Development of ultra-high erucic acid oil in the industrial oil crop Crambe abyssinica.
Erucic acid (22 : 1) is a major feedstock for the oleochemical industry. In this study, a gene stacking strategy was employed to develop transgenic Crambe abyssinica lines with increased 22 : 1 levels. Through integration of the LdLPAAT, BnFAE1 and CaFAD2-RNAi genes into the crambe genome, confirmed by Southern blot and qRT-PCR, the average levels of 18 : 1, 18 : 2 and 18 : 3 were markedly decreased and that of 22 : 1 was increased from 60% in the wild type to 73% in the best transgenic line of T4 generation. In single seeds of the same line, the 22 : 1 level could reach 76.9%, an increase of 28.0% over the wild type. The trierucin amount was positively correlated to 22 : 1 in the transgenic lines. Unlike high erucic rapeseed, the wild-type crambe contains 22 : 1 in the seed phosphatidylcholine and in the sn-2 position of triacylglycerols (5% and 8%, respectively). The transgenic line with high 22 : 1 had decreased 22 : 1 level in phosphatidylcholine, and this was negatively correlated with the 22 : 1 level at the sn-2 position of TAG. The significances of this study include (i) achieving an unprecedented level of 22 : 1 in an oil crop; (ii) disclosing mechanisms in the channelling of a triacylglycerol-specific unusual fatty acid in oil seeds; (iii) indicating potential limiting factors involved in the erucic acid biosynthesis and paving the way for further increase of this acid and (iv) development of an added value genetically modified oil crop having no risk of gene flow into feed and food crops.
Department of Plant Breeding and Biotechnology, Swedish University of Agricultural Sciences, Sweden.
Xueyuan
X
Li
Eibertus N
EN
van Loo
Jens
J
Gruber
Jing
J
Fan
Rui
R
Guan
Margrit
M
Frentzen
Sten
S
Stymne
Li-Hua
LH
Zhu
D000123:Acetyltransferases / Q000235:genetics / Q000378:metabolism; D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D001709:Biotechnology / Q000379:methods*; D029688:Brassica napus / Q000201:enzymology; D031218:Crambe Plant / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D018556:Crops, Agricultural / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D004883:Erucic Acids / Q000378:metabolism*; D044943:Fatty Acid Desaturases / Q000235:genetics / Q000378:metabolism; D000081031:Fatty Acid Elongases; D018506:Gene Expression Regulation, Plant; D006824:Hybridization, Genetic; D007219:Industrial Oils / Q000032:analysis*; D040582:Inheritance Patterns / Q000235:genetics; D010713:Phosphatidylcholines / Q000378:metabolism; D010938:Plant Oils / Q000378:metabolism*; D030821:Plants, Genetically Modified; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics; D014170:Transformation, Genetic; D019076:Transgenes / Q000235:genetics; D014280:Triglycerides / Q000378:metabolism
D004883:Erucic Acids; D010713:Phosphatidylcholines; D010938:Plant Oils; D012333:RNA, Messenger; D014280:Triglycerides; D044943:Fatty Acid Desaturases; D000217:Acyltransferases; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases; C030774:trierucate