Arachis hypogaea monoacylglycerol lipase AhMAGL3b participates in lipid metabolism

Abstract

Abstract Background Monoacylglycerol lipase (MAGL) belongs to the serine hydrolase family; it catalyzes MAG to produce glycerol and free fatty acids (FFAs), which is the final step in triacylglycerol (TAG) hydrolysis. The effects of MAGL on comprehensive lipid metabolism and plant growth and development have not been elucidated, especially in Arachis hypogaea, an important oil crop. Results Herein, AhMAGL3b encoding a protein with both hydrolase and acyltransferase regions, a member of MAGL gene family, was cloned and overexpressed in Arabidopsis thaliana. A total of 9 homozygous T3 generation transgenic lines were obtained. Compared with wild type (WT), overexpression (OE) of AhMAGL3b had no obvious growth inhibition by investigation of agronomic traits, including growth and photosynthetic parameters. The leaf fatty acid (FA) content was increased by 12.1–27.4% in AhMAGL3b-OE lines, while seed oil content was decreased by 10.7–17.3%. Furthermore, the overexpression of AhMAGL3b resulted in higher soluble sugar and starch content, and lower total soluble protein content in both leaves and seeds. Additionally, during seed germination, AhMAGL3b-OE seeds were more dormant than that of WT and the sensitivity to abscisic acid (ABA) treatment was decreased. Conclusions Taken together, our results indicate that AhMAGL3b is involved in homeostasis among carbohydrates, lipids and protein in A. hypogaea.

Keywords

• Arachis hypogaea
• MAGL
• TAG metabolism
• Germination
• ABA