The genome sequence of Barbarea vulgaris facilitates the study of ecological biochemistry

Byrne, Stephen; Erthmann, Pernille Østerbye; Agerbirk, Niels; Bak, Søren; Hauser, Thure P.; Nagy, István; Paina, Cristiana; Asp, Torben

doi:10.1038/srep40728

Cited by 37 publications

(48 citation statements)

References 69 publications

(150 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Four oleanolic acid‐derived saponins from Barbarea vulgaris are known to be constitutively produced and induced upon flea beetle attack (Kuzina et al ., ; Toneatto et al ., ), and they have been shown to correlate with flea beetles resistance in two QTLs. The QTL on linkage group 1 controls expression of LUP5 , while the other QTL is known to contain a tandem array of eight CYP72A s (Shinoda et al ., ; Kuzina et al ., ; Byrne et al ., ). Here we demonstrate that only one of them, CYP72A552 , is responsible for oxidizing oleanolic acid to its corresponding alcohol, hederagenin, and that the monoglucoside of hederagenin is a major deterrent to the crucifer specialist herbivore diamondback moth and the solanaceous facultative ‘specialist’ tobacco hornworm.…”

Section: Discussionmentioning

confidence: 97%

“…Gene mining and cloning of CYP72A candidate genes from B. vulgaris Gene mining was performed on the available draft genome of B. vulgaris (Byrne et al, 2017): Barbarea vulgaris Genome Database, http://plen.ku.dk/Barbarea. Putative P450 candidates within the QTLs for flea beetles resistance were searched using the CLC Workbench (Qiagen).…”

Section: Methodsmentioning

confidence: 99%

“…The remaining two CYP72As in the QTL were placed in B. vulgaris contig 4433 and contig 1898. Nucleotide-based sequence alignment of the CYP72As showed that four of the BvCYP72A candidate genes (BvCYP72A552, BvCYP72A553, BvCYP72A562 and BvCYP72A563) shared high nucleotide sequence identity (from 87% to 93%) which may partially explain why two CYP72As (BvCYP72A553 and BvCYP72A563) were not assembled in the same position as the rest, as assembling algorithms do not facilitate assembly of such highly repetitive regions (Byrne et al, 2017;Fig. S1).…”

Section: Qtl Map and Genome-based Cloning Of Bvcyp72asmentioning

confidence: 99%

“…In the B. vulgaris genome, two quantitative trait loci (QTL) for the four known oleanolic acid‐based saponins were found to colocalise with a QTL for flea beetle resistance (Khakimov et al ., ; Byrne et al ., ). The first QTL also colocalises with LUP5, this finding is in agreement with the idea that β ‐amyrin‐derived saponins confer resistance to flea beetles, while LUP2, catalyzing lupeol‐based saponins, is not in the QTL.…”

Section: Introductionmentioning

confidence: 97%

“…The other type, the P-type (Pubescent), is susceptible to these insects (Agerbirk et al, 2003;Kuzina et al, 2011). Due to the interesting defense properties of Barbarea, including an unusual glucosinolate profile, it has become a model for evolution and ecology of plant defense compounds Byrne et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The cytochrome P450 CYP72A552 is key to production of hederagenin‐based saponins that mediate plant defense against herbivores

et al. 2019

Self Cite

View full text Add to dashboard Cite

Summary Plants continuously evolve new defense compounds. One class of such compounds is triterpenoid saponins. A few species in the Barbarea genus produce saponins as the only ones in the large crucifer family. However, the molecular mechanism behind saponin biosynthesis and their role in plant defense remains unclear. We used pathway reconstitution in planta, enzymatic production of saponins in vitro, insect feeding assays, and bioinformatics to identify a missing gene involved in saponin biosynthesis and saponin‐based herbivore defense. A tandem repeat of eight CYP72A cytochromes P450 colocalise with a quantitative trait locus (QTL) for saponin accumulation and flea beetle resistance in Barbarea vulgaris. We found that CYP72A552 oxidises oleanolic acid at position C‐23 to hederagenin. In vitro‐produced hederagenin monoglucosides reduced larval feeding by up to 90% and caused 75% larval mortality of the major crucifer pest diamondback moth and the tobacco hornworm. Sequence analysis indicated that CYP72A552 evolved through gene duplication and has been under strong selection pressure. In conclusion, CYP72A552 has evolved to catalyse the formation of hederagenin‐based saponins that mediate plant defense against herbivores. Our study highlights the evolution of chemical novelties by gene duplication and selection for enzyme innovations, and the importance of chemical modification in plant defense evolution.

show abstract

Section: Discussionmentioning

confidence: 97%

Section: Methodsmentioning

confidence: 99%

Section: Qtl Map and Genome-based Cloning Of Bvcyp72asmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The cytochrome P450 CYP72A552 is key to production of hederagenin‐based saponins that mediate plant defense against herbivores

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

The Role of the Glucosinolate-Myrosinase System in Mediating Greater Resistance of Barbarea verna than B. vulgaris to Mamestra brassicae Larvae

