoding DGAT boosted oil production in the plants.

Further work aims to better understand the role of membrane-bound enzymes LPAT, DGAT and CPTase and their role in triacylglycerol bioassembly.

Contact: Dr. David Taylor at David.Taylor@nrc-cnrc.gc.ca
Phone: (306) 975-5268.

Oil for industry

Increasing erucic acid production in rapeseed

Plant oils are a source of fatty acids for industry. Erucic acid, for example, is used to make plastic films, nylon, lubricants and photographic supplies. In fact, there are more than 1,000 patented applications for erucic acid and its derivatives.

Commercial erucic acid is primarily derived from a plant called rapeseed. In rapeseed, an enzyme called LPAT is responsible for placing fatty acids into the middle of three spots on the glycerol backbone to form the oil. Rapeseed LPAT however lacks the ability to place erucic acid in one of the three available positions and so even high-yielding varieties of rapeseed are limited to about 45% erucic acid. The group has shown that an LPAT from cauliflower (Brassica oleracea) is capable of using erucic acid. Work to express this gene in rapeseed continues. Recent research has revealed that garden nasturtium (Tropaeolum majus) contains a fatty acid elongase (FAE) gene encoding an enzyme with the potential to greatly improve erucic acid proportions. When a gene encoding nasturtium FAE was inserted into thale cress (Arabidopsis thaliana), the plants produced 15 times the normal level of erucic acid in their seed – a world first. Thale cress, a model plant of plant biotechnology labs, is often used to test genetic modifications.

Work is underway to express the nasturtium FAE gene, (perhaps in conjunction with the cauliflower LPAT), in Brassica carinata, a type of mustard closely related to rapeseed. This crop already has a high erucic acid content, and can be genetically transformed relatively easily. It also grows well in dry climates like those on the Canadian Prairies and doesn't outcross with canola grown for food oil.

Contact: Dr. David Taylor at David.Taylor@nrc-cnrc.gc.ca
Phone: (306) 975-5268.

Oil production and plant performance

Glycerolipid biosynthesis and plant performance

In addition to being a major storage product in seeds, glycerolipid is a key component of cellular membrane systems. The main thrust of the research is to map out the glycerolipid biosythesis pathway – the step-by-step process that the plant uses to manufacture glycerolipid molecules. Understanding this pathway will shed light on lipid metabolism and other aspects of plant development and performance. Work with Arabidopsis thaliana is aimed at identifying genes encoding the enzymes and regulators of the glycerolipid pathway. Part of the work is to see how the actions of these enzymes and other regulatory factors change when the plant is under stress. Transgenic modification of the glycerolipid pathway is also pursued to examine potential impacts on plant performance.

Contact: Dr. Jitao Zou at Jitao.Zou@nrc-cnrc.gc.ca
Phone: (306) 975-5583.