scholarly journals Identification of MBW Complex Components Implicated in the Biosynthesis of Flavonoids in Woodland Strawberry

2021 ◽  
Vol 12 ◽  
Author(s):  
Pengbo Xu ◽  
Liang Wu ◽  
Minghao Cao ◽  
Chao Ma ◽  
Kun Xiao ◽  
...  
Keyword(s):  
Flavonoid Biosynthesis ◽  
Qrt Pcr ◽  
Woodland Strawberry ◽  
The Family ◽  
Flavonoids Biosynthesis ◽  
Pcr Assays ◽  
Myb Proteins ◽  
R2r3 Myb ◽  
Green Stage ◽  
Mbw Complex

Flavonoids belong to the family of polyphenolic secondary metabolites and contribute to fruit quality traits. It has been shown that MBW complexes (MYB-bHLH-WD40) regulate the flavonoids biosynthesis in different plants, but only a limited number of MBW complexes have been identified in strawberry species in general. In this study, we identified 112 R2R3-MYB proteins in woodland strawberry; 12 of them were found to have potential functions in regulating flavonoids biosynthesis by phylogenetic analysis. qRT-PCR assays showed that FvMYB3, FvMYB9, FvMYB11, FvMYB22, FvMYB64, and FvMYB105 mostly expressed at green stage of fruit development, aligned with proanthocyanidins accumulation; FvMYB10 and FvMYB41 showed higher expression levels at turning and ripe stages, aligned with anthocyanins accumulation. These results suggest that different MYBs might be involved in flavonoids biosynthesis at specific stages. Furthermore, FvMYB proteins were demonstrated to interact with FvbHLH proteins and induce expression from the promoters of CHS2 and DFR2 genes, which encode key enzymes in flavonoids biosynthesis. The co-expression of FvMYB and FvbHLH proteins in strawberry fruits also promoted the accumulation of proanthocyanidins. These findings confirmed and provided insights into the biofunction of MBW components in the regulation of flavonoid biosynthesis in woodland strawberry.

scholarly journals NtMYB3, an R2R3-MYB from Narcissus, Regulates Flavonoid Biosynthesis

2019 ◽  
Vol 20 (21) ◽  
pp. 5456 ◽  
Author(s):  
Muhammad Anwar ◽  
Weijun Yu ◽  
Hong Yao ◽  
Ping Zhou ◽  
Andrew C. Allan ◽  
...  
Keyword(s):  
Transgenic Tobacco ◽  
Flavonoid Biosynthesis ◽  
Pcr Analysis ◽  
Wild Type ◽  
Narcissus Tazetta ◽  
Over Expression ◽  
Qrt Pcr ◽  
Red Color ◽  
R2r3 Myb ◽  
R2r3 Myb Transcription Factors

R2R3-MYB transcription factors play important roles in the regulation of plant flavonoid metabolites. In the current study, NtMYB3, a novel R2R3-MYB transcriptional factor isolated from Chinese narcissus (Narcissus tazetta L. var. chinensis), was functionally characterized. Phylogenetic analysis indicated that NtMYB3 belongs to the AtMYB4-like clade, which includes repressor MYBs involved in the regulation of flavonoid biosynthesis. Transient assays showed that NtMYB3 significantly reduced red pigmentation induced by the potato anthocyanin activator StMYB-AN1 in agro-infiltrated leaves of tobacco. Over-expression of NtMYB3 decreased the red color of transgenic tobacco flowers, with qRT-PCR analysis showing that NtMYB3 repressed the expression levels of genes involved in anthocyanin and flavonol biosynthesis. However, the proanthocyanin content in flowers of transgenic tobacco increased as compared to wild type. NtMYB3 showed expression in all examined narcissus tissues; the expression level in basal plates of the bulb was highest. A 968 bp promoter fragment of narcissus FLS (NtFLS) was cloned, and transient expression and dual luciferase assays showed NtMYB3 repressed the promoter activity. These results reveal that NtMYB3 is involved in the regulation of flavonoid biosynthesis in narcissus by repressing the biosynthesis of flavonols, and this leads to proanthocyanin accumulation in the basal plate of narcissus.

scholarly journals Regulation of flavonoid biosynthesis in representatives of the tribe Phaseoleae DC.

2021 ◽  
Vol 4 (3) ◽  
pp. 15-25
Author(s):  
E. A. Krylova ◽  
A. S. Mikhailova
Keyword(s):  
Transcription Factors ◽  
Flavonoid Biosynthesis ◽  
Plant Tissues ◽  
Structural Genes ◽  
Genetic Mechanisms ◽  
Pigment Biosynthesis ◽  
Dietary Value ◽  
R2r3 Myb ◽  
Functional Components ◽  
Mbw Complex

