FAD2-DGAT2Genes Coexpressed in EndophyticAspergillus fumigatusDerived from Tung Oilseeds

Abstract

Recent efforts to genetically engineer plants that contain fatty acid desaturases to produce valuable fatty acids have made only modest progress. Diacylglycerol acyltransferase 2 (DGAT2), which catalyzes the final step in triacylglycerol (TAG) assembly, might potentially regulate the biosynthesis of desired fatty acids in TAGs. To study the effects of tung tree (Vernicia fordii)vfDGAT2in channeling the desired fatty acids into TAG,vfDGAT2combined with the tung tree fatty acid desaturase-2 (vfFAD2) gene was co-introduced intoAspergillus fumigatus, an endophytic fungus isolated from healthy tung oilseed. Two transformants coexpressingvfFAD2andvfDGAT2showed a more than 6-fold increase in linoleic acid production compared to the originalA. fumigatusstrain, while a nearly 2-fold increase was found in the transformant expressing onlyvfFAD2. Our data suggest thatvfDGAT2plays a pivotal role in promoting linoleic acid accumulation in TAGs. This holds great promise for further genetic engineering aimed at producing valuable fatty acids.