Overexpression of Type 1 and 2 Diacylglycerol Acyltransferase Genes (JcDGAT1 and JcDGAT2) Enhances Oil Production in the Woody Perennial Biofuel Plant Jatropha curcas

Abstract

Diacylglycerol acyltransferase (DGAT) is the only enzyme that catalyzes the acyl-CoA-dependent acylation of sn-1, 2-diacylglycerol (DAG) to form triacylglycerol (TAG). The two main types of DGAT enzymes in the woody perennial biofuel plant Jatropha curcas, JcDGAT1 and JcDGAT2, were previously characterized only in heterologous systems. In this study, we investigated the functions of JcDGAT1 and JcDGAT2 in J. curcas.JcDGAT1 and JcDGAT2 were found to be predominantly expressed during the late stages of J. curcas seed development, in which large amounts of oil accumulated. As expected, overexpression of JcDGAT1 or JcDGAT2 under the control of the CaMV35S promoter gave rise to an increase in seed kernel oil production, reaching a content of 53.7% and 55.7% of the seed kernel dry weight, respectively, which were respectively 25% and 29.6% higher than that of control plants. The increase in seed oil content was accompanied by decreases in the contents of protein and soluble sugars in the seeds. Simultaneously, there was a two- to four-fold higher leaf TAG content in transgenic plants than in control plants. Moreover, by analysis of the fatty acid (FA) profiles, we found that JcDGAT1 and JcDGAT2 had the same substrate specificity with preferences for C18:2 in seed TAGs, and C16:0, C18:0, and C18:1 in leaf TAGs. Therefore, our study confirms the important role of JcDGAT1 and JcDGAT2 in regulating oil production in J. curcas.

Evaluation of oil accumulation and biodiesel property of Lindera glauca fruits among different germplasms and revelation of high oil producing mechanism for developing biodiesel

“…In support of this conclusion, transcript level of DGAT1 was on average fivefold higher than that of PDAT1 across all accessions (Fig. 5 b), and positively correlated with the amount of fruit oils (Table 1 ), revealing that DGAT1 may be a crucial regulator for oil synthesis in L. glauca fruits, coincided with metabolic and transcriptomic analyses of some oil plants [ 17 , 24 , 32 , 46 , 66 ], and also evidenced by the overexpression or mutant result of DGAT1 in several oil plants [ 67 – 74 ].…”

Macadamia germplasm and genomic database (MacadamiaGGD): A comprehensive platform for germplasm innovation and functional genomics in Macadamia

“…MacadamiaGGD integrates BLAST, enrichment analysis, and other tools for functional genomic research of Macadamia. Acyltransferases are the potential molecular targets for genetic engineering to increase the oil content and alter the fatty acid composition in the oil crops ( Zhang et al., 2021 ). Here, we provide a case study on the diacylglycerol acyltransferases ( DGAT s) of M. integrifolia by using the “BLAST”, “GO enrichment”, “JBrowse”, and “Gene Expression” function of MacadamiaGGD.…”

A review on the identification of transgenic oilseeds and oils

“…Oil is primarily composed of triglycerides (TAGs) accumulated in seeds during development, and some studies considered the TAG content as the total oil content (Zhao et al., 2021). In this way, technologies commonly used to determine TAG, such as gas chromatography (GC) and high‐performance liquid chromatography (HPLC), can also be applied to quantify the oil content in transgenic seeds (Cai et al., 2020; Mitchell et al., 2020; Zhang et al., 2021). The operation of oil content detection first facilitates the detection of a large number of samples.…”