Flavonoids play a crucial role in plant metabolism. Many of them have antioxidant activity, and they are also pigments that render a variety of colors to plant tissues. Foods rich in flavonoid compounds are considered as functional components of a healthy diet. Currently, there is an increased interest in studying genetic mechanisms underlying the coloration of plants. Flavonoid biosynthesis pathways are controlled by two groups of genes. Structural genes encode enzymes, while regulatory genes are responsible for transcription factors that activate the expression of structural genes. Transcription factors that belong to R2R3-Myb, bHLH-Myc and WDR families form the ternary MBW complex, which is involved in regulating the expression of structural genes of flavonoid biosynthesis. The mechanisms of regulation of the anthocyanins and proanthocyanidin biosynthesis by the MBW complex are described in detail for the model plant Arabidopsis thaliana L. This review summarizes data on the regulation of phenolic pigment biosynthesis and the features of phenolic pigment accumulation in plant tissues in the main representatives of the Phaseoleae tribe: soybean Glycine max (L.) Merr., common bean Phaseolus vulgaris L., adzuki bean Vigna angularis (Willd.) Ohwi & Ohashi, and cowpea V. unguiculata (L.) Walp. The species discussed in this review are the most important food legumes in many countries of the world and they comprise the staple food in diets of millions of people. Identification and characterization of the genes controlling the flavonoid biosynthesis pathways are necessary for successful breeding of modern varieties with an increased dietary value. Identification of the flavonoid accumulation patterns is essential for solving the problem of broadening the diversity of plant products.

scholarly journals NtbHLH1, a JAF13-like bHLH, interacts with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yuxin Fan ◽  
Jiayu Peng ◽  
Jiacheng Wu ◽  
Ping Zhou ◽  
Ruijie He ◽  
...  
Keyword(s):  
Flavonoid Biosynthesis ◽  
Transcriptional Level ◽  
Flavonoid Pathway ◽  
Regulation Of Expression ◽  
Over Expression ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Regulatory Complex ◽  
Positive Regulators ◽  
R2r3 Myb

Abstract Background Flavonoid biosynthesis in plants is primarily regulated at the transcriptional level by transcription factors modulating the expression of genes encoding enzymes in the flavonoid pathway. One of the most studied transcription factor complexes involved in this regulation consists of a MYB, bHLH and WD40. However, in Chinese Narcissus (Narcissus tazetta L. var. chinensis), a popular monocot bulb flower, the regulatory mechanism of flavonoid biosynthesis remains unclear. Results In this work, genes related to the regulatory complex, NtbHLH1 and a R2R3-MYB NtMYB6, were cloned from Chinese Narcissus. Phylogenetic analysis indicated that NtbHLH1 belongs to the JAF13 clade of bHLH IIIf subgroup, while NtMYB6 was highly homologous to positive regulators of proanthocyanidin biosynthesis. Both NtbHLH1 and NtMYB6 have highest expression levels in basal plates of Narcissus, where there is an accumulation of proanthocyanidin. Ectopic over expression of NtbHLH1 in tobacco resulted in an increase in anthocyanin accumulation in flowers, and an up-regulation of expression of the endogenous tobacco bHLH AN1 and flavonoid biosynthesis genes. In contrast, the expression level of LAR gene was significantly increased in NtMYB6-transgenic tobacco. Dual luciferase assays showed that co-infiltration of NtbHLH1 and NtMYB6 significantly activated the promoter of Chinese Narcissus DFR gene. Furthermore, a yeast two-hybrid assay confirmed that NtbHLH1 interacts with NtMYB6. Conclusions Our results suggest that NtbHLH1 may function as a regulatory partner by interacting directly with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus.

scholarly journals Chorionic Villous Mesenchymal Stem Cells Derived Exosomes Deliver miR-135b-5p to Trophoblasts, Promoting their Proliferation and Invasion by Targeting TXNIP via β-Catenin Pathway

2020 ◽  
Author(s):  
Yijing Chu ◽  
Yan Zhang ◽  
Guoqiang Gao ◽  
Jun Zhou ◽  
Yang Lv ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Tissue Injury ◽  
Luciferase Reporter ◽  
Rna Seq ◽  
Qrt Pcr ◽  
Reporter Assays ◽  
Pcr Assays ◽  
Proliferation And Invasion

Abstract Background: Human chorionic villous mesenchymal stem cells (CV-MSCs) are found to be a promising and effective treatment for tissue injury. Trophoblast dysfunction during pregnancies is significantly involved in the pathogenesis of preeclampsia (PE). This work was to understand how CV-MSCs regulated trophoblast function. Methods: In this study, we treated trophoblasts with CV-MSC-derived exosomes and RNA-seq analysis was used to understand the changes in trophoblasts. We examined the levels of TXNIP and β-catenin in trophoblasts by immunohistochemistry, western blot and qRT-PCR assays. Luciferase reporter assays and qRT-PCR assays were used to understand the role of miR135b-5p in the effects of CV-MSC-derived exosomes. The growth and invasion of trophoblasts was evaluated with the CCK-8 and transwell assays. Results: The treatment markedly enhanced the trophoblast proliferation and invasion. Furthermore, a significant decrease of TXNIP expression and inactivation of the β-catenin pathway in CV-MSCs exosomes-treated trophoblasts was observed. Consistent with these findings, TXNIP inhibition exhibited the same effect of promoting trophoblast proliferation and invasion as induced by CV-MSC-derived exosomes, also with the accompaniment