Müller

Schulz

Pagnotta³

et al. 2018

J Chem Ecol

View full text Add to dashboard Cite

We investigated the influences of two structurally similar glucosinolates, phenethylglucosinolate (gluconasturtiin, NAS) and its (S)-2-hydroxyl derivative glucobarbarin (BAR), as well as their hydrolysis products on larvae of the generalist Mamestra brassicae (Lepidoptera: Noctuidae). Previous results suggested a higher defensive activity of BAR than NAS based on resistance toward M. brassicae larvae of natural plant genotypes of Barbarea vulgaris R. Br. (Brassicaceae) dominated by BAR. In the present study, the hypothesis of a higher defensive activity of BAR than NAS was tested by comparing two Barbarea species similarly dominated either by BAR or by NAS and by testing effects of isolated BAR and NAS on larval survival and feeding preferences. Larvae reared on leaf disks of B. verna (Mill.) Asch. had a lower survival than those reared on B. vulgaris P- and G-chemotypes. Leaves of B. verna were dominated by NAS, whereas B. vulgaris chemotypes were dominated by BAR or its epimer. In addition, B. verna leaves showed a threefold higher activity of the glucosinolate-activating myrosinase enzymes. The main product of NAS from breakdown by endogenous enzymes including myrosinases ("autolysis") in B. verna leaves was phenethyl isothiocyanate, while the main products of BAR in autolyzed B. vulgaris leaves were a cyclized isothiocyanate product, namely an oxazolidine-2-thione, and a downstream metabolite, an oxazolidin-2-one. The glucosinolates BAR and NAS were isolated and offered to larvae on disks of cabbage. Both glucosinolates exerted similar negative effects on larval survival but effects of NAS tended to be more detrimental. Low concentrations of BAR, but not of NAS, stimulated larval feeding, whereas high BAR concentrations acted deterrent. NAS only tended to be deterrent at the highest concentration, but the difference was not significant. Recoveries of NAS and BAR on cabbage leaf disks were similar, and when hydrolyzed by mechanical leaf damage, the same isothiocyanate-type products as in Barbarea plants were formed with further conversion of BAR to cyclic products, (R)-5-phenyloxazolidine-2-thione [(R)-barbarin] and (R)-5-phenyloxazolidin-2-one [(R)-resedine]. We conclude that a previously proposed generally higher defensive activity of BAR than NAS to M. brassicae larvae could not be confirmed. Indeed, the higher resistance of NAS-containing B. verna plants may be due to a combined effect of rather high concentrations of NAS and a relatively high myrosinase activity or other plant traits not investigated yet.

show abstract

A tandem array of UDP-glycosyltransferases from the UGT73C subfamily glycosylate sapogenins, forming a spectrum of mono- and bisdesmosidic saponins

2018

View full text Add to dashboard Cite

This study identifies six UGT73Cs all able to glucosylate sapogenins at positions 3 and/or 28 which demonstrates that B. vulgaris has a much richer arsenal of UGTs involved in saponin biosynthesis than initially anticipated. The wild cruciferous plant Barbarea vulgaris is resistant to some insects due to accumulation of two monodesmosidic triterpenoid saponins, oleanolic acid 3-O-β-cellobioside and hederagenin 3-O-β-cellobioside. Insect resistance depends on the structure of the sapogenin aglycone and the glycosylation pattern. The B. vulgaris saponin profile is complex with at least 49 saponin-like metabolites, derived from eight sapogenins and including up to five monosaccharide units. Two B. vulgaris UDP-glycosyltransferases, UGT73C11 and UGT73C13, O-glucosylate sapogenins at positions 3 and 28, forming mainly 3-O-β-D-glucosides. The aim of this study was to identify UGTs responsible for the diverse saponin oligoglycoside moieties observed in B. vulgaris. Twenty UGT genes from the insect resistant genotype were selected and heterologously expressed in Nicotiana benthamiana and/or Escherichia coli. The extracts were screened for their ability to glycosylate sapogenins (oleanolic acid, hederagenin), the hormone 24-epibrassinolide and sapogenin monoglucosides (hederagenin and oleanolic acid 3-O-β-D-glucosides). Six UGTs from the UGT73C subfamily were able to glucosylate both sapogenins and both monoglucosides at positions 3 and/or 28. Some UGTs formed bisdesmosidic saponins efficiently. At least four UGT73C genes were localized in a tandem array with UGT73C11 and possibly UGT73C13. This organization most likely reflects duplication events followed by sub- and neofunctionalization. Indeed, signs of positive selection on several amino acid sites were identified and modelled to be localized on the UGT protein surface. This tandem array is proposed to initiate higher order bisdesmosidic glycosylation of B. vulgaris saponins, leading to the recently discovered saponin structural diversity, however, not directly to known cellobiosidic saponins.

show abstract

The genome sequence of Barbarea vulgaris facilitates the study of ecological biochemistry

Cited by 37 publications

References 69 publications

The cytochrome P450 CYP72A552 is key to production of hederagenin‐based saponins that mediate plant defense against herbivores

The cytochrome P450 CYP72A552 is key to production of hederagenin‐based saponins that mediate plant defense against herbivores

The Role of the Glucosinolate-Myrosinase System in Mediating Greater Resistance of Barbarea verna than B. vulgaris to Mamestra brassicae Larvae

A tandem array of UDP-glycosyltransferases from the UGT73C subfamily glycosylate sapogenins, forming a spectrum of mono- and bisdesmosidic saponins

Contact Info

Product

Resources

About