The Eruca sativa Genome and Transcriptome: A Targeted Analysis of Sulfur Metabolism and Glucosinolate Biosynthesis Pre and Postharvest

AbstractRocket (Eruca sativa) is a source of health-related metabolites called glucosinolates (GSLs) and isothiocyanates (ITCs) but little is known of the genetic and transcriptomic mechanisms responsible for regulating pre and postharvest accumulations. We present the first de novo reference genome assembly and annotation, with ontogenic and postharvest transcriptome data relating to sulfur assimilation, transport, and utilization. Diverse gene expression patterns related to sulfur metabolism and GSL biosynthesis are present between inbred lines of rocket. A clear pattern of differential expression determines GSL abundance and the formation of hydrolysis products. One breeding line sustained GSL accumulation and hydrolysis product formation throughout storage. Copies of MYB28, SLIM1, SDI1 and ESM1 orthologs have increased and differential expression postharvest, and are associated with GSLs and hydrolysis product formation. Two glucosinolate transporter gene orthologs (GTR2) were found to be associated with increased GSL accumulations.

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Tumorous Stem Development of Brassica Juncea: A Complex Regulatory Network of Stem Formation and Identification of Key Genes in Glucosinolate Biosynthesis

Plants ◽

10.3390/plants9081006 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1006

Author(s):

Mengyao Li ◽

Fangjie Xie ◽

Jie Li ◽

Bo Sun ◽

Ya Luo ◽

...

Keyword(s):

Brassica Juncea ◽

Sulfur Metabolism ◽

Genetic Research ◽

Glucosinolate Biosynthesis ◽

Complex Biological Process ◽

Significant Downward Trend ◽

Aliphatic Glucosinolates ◽

Stem Development ◽

Brassica Vegetable ◽

Main Component

Stem mustard is a stem variety of mustard, an important Brassica vegetable. The formation and development of the tumorous stem, which is the key organ for the direct yield and quality, is a complex biological process involving morphogenesis, material accumulation and gene regulation. In this study, we demonstrated through anatomical studies that stem swelling is mainly dependent on the increase in the number of cells and the volume of parenchyma cells in the cortex and pith. To further understand transcript and metabolic changes during stem swelling, we obtained 27,901 differentially expressed genes, of which 671 were specifically detected using transcriptome sequencing technology in all four stages of stem swelling. Functional annotation identified enrichment for genes involved in photosynthesis, energy metabolism, cell growth, sulfur metabolism and glucosinolate biosynthesis. Glucosinolates are a group of nitrogen- and sulfur-containing secondary metabolites, which largely exist in the Cruciferous vegetables. HPLC analysis of the contents and components of glucosinolates in four different stem development stages revealed eight glucosinolates, namely, three aliphatic glucosinolates (sinigrin, glucoalyssin and gluconapin), four indole glucosinolates (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin and neoglucobrassicin) and one aromatic glucosinolate (gluconasturtiin). All these types of glucosinolates showed a significant downward trend during the stem swelling period. The content of aliphatic glucosinolates was the highest, with sinigrin being the main component. In addition, qPCR was used to validate the expression of nine genes involved in glucosinolate biosynthesis. Most of these genes were down-regulated during stem swelling in qPCR, which is consistent with transcriptome data. These data provide a basic resource for further molecular and genetic research on Brassica juncea.

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Glucosinolate biosynthesis in Eruca sativa

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2016.10.024 ◽

2016 ◽

Vol 109 ◽

pp. 452-466 ◽

Cited By ~ 8

Author(s):

Dimitra Katsarou ◽

Michalis Omirou ◽

Kalliopi Liadaki ◽

Daniela Tsikou ◽

Costas Delis ◽

...

