A new allele of flower color gene W1 encoding flavonoid 3'5'-hydroxylase is responsible for light purple flowers in wild soybean Glycine soja

<p>Abstract</p> <p>Background</p> <p><it>Glycine soja </it>is a wild relative of soybean that has purple flowers. No flower color variant of <it>Glycine soja </it>has been found in the natural habitat.</p> <p>Results</p> <p>B09121, an accession with light purple flowers, was discovered in southern Japan. Genetic analysis revealed that the gene responsible for the light purple flowers was allelic to the <it>W1 </it>locus encoding flavonoid 3'5'-hydroxylase (F3'5'H). The new allele was designated as <it>w1-lp</it>. The dominance relationship of the locus was <it>W1 </it>><it>w1-lp </it>><it>w1</it>. One F₂plant and four F₃plants with purple flowers were generated in the cross between B09121 and a Clark near-isogenic line with <it>w1 </it>allele. Flower petals of B09121 contained lower amounts of four major anthocyanins (malvidin 3,5-di-<it>O</it>-glucoside, petunidin 3,5-di-<it>O</it>-glucoside, delphinidin 3,5-di-<it>O</it>-glucoside and delphinidin 3-<it>O</it>-glucoside) common in purple flowers and contained small amounts of the 5'-unsubstituted versions of the above anthocyanins, peonidin 3,5-di-<it>O</it>-glucoside, cyanidin 3,5-di-<it>O</it>-glucoside and cyanidin 3-<it>O</it>-glucoside, suggesting that F3'5'H activity was reduced and flavonoid 3'-hydroxylase activity was increased. F3'5'H cDNAs were cloned from Clark and B09121 by RT-PCR. The cDNA of B09121 had a unique base substitution resulting in the substitution of valine with methionine at amino acid position 210. The base substitution was ascertained by dCAPS analysis. The polymorphism associated with the dCAPS markers co-segregated with flower color in the F₂population. F₃progeny test, and dCAPS and indel analyses suggested that the plants with purple flowers might be due to intragenic recombination and that the 65 bp insertion responsible for gene dysfunction might have been eliminated in such plants.</p> <p>Conclusions</p> <p>B09121 may be the first example of a flower color variant found in nature. The light purple flower was controlled by a new allele of the <it>W1 </it>locus encoding F3'5'H. The flower petals contained unique anthocyanins not found in soybean and <it>G. soja</it>. B09121 may be a useful tool for studies of the structural and functional properties of F3'5'H genes as well as investigations on the role of flower color in relation to adaptation of <it>G. soja </it>to natural habitats.</p

Allelic variation of soybean flower color gene W4 encoding dihydroflavonol 4-reductase 2

BACKGROUND: Flower color of soybean is primarily controlled by six genes, viz., W1, W2, W3, W4, Wm and Wp. This study was conducted to investigate the genetic and chemical basis of newly-identified flower color variants including two soybean mutant lines, 222-A-3 (near white flower) and E30-D-1 (light purple flower), a near-isogenic line (Clark-w4), flower color variants (T321 and T369) descended from the w4-mutable line and kw4 (near white flower, Glycine soja). RESULTS: Complementation tests revealed that the flower color of 222-A-3 and kw4 was controlled by the recessive allele (w4) of the W4 locus encoding dihydroflavonol 4-reductase 2 (DFR2). In 222-A-3, a single base was deleted in the first exon resulting in a truncated polypeptide consisting of 24 amino acids. In Clark-w4, base substitution of the first nucleotide of the fourth intron abolished the 5′ splice site, resulting in the retention of the intron. The DFR2 gene of kw4 was not expressed. The above results suggest that complete loss-of-function of DFR2 gene leads to near white flowers. Light purple flower of E30-D-1 was controlled by a new allele at the W4 locus, w4-lp. The gene symbol was approved by the Soybean Genetics Committee. In E30-D-1, a single-base substitution changed an amino acid at position 39 from arginine to histidine. Pale flowers of T369 had higher expression levels of the DFR2 gene. These flower petals contained unique dihydroflavonols that have not yet been reported to occur in soybean and G. soja. CONCLUSIONS: Complete loss-of-function of DFR2 gene leads to near white flowers. A new allele of the W4 locus, w4-lp regulates light purple flowers. Single amino acid substitution was associated with light purple flowers. Flower petals of T369 had higher levels of DFR2 gene expression and contained unique dihydroflavonols that are absent in soybean and G. soja. Thus, mutants of the DFR2 gene have unique flavonoid compositions and display a wide variety of flower color patterns in soybean, from near white, light purple, dilute purple to pale

