Transcriptomic analysis of Perilla frutescens seed to insight into the biosynthesis and metabolic of unsaturated fatty acids

Abstract

BackgroundPerilla frutescens is well known for its high α-linolenic acid (ALA) accumulation in seeds and medicinal values as well as a source of edible and general-purpose oils. However, the regulatory mechanisms of the biosynthesis of fatty acid in its seeds remain poorly understood due to the lacking of sequenced genome. For better understanding the regulation of lipid metabolism and further increase its oil content or modify oil composition, time-course transcriptome and lipid composition analyses were performed.ResultsAnalysis of fatty acid content and composition showed that the α-linolenic acid and oleic acid accumulated rapidly from 5 DAF to 15 DAF and then kept relatively stable. However, the amount of palmitic acid and linoleic acid decreased quickly from 5 DAF to 15DAF. No significant variation of stearic acid content was observed from 5 DAF to 25DAF. Our transcriptome data analyses revealed that 110,176 unigenes were generated from six seed libraries at 5, 10, 20 DAF. Of these, 53 (31 up, 22 down) and 653 (259 up, 394 down) genes showed temporal and differentially expression during the seed development in 5 DAF vs 10 DAF, 20 vs 10 DAF, respectively. The differentially expressed genes were annotated and found to be involved in distinct functional categories and metabolic pathways. Deep mining of transcriptome data led to the identification of key genes involved in fatty acid and triacylglycerol biosynthesis and metabolism. Thirty seven members of transcription factor family AP2, B3 and NFYB putatively involved in oil synthesis and deposition were differentially expressed during seed development. The results of qRT-PCR for selected genes showed a strong positive correlation with the expression abundance measured in RNA-seq analysis.ConclusionsThe present study provides valuable genomic resources for characterizing Perilla seed gene expression at the transcriptional level and will extend our understanding of the complex molecular and cellular events of oil biosynthesis and accumulation in oilseed crops.Electronic supplementary materialThe online version of this article (10.1186/s12864-018-4595-z) contains supplementary material, which is available to authorized users.

Transcriptome Analysis of Jojoba (Simmondsia chinensis) during Seed Development and Liquid Wax Ester Biosynthesis

“…Three subunits, BC, CT-α, BCCP, were highly expressed during seed development with FPKM values of 195.99, 88.75, and 229.71, respectively, whereas the fourth subunit CT-β showed lower expression with an FPKM value of 4.95 (Table 2). A low expression level of CT-β was previously reported during the seed development of Perilla frutescens [27]. The expression of the same four subunits was reported in similar studies on Arbidopsis [40] and B. napus [41].…”

“…It has been employed to study gene expression during seed germination in Phelipanche aegyptiaca [19], floral initiation in Pongamia pinnata [20], seed development in pecan trees (Carya illinoinensis) [21], seed development in Camelina sativa [22], seed development in Euryale ferox [23], and seed development in Millettia pinnata [24]. Transcriptome analysis has also been employed to study oil biosynthesis in Pongamia pinnata [20], oil content and fatty acid composition in Camellia oleifera [25], lipid metabolism in pecan trees seeds (Carya illinoinensis) seeds (21), alpha-linolenic acid synthesis in tree peony seeds [26], triacylglycerol biosynthesis in Camelina sativa [22], oil accumulation in Millettia pinnata [24], and the biosynthesis of unsaturated fatty acids in Perilla frutescens [27].…”

Alpha-linolenic acid content and expression of KASII and FAD3 in perilla seed associated with altitude of cultivation areas

“…The transcription factor binding sites at 1.0 kb upstream of kasII and fad3 genes were found to be AP2 and B3 families, respectively. In particular, the AP2 and B3 transcription factors themselves play many roles in seed oil deposition, especially in the seed oil biosynthesis pathway 13 . Fig.…”

“…While the expression of fad3 has a seedspecific expression 12 . There were also reports showing that the expression of fad3 was higher in developing seeds than in leaves 9,13 . Indeed, at a certain time, gene expression would not be a sole indicator representing ALA production.…”

Characterization of the chloroplast genome of Perilla frutescens (Lamiaceae), an herb plant from China

“…Perilla frutescens is used in herbal medicine to treat a wide variety of ailments, as well as in cooking as a garnish and as a possible antidote to food poisoning, which has shown antioxidant, antiallergic, anti-inflammatory, antidepressant, anorexigenic, and tumor-preventing properties. However, there are limited clinical data to support the use of Perilla (Liao et al 2018). In this paper, the chloroplast genome of P. frutescens has been presented provides valuable genomic resources of the plant chloroplast genome, which will extend our information of TCM business in the world.…”