Discovery of plant proteins may boost agricultural yields and biofuel production
Plant oils are composed primarily of triglycerides, formed by linking together three fatty acid molecules, and are stored mostly in seeds, where they are used for energy during germination. Seeds are crucial sources of oils for nutrition, flavoring and industrial applications, such as the manufacturing of soap and cosmetics and for biofuels. With growing concerns about global climate change and petroleum security, producing biofuels for use in transportation and energy generation is a burgeoning industry.
Now, scientists at Salk and Iowa State University, led by Salk professor Joseph Noel, have discovered a family of plant proteins that play a role in the production of seed oils.
Scoring a rare scientific hat trick, the researchers identified three related proteins in thale cress plants (Arabidopsis thaliana) that regulate the metabolism of fatty acids, chemical components of all cell membranes and vegetable oils. They found that the proteins, FAP1, FAP2 and FAP3, bind fatty acids, including the major plant omega-3 fatty acid, an important nutritional component found in certain seeds.
"They say a picture is worth a thousand words, and that is certainly the case for these FAPs," says Gordon Louie, a researcher in Noel's laboratory, who determined the threedimensional arrangement of the FAPs holding onto their fatty acid cargo.
The proteins were found in the chloroplasts, the site of fatty acid production and photosynthesis in plant cells. This suggested that these proteins play a role in the metabolism of fatty acids and thus in the production of fatty acids for plant membranes and oils.
The findings, reported in Nature, may lead to the development of crops yielding higher qualities and quantities of oils, helping to address growing demands for food and fuel and the consequent environmental pressures on the world's ecosystems.
"This work has major implications for modulating the fatty acid profiles of plants, which is terribly important, not only to sustainable food production and nutrition but now to biorenewable chemicals and fuels," says Joseph Noel.