New flavonoid chemotypes from Asplenium normale (Aspleniaceae) in Malaysia

Seven Asplenium normale individuals in Malaysia were surveyed for flavonoid com¬pounds. They were divided into two chemotypes, H- and I-types. The flavonoids were isolated by various chromatography and identified by TLC, HPLC, UV spectroscopic, LC-MS and NMR sur¬veys. Two flavone O-glycosides, apigenin 7-O-rhamnosyl-(1→4)-rhamnoside (1) and apigenin 7- O-rhamnosyl-(1→4)-rhamnoside-4'-O-rhamnoside (2), and two flavone C-glycosides, vicenin-2 (6) and lucenin-2 (7), were contained in one chemotype (H-type). On the other hand, two flavonol O-glycosides, kaempferol 3-O-glucosylrhamnoside (3) and kaempferol 3,4'-di-O-glycoside (4) and a flavone O-glycoside, genkwanin 4'-O-glucosyl-(1→3)-rhamnoside (5), were found from another chemotype (I-type) together with 6 and 7. In cases of Japanese Asplenium normale and related species, seven chemotypes have been reported. However, their chemotypes did not include flavonol O-glycosides and apigenin trirhamnoside. Apigenin 7-O-rhamnosyl-(1→4)-rhamnoside (1) and apigenin 7-O-rhamnosyl-(1→4)-rhamnoside-4'-O-rhamnoside (2) were reported in nature for the first time

Growth performance, in vitro antioxidant properties and chemical composition of the halophyte Limonium algarvense Erben are strongly influenced by the irrigation salinity

Limonium algarvense Erben (sea lavender) is a halophyte species with potential to provide natural ingredients with in vitro antioxidant, anti-inflammatory, neuroprotective and antidiabetic properties. This study reports for the first time the 1) cultivation of sea lavender in greenhouse conditions under irrigation with freshwater (approx. 0 mM NaCl) and saline aquaculture wastewater (300 and 600 mM NaCl), and 2) the influence of the irrigation salinity on the plant performance (e.g growth, number of produced leaves and flowers), in vitro antioxidant properties [radical scavenging activity (DPPH and ABTS), ferric reducing antioxidant power (FRAP), metal chelating properties on copper (CCA) and iron (ICA)], toxicity (in vitro on three mammalian cell lines) and chemical composition (determined by LC-ESI-HRMS/MS). The freshwater-irrigated plants had better growth performance than those irrigated with saltwater. Extracts from wild plants, had the highest antioxidant activity, but those from cultivated ones kept high in vitro antioxidant properties and interesting chemical profile. The flowers' extracts of plants irrigated with 300 mM NaCl had the highest antioxidant activities against DPPH, whereas those from freshwater-irrigated plants were more active on ABTS, CCA and FRAP. Most of the extracts showed nil toxicity. The flowers' extracts displayed the highest diversity of compounds, mainly quercetin, apigenin, luteolin, naringenin and their glycoside derivatives. Moreover, their abundance varied with the irrigation salinity. These data indicate that sea lavender plants can be successfully cultivated in greenhouse conditions under fresh- and saltwater irrigation, maintaining interesting biological and chemical properties.Funding Agency Portuguese Foundation for Science and Technology Portuguese National Budget CCMAR/Multi/04326/2019 GreenVet project ALG-01-0145-FEDER-028876 XtrerneAquaCrops FA-05-2017-028 Lisboa-01-0145-FEDER-022125-RNEM-IST ID/QUI/00100/201 Portuguese Foundation for Science and Technology SFRH/BD/116604/2016 CEECIND/00425/2017info:eu-repo/semantics/publishedVersio

Phenols in Leaves and Bark of Fagus sylvatica as Determinants of Insect Occurrences