Keyword(s):

Eruca Sativa ◽

Glucosinolate Biosynthesis

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Glucosinolate biosynthesis: demonstration and characterization of the condensing enzyme of the chain elongation cycle in Eruca sativa

Phytochemistry ◽

10.1016/j.phytochem.2004.02.021 ◽

2004 ◽

Vol 65 (8) ◽

pp. 1073-1084 ◽

Cited By ~ 25

Author(s):

K Falk

Keyword(s):

Chain Elongation ◽

Eruca Sativa ◽

Glucosinolate Biosynthesis ◽

Elongation Cycle ◽

Condensing Enzyme

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Selenium Biofortification Differentially Affects Sulfur Metabolism and Accumulation of Phytochemicals in Two Rocket Species (Eruca Sativa Mill. and Diplotaxis Tenuifolia) Grown in Hydroponics

Plants ◽

10.3390/plants8030068 ◽

2019 ◽

Vol 8 (3) ◽

pp. 68 ◽

Cited By ~ 10

Author(s):

Stefano Dall’Acqua ◽

Andrea Ertani ◽

Elizabeth Pilon-Smits ◽

Marta Fabrega-Prats ◽

Michela Schiavon

Keyword(s):

Amino Acid ◽

Acid Content ◽

Sulfur Metabolism ◽

Plant Defence ◽

Amino Acid Content ◽

Dry Weight ◽

Selenium Supplementation ◽

Eruca Sativa ◽

Fresh Leaf ◽

Wild Rocket

Biofortification can be exploited to enrich plants in selenium (Se), an essential micronutrient for humans. Selenium as selenate was supplied to two rocket species, Eruca sativa Mill. (salad rocket) and Diplotaxis tenuifolia (wild rocket), at 0–40 μM in hydroponics and its effects on the content and profile of sulphur (S)-compounds and other phytochemicals was evaluated. D. tenuifolia accumulated more total Se and selenocysteine than E. sativa, concentrating up to ~300 mg Se kg−1 dry weight from 10–40 μM Se. To ensure a safe and adequate Se intake, 30 and 4 g fresh leaf material from E. sativa grown with 5 and 10–20 μM Se, respectively or 4 g from D. tenuifolia supplied with 5 μM Se was estimated to be optimal for consumption. Selenium supplementation at or above 10 μM differentially affected S metabolism in the two species in terms of the transcription of genes involved in S assimilation and S-compound accumulation. Also, amino acid content decreased with Se in E. sativa but increased in D. tenuifolia and the amount of phenolics was more reduced in D. tenuifolia. In conclusion, selenate application in hydroponics allowed Se enrichment of rocket. Furthermore, Se at low concentration (5 μM) did not significantly affect accumulation of phytochemicals and plant defence S-metabolites.

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Regulation of glucosinolate biosynthesis

Journal of Experimental Botany ◽

10.1093/jxb/eraa479 ◽

2020 ◽

Author(s):

Simon Mitreiter ◽

Tamara Gigolashvili

Keyword(s):

Transcription Factors ◽

Molecular Mechanisms ◽

Plant Hormone ◽

Sulfur Metabolism ◽

Crop Species ◽

Environmental Signals ◽

Glucosinolate Biosynthesis ◽

The Past ◽

Helix Loop Helix ◽

Open Questions

Abstract Glucosinolates are secondary defense metabolites produced by plants of the order Brassicales, which includes the model species Arabidopsis and many crop species. In the past 13 years, the regulation of glucosinolate synthesis in plants has been intensively studied, with recent research revealing complex molecular mechanisms that connect glucosinolate production with responses to other central pathways. In this review, we discuss how the regulation of glucosinolate biosynthesis is ecologically relevant for plants, how it is controlled by transcription factors, and how this transcriptional machinery interacts with hormonal, environmental, and epigenetic mechanisms. We present the central players in glucosinolate regulation, MYB and basic helix–loop–helix transcription factors, as well as the plant hormone jasmonate, which together with other hormones and environmental signals allow the coordinated and rapid regulation of glucosinolate genes. Furthermore, we highlight the regulatory connections between glucosinolates, auxin, and sulfur metabolism and discuss emerging insights and open questions on the regulation of glucosinolate biosynthesis.

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