Highbush blueberry (Vaccinium corymbosum) fruits contain substantial quantities of flavonoids, which are implicated in a wide range of health benefits. Although the flavonoid constituents of ripe ...blueberries are known, the molecular genetics underlying their biosynthesis, localization, and changes that occur during development have not been investigated. Two expressed sequence tag libraries from ripening blueberry fruit were constructed as a resource for gene identification and quantitative realtime reverse transcription-polymerase chain reaction primer design. Gene expression profiling by quantitative real-time reverse transcription-polymerase chain reaction showed that flavonoid biosynthetic transcript abundance followed a tightly regulated biphasic pattern, and transcript profiles were consistent with the abundance of the three major classes of flavonoids.Proanthocyanidins (PAs) and corresponding biosynthetic transcripts encoding anthocyanidin reducíase and leucoanthocyanidin reducíase were most concentrated in young fruit and localized predominantly to the inner fruit tissue containing the seeds and placentae. Mean PA polymer length was seven to 8.5 subunits, linked predominantly via B-type linkages, and was relatively constant throughout development. Flavonol accumulation and localization patterns were similar to those of the PAs, and the B-ring hydroxylation pattern of both was correlated with flavonoid-3'-hydroxylase transcript abundance. By contrast, anthocyanins accumulated late in maturation, which coincided with a peak in flavonoid-3-O-glycosyltransferase and flavonoid-3' 5'-hydroxylase transcripts. Transcripts of VcMYBPAl, which likely encodes an R2R3-MYB transcriptional regulator of PA synthesis, were prominent in both phases of development. Furthermore, the initiation of ripening was accompanied by a substantial rise in abscisic acid, a growth regulator that may be an important component of the ripening process and contribute to the regulation of blueberry flavonoid biosynthesis.
Fusarium head blight (FHB or scab) caused by Fusarium spp. is a destructive disease of wheat. Since the most effective sources of FHB resistance are typically associated with unfavorable agronomic ...traits, breeding commercial cultivars that combine desired agronomic traits and a high level of FHB resistance remains a considerable challenge. A better understanding of the molecular mechanisms governing FHB resistance will help to design more efficient and precise breeding strategies. Here, multiple molecular tools and assays were deployed to compare the resistant variety Sumai3 with three regionally adapted Canadian cultivars. Macroscopic and microscopic disease evaluation established the relative level of Type II FHB resistance of the four varieties and revealed that the F. graminearum infection process displayed substantial temporal differences among organs. The rachis was found to play a critical role in preventing F. graminearum spread within spikes. Large-scale, organ-specific RNA-seq at different times after F. graminearum infection demonstrated that diverse defense mechanisms were expressed faster and more intensely in the spikelet of resistant varieties. The roles of plant hormones during the interaction of wheat with F. graminearum was inferred based on the transcriptomic data obtained and the quantification of the major plant hormones. Salicylic acid and jasmonic acid were found to play predominantly positive roles in FHB resistance, whereas auxin and ABA were associated with susceptibility, and ethylene appeared to play a dual role during the interaction with F graminearum.
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•Wide diversity of profiles of bioactive compounds present in pea accessions.•An improved method for simultaneous detection of multiple phytoestrogens.•Developed method for direct ...analysis of isoflavones in their natural forms.•Isoliquiritigenin is the predominant phytoestrogen in the analyzed accessions.•Providing an immense resource for pea research community and breeding.
Pea (Pisum sativum L.) is an important legume crop providing a good source of protein, vitamins, minerals and bioactive compounds with health benefits for humans. In this study, an improved method for simultaneous analysis of multiple phytoestrogens among 100 pea accessions was developed. Ipriflavone, (a synthetic isoflavone), was used as an internal standard for the semiquantitative analysis of 17 phytoestrogens including isoflavone aglycones and conjugates, allowing direct analysis of isoflavones in their naturally occurring forms. This comprehensive dataset demonstrated that the isoflavones varied greatly and some accessions tended to have high levels of multiple phytoestrogens among the 100 accessions analyzed. Isoliquiritigenin followed by glycitein were the predominant compounds detected in the accessions and showed the highest correlation with the total phytoestrogens content. Secoisolariciresinol content was consistently higher in yellow cotyledon peas than in green cotyledon peas, whereas the contents of coumestrol, genestein and secoisolariciresinol were significantly correlated with seed coat color. The total phenolics and saponins showed a wide range of variability among the accessions with higher concentrations of total phenolics observed in seeds with pigmented seed coat or yellow cotyledon seeds, suggesting the synthesis of saponins and phenolics are significantly affected by metabolic pathway genes controlling cotyledon color or seed coat color. This study profiled the variability of bioactive compounds of pea seed quality traits in diverse pea accessions and provides an immense resource for continued research, breeding and selection of genotypes for a wide range of applications.
Saponin Biosynthesis in Pulses Yu, Bianyun; Patterson, Nii; Zaharia, L Irina
Plants,
12/2022, Letnik:
11, Številka:
24
Journal Article
Recenzirano
Odprti dostop
Pulses are a group of leguminous crops that are harvested solely for their dry seeds. As the demand for plant-based proteins grows, pulses are becoming important food crops worldwide. In addition to ...being a rich source of nutrients, pulses also contain saponins that are traditionally considered anti-nutrients, and impart bitterness and astringency. Saponins are plant secondary metabolites with great structural and functional diversity. Given their diverse functional properties and biological activities, both undesirable and beneficial, saponins have received growing attention. It can be expected that redirecting metabolic fluxes to control the saponin levels and produce desired saponins would be an effective approach to improve the nutritional and sensory quality of the pulses. However, little effort has been made toward understanding saponin biosynthesis in pulses, and, thus there exist sizable knowledge gaps regarding its pathway and regulatory network. In this paper, we summarize the research progress made on saponin biosynthesis in pulses. Additionally, phylogenetic relationships of putative biosynthetic enzymes among multiple pulse species provide a glimpse of the evolutionary routes and functional diversification of saponin biosynthetic enzymes. The review will help us to advance our understanding of saponin biosynthesis and aid in the development of molecular and biotechnological tools for the systematic optimization of metabolic fluxes, in order to produce the desired saponins in pulses.
Background and Objectives
Fermentation has been increasingly used as a “clean” processing technique to modify proteins. The goal of this research was to assess the use of solid‐state fermentation ...(SSF) by Aspergillus oryzae on pea (pea protein isolate PPI) and navy bean protein isolates (NBPI) for different time periods (0–48 or 0−72 h, respectively) and its impact on their nutrition and volatile profile.
Findings
The SSF process resulted in higher total phenolic content and lower protein digestibility, and consequently, the protein quality was reduced for both pulses. The quantity of the volatile compounds initially present in the samples did not change substantially after SSF; however, many new compounds were identified in fermented PPI, which have been reported to have pleasant sensory properties.
Conclusions
The protein quality of PPI or NBPI was not improved by A. oryzae SSF; however, the results suggest the potential for using SSF to positively modify the volatile profile of PPI.
Significance and Novelty
The findings of this research strengthened our knowledge base of fermented pulse ingredients with the use of protein isolates and navy beans, narrowing the somewhat limited gap for fermentation application to high protein substrates.
Abstract
FLOWERING LOCUS T
(
FT
) can promote early flowering in annual species, but such role has not been well demonstrated in woody species. We produced self and reciprocal grafts involving ...non-transgenic blueberry (NT) and transgenic blueberry (T) carrying a 35S-driven blueberry
FT
(
VcFT
-OX). We demonstrated that the transgenic
VcFT
-OX rootstock promoted flowering of non-transgenic blueberry scions in the NT (scion):T (rootstock) grafts. We further analyzed RNA-Seq profiles and six groups of phytohormones in both NT:T and NT:NT plants. We observed content changes of several hormone metabolites, in a descending order, in the transgenic NT:T, non-transgenic NT:T, and non-transgenic NT:NT leaves. By comparing differential expression transcripts (DETs) of these tissues in relative to their control, we found that the non-transgenic NT:T leaves had many DETs shared with the transgenic NT:T leaves, but very few with the transgenic NT:T roots. Interestingly, a number of these shared DETs belong to hormone pathway genes, concurring with the content changes of hormone metabolites in both transgenic and non-transgenic leaves of the NT:T plants. These results suggest that phytohormones induced by
VcFT
-OX in the transgenic leaves might serve as part of the signals that resulted in early flowering in both transgenic plants and the non-transgenic NT:T scions.
Key message
Significant differences in phytohormone profiles existed among the normal tree and two sterile mutant trees in interior Douglas-fir. Stem injection of gibberellin A
4
and A
7
induced male ...cone formation in one of the two genotypes of sterile trees.
Two sterile genotypes of interior Douglas-fir (
Pseudotsuga menziesii
var.
glauca
(Beissn.) Franco) were analyzed. The phenotype of these mutant trees is characterized by compact internodes, stunted vegetative growth and an inability to initiate male or female cone buds. Long shoots were sampled at the stage prior to cone bud initiation in both sterile and wild type trees. Multiple phytohormones and their selected metabolites were analyzed using high-performance liquid chromatography–electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Compared with concentrations in wild-type samples, levels of total quantifiable cytokinins were about half (51.9%) in samples of sterile trees. In particular, levels of both
trans
-zeatin riboside and isopentenyl adenosine were lower. Concentrations of abscisic acid (ABA)-related metabolites, especially ABA-glucose ester, were higher (1.4-fold) in sterile trees. Total quantifiable gibberellins were about one-third (28.3%) lower in the sterile trees: concentrations of GA
34
were significantly lower. There were no significant differences in concentrations of indole-3-acetic acid (IAA) or its conjugated form, IAA-aspartate. After stem injection of GA
4+7
, male cone formation was induced in one of the sterile genotypes. Gibberellin injection also caused the vegetative growth phenotype to change. Branches expanded to approximately five times their previous size in years past and their internodes showed more normal spacing. With their unique phytohormone profiles, these sterile mutants of Douglas-fir could provide a valuable research system for further exploration of molecular and physiological regulations during conifer reproduction.
Seaweeds and their extracts have been used for centuries in agriculture to improve plant growth and impart stress tolerance. There has been historical evidence that phytohormones present in seaweeds ...lead to these effects, but questions of this mode of action have always been raised. By quantifying phytohormones in seaweed extracts coupled with the use of phytohormone biosynthetic and insensitive mutants, we conclude that the phytohormone levels present within the extracts are insufficient to cause significant effects in plants when extracts are applied at recommended rates. However, components within seaweed extracts may modulate innate pathways for the biosynthesis of phytohormones in plants. Phytohormone profiles of plant tissue extracts were analyzed following root application of a commercial seaweed extract produced from Ascophyllum nodosum (ANE) to in vitro-grown Arabidopsis plants. We found an increase in total concentration of cytokinins (CKs), in particular, of trans-zeatin-type CKs, 24 and 96 h after ANE application, with an increase in cis-zeatin-type CKs observed at 144 h. Concomitantly, increases in abscisic acid (ABA) and ABA catabolite levels were observed whereas auxin levels were reduced. Additionally, the profile of transcripts revealed that CK biosynthetic genes were upregulated, whereas the CK catabolic genes were repressed at 24 and 96 h following ANE application. Not surprisingly, the transcripts of ABA biosynthetic genes were increased whereas the auxin biosynthetic genes were repressed. These corroborated findings are the first to help explain the underlying physiological benefits derived from the application of ANE to plants.
We tested the hypotheses that responses to the mountain pine beetle fungal associate Grosmannia clavigera will differ between the evolutionarily co‐evolved host lodgepole pine (Pinus contorta var. ...latifolia) and the naïve host jack pine (Pinus banksiana) and that these responses will be influenced by water availability. G. clavigera inoculation resulted in more rapid stem lesion development in lodgepole than in jack pine; water deficit delayed lesion development in both species. Decreased hydraulic conductivity was observed in inoculated lodgepole pine seedlings, likely because of tracheid occlusion by fungal hyphae and/or metabolite accumulation. Drought but not inoculation significantly impacted bark abscisic acid levels. Jasmonic and salicylic acid were implicated in local and systemic responses of both species to G. clavigera, with salicylic acid appearing to play a greater role in jack pine response to G. clavigera than lodgepole pine. Water deficit increased constitutive levels and/or attenuated induced responses to G. clavigera for several monoterpenes in lodgepole but not jack pine. Instead, inoculation of well‐watered but not water deficit jack pine resulted in a greater number of xylem resin ducts. These findings reveal mechanisms underlying differences in G. clavigera‐induced responses between lodgepole and jack pine hosts, and how water availability modulates these responses.
Western North America is currently experiencing the largest mountain pine beetle epidemic in recorded history; in recent years, this destructive forest pest has undergone host range expansion to jack pine, a boreal forest species. We have examined the effect of water limitation on responses of the evolutionarily co‐evolved host lodgepole pine and the naïve host jack pine, focusing on delineating similarities and differences in responses to inoculation with a mountain pine beetle fungal associate, Grosmannia clavigera. These species show different physiological responses to water limitation and that water deficit alters both constitutive and induced defences. Hormone profiles correlate with treatment‐associated differences in induced defences, and hormone crosstalk may modulate the patterns of induced defences that we observed in this study.
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