Beech forests play an important role in temperate and north Mediterranean ecosystems in Greece since they occupy infertile montane soils. In the last glacial maximum, Fagus sylvatica (beech) was confined to Southern Europe where it was dominant and in the last thousand years has expanded its range to dominate central Europe. We sampled four different beech forest types. We found 298 insect species associated with beech trees and dead beech wood. While F. sylvatica and Quercus (oak) are confamilial, there are great differences in richness of the associated entomofauna. Insect species that inhabit beech forests are less than one fifth of those species living in oak dominated forests despite the fact that beech is the most abundant central and north European tree. There is a distinct paucity of monophagous species on beech trees and most insect species are shared between co-occurring deciduous tree species and beech. This lack of species is attributed to the vegetation history and secondary plant chemistry. Bark and leaf biophenols from beech indicate that differences in plant secondary metabolites may be responsible for the differences in the richness of entomofauna in communities dominated by beech and other deciduous trees

The First Illumina-Based De Novo Transcriptome Sequencing and Analysis of Safflower Flowers

BACKGROUND: The safflower, Carthamus tinctorius L., is a worldwide oil crop, and its flowers, which have a high flavonoid content, are an important medicinal resource against cardiovascular disease in traditional medicine. Because the safflower has a large and complex genome, the development of its genomic resources has been delayed. Second-generation Illumina sequencing is now an efficient route for generating an enormous volume of sequences that can represent a large number of genes and their expression levels. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the genes and pathways that might control flavonoids and other secondary metabolites in the safflower, we used Illumina sequencing to perform a de novo assembly of the safflower tubular flower tissue transcriptome. We obtained a total of 4.69 Gb in clean nucleotides comprising 52,119,104 clean sequencing reads, 195,320 contigs, and 120,778 unigenes. Based on similarity searches with known proteins, we annotated 70,342 of the unigenes (about 58% of the identified unigenes) with cut-off E-values of 10(-5). In total, 21,943 of the safflower unigenes were found to have COG classifications, and BLAST2GO assigned 26,332 of the unigenes to 1,754 GO term annotations. In addition, we assigned 30,203 of the unigenes to 121 KEGG pathways. When we focused on genes identified as contributing to flavonoid biosynthesis and the biosynthesis of unsaturated fatty acids, which are important pathways that control flower and seed quality, respectively, we found that these genes were fairly well conserved in the safflower genome compared to those of other plants. CONCLUSIONS/SIGNIFICANCE: Our study provides abundant genomic data for Carthamus tinctorius L. and offers comprehensive sequence resources for studying the safflower. We believe that these transcriptome datasets will serve as an important public information platform to accelerate studies of the safflower genome, and may help us define the mechanisms of flower tissue-specific and secondary metabolism in this non-model plant

A systems approach to identifying correlated gene targets for the loss of colour pigmentation in plants

<p>Abstract</p> <p>Background</p> <p>The numerous diverse metabolic pathways by which plant compounds can be produced make it difficult to predict how colour pigmentation is lost for different tissues and plants. This study employs mathematical and <it>in silico </it>methods to identify correlated gene targets for the loss of colour pigmentation in plants from a whole cell perspective based on the full metabolic network of <it>Arabidopsis</it>. This involves extracting a self-contained flavonoid subnetwork from the AraCyc database and calculating feasible metabolic routes or elementary modes (EMs) for it. Those EMs leading to anthocyanin compounds are taken to constitute the anthocyanin biosynthetic pathway (ABP) and their interplay with the rest of the EMs is used to study the minimal cut sets (MCSs), which are different combinations of reactions to block for eliminating colour pigmentation. By relating the reactions to their corresponding genes, the MCSs are used to explore the phenotypic roles of the ABP genes, their relevance to the ABP and the impact their eliminations would have on other processes in the cell.</p> <p>Results</p> <p>Simulation and prediction results of the effect of different MCSs for eliminating colour pigmentation correspond with existing experimental observations. Two examples are: i) two MCSs which require the simultaneous suppression of genes DFR and ANS to eliminate colour pigmentation, correspond to observational results of the same genes being co-regulated for eliminating floral pigmentation in <it>Aquilegia </it>and; ii) the impact of another MCS requiring CHS suppression, corresponds to findings where the suppression of the early gene CHS eliminated nearly all flavonoids but did not affect the production of volatile benzenoids responsible for floral scent.</p> <p>Conclusions</p> <p>From the various MCSs identified for eliminating colour pigmentation, several correlate to existing experimental observations, indicating that different MCSs are suitable for different plants, different cells, and different conditions and could also be related to regulatory genes. Being able to correlate the predictions with experimental results gives credence to the use of these mathematical and <it>in silico </it>analyses methods in the design of experiments. The methods could be used to prioritize target enzymes for different objectives to achieve desired outcomes, especially for less understood pathways.</p