Modification of the fatty acid composition in Arabidopsis and maize seeds using a stearoyl-acyl carrier protein desaturase-1 (ZmSAD1) gene

BMC Plant Biology

Research Article

Jieyun Hu¹  Jiansheng Li¹  Min Huang²  Hewei Du³ 

[1] China Agricultural University, National Maize Improvement Center of China, 100193, Beijing, Peoples’s Republic of China;College of Life Science, Yangtze University, 434025, Jingzhou, Hubei, Peoples’s Republic of China;College of Life Science, Yangtze University, 434025, Jingzhou, Hubei, Peoples’s Republic of China;Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, 434025, Jingzhou, Peoples’s Republic of China;

关键词: Zea mays;    Arabidopsis;    Stearoyl-acyl carrier protein desaturase;    Oil engineering;    Stearic acid;    Oleic oil;   

DOI  :  10.1186/s12870-016-0827-z

 received in 2016-04-21, accepted in 2016-06-07,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundStearoyl-acyl carrier protein desaturase (SAD) is a key enzyme that catalyses the conversion of stearoyl-acyl carrier protein (ACP) to oleoyl-ACP, a precursor for the biosynthesis of polyunsaturated fatty acids. ZmSAD1 (GenBank: KU949326) is a major QTL for stearic acid content in maize seeds. To investigate the biological function and the application potential of maize ZmSAD1 in oil biosynthesis, we isolated the full-length ZmSAD1 cDNA from maize B73 and overexpressed it in Arabidopsis and maize.ResultsUnder seed-specific overexpression of ZmSAD1 in Arabidopsis, the stearic acid content and the ratio of saturated to unsaturated fatty acids in the seeds were significantly decreased relative to those in the control. Conversely, in transgenic ZmSAD1 RNAi Arabidopsis seeds, the contents of stearic acid and long-chain saturated acids and the ratio of saturated to unsaturated fatty acids were significantly increased; in addition, the oleic acid content was significantly decreased. More importantly, transgenic ZmSAD1 maize that expressed high levels of ZmSAD1 in its mature seeds showed reduced stearic acid content (1.57 %) and a lower saturated to unsaturated fatty acid ratio (20.40 %) relative to those (1.64 % and 20.61 %, respectively) of the control. Conversely, down-regulation of ZmSAD1 in maize resulted in increased levels of stearic acid (1.78 %), long-chain saturated acids (0.85 %) and the ratio of saturated to unsaturated fatty acids (21.54 %) relative to those (1.64 %, 0.74 %, and 20.61 %, respectively) of the control, whereas the oleic acid (32.01 %) level was significantly decreased relative to that (32.68 %) of the control.ConclusionsOur work demonstrates that the contents of stearic acid, oleic acid, and long-chain saturated acids, and the ratio of saturated to unsaturated fatty acids, are modified in maize seeds by seed-specific overexpression or down-regulation of ZmSAD1. Therefore, the ZmSAD1 gene is a useful tool for engineering the seed oil composition in maize and other crops.

【 授权许可】

CC BY   
© The Author(s). 2016