Seed-specific overexpression of Arabidopsis DGAT1 in Indian mustard (Brassica juncea) increases seed oil content and seed weight

Abstract

Oil content is an important yield trait in Brassica juncea (L.) Coss. Improvements to yield levels of mustard by conventional breeding methods have reached a plateau. The application of transgenic technology is an area that has not yet been explored for improving the oil content of B. juncea. In this study, the effect of overexpression of AtDGAT1 (a key gene involved in oil biosynthesis) on the seed oil content of B. juncea was investigated. For seed-specific overexpression, the gene was linked to Arabidopsis thaliana oleosin promoter and mobilized into mustard through Agrobacterium-mediated transformation. Transformants were selected on MS medium containing 50 mg/L kanamycin, and a transformation frequency of 10.5% was obtained. A total of 10 transgenic events were generated. Analyses of seed weight, oil content, and other yield traits in T1 transgenics showed that seed-specific overexpression of AtDGAT1 significantly improved the oil content and seed weight. The maximum oil content increase observed in the transgenic seeds was 8.3% compared with the wild-type plants. Total fatty acid content was increased from 4% to 14% in six of the seven events. However, the content of oleic and linoleic acid was reduced and, of these two, oleic acid content showed drastic reduction.

Identification of microRNAs involved in lipid biosynthesis and seed size in developing sea buckthorn seeds using high-throughput sequencing

“…It is well known that the DGAT enzyme catalyzes a rate-limiting reaction in TAG bioassembly, and DGAT1 and DGAT2 genes are responsible for the progress of this reaction 54 . Seed-specific overexpression of AtDGAT1 increased the seed oil content by up to 8.3% in transgenic Brassica juncea as compared to wild type plants 55 . The expression patterns of both XsDGAT1 and XsDGAT2 correlated with oil accumulation in developing Xanthoceras sorbifolia embryos, and overexpression of these genes increased total seed oil content in transgenic plants as compared to wild-type plants 54 .…”

Properties and Biotechnological Applications of Acyl‐CoA:diacylglycerol Acyltransferase and Phospholipid:diacylglycerol Acyltransferase from Terrestrial Plants and Microalgae

“…The overexpression of T. majus DGAT1 in Arabidopsis, high‐erucic‐acid rapeseed, and canola‐type B. napus also led to enhanced seed oil content (Xu et al, ). Following these aforementioned studies, many groups have further used DGAT1 from different species to boost seed content in various crops such as G. max (Hatanaka et al, ; Roesler et al, ), B. juncea (Savadi et al, ), Z. mays (Alameldin et al, ), C. sativa (Kim et al, ), and Jatropa curcas (Maravi et al, ). Moreover, overexpression of DGAT1 from microalgae, such as Chlorella ellipsoidea and Nannochloropsis oceanica , also led to increased oil content in Arabidopsis and B. napus (Guo et al, ; Zienkiewicz et al, ).…”

RNA-seq data reveals a coordinated regulation mechanism of multigenes involved in the high accumulation of palmitoleic acid and oil in sea buckthorn berry pulp

“…Overexpression of DGAT cDNA in wild-type Arabidopsis seeds increased the oil content by 11–28% [64]. In addition, seed-specific overexpression of AtDGAT1 in Brassica juncea seed improved the oil content significantly, with a maximum oil content increase of 8.3% in the transgenic plants compared to that in the wild-type plants [65]. In addition, we examined the expression profiles of the GPD1 and DGAT1 genes in seeds and berry pulp tissues of one sea buckthorn line, ‘XE3’, and found that these two genes had higher expression in pulp (with an oil content of 36.90%) than in seeds (14.15%) [66].…”