Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/27/2010
Publication Date: 9/17/2010
Citation: Chen, G.Q. 2010. Develop a New Lesquerella fendleri Crop for Castor Oil Production. Association for the Advancement of Industrial Crops 22nd Annual Meeting, 2010 New Crops: Exploring Diversity, Preserving our Future, Fort Collins, CO, September 18 to 22, 2010.
Technical Abstract: Seed oil of Lesquerella fendleri contains a valuable hydroxy fatty acid (HFA), lesquerolic acid (20:1OH). The conventional source of HFA is ricinoleic acid (18:1OH) from castor seeds. Ricinoleic acid and its derivatives are used as raw materials for numerous industrial products, such as lubricants, plasticizers and surfactants. The production of castor oil, however, is hampered by the presence of the toxin ricin and hyper-allergic 2S albumins in its seed. L. fendleri, on the other hand, does not have such biological toxic compounds, thus its oil represents an alternative source of HFA. Lesquerolic acid is derived by a 2 carbon elongation of 18:1OH. By suppressing the elongation step through genetic engineering, it is possible to generate a new L. fendleri crop that could produce 18:1OH. To facilitate such a genetic approach, we investigated regulatory mechanisms underlying HFA synthesis. We found three HFAs accumulated consecutively, with initial appearance of 18:1OH, followed by 20:1OH and auricolate (20:2OH). Only 20:1OH reached a predominant level of 55%. Using real-time PCR, we quantified the transcript level of three key lipid genes involved in HFA synthesis, LfFAH (oleate 12-hydroxylase), LfKCS3 (3-ketoacyl-CoA synthase) and LfFen1 (oleate 12-desaturase). We found the synthesis of 20:1OH regulated mainly by gene transcription of LfKCS3. These results will advance our understanding of regulatory mechanisms underlying synthesis and accumulation of HFAs, which are useful to the development of an 18:1OH-producing L. fendleri crop through genetic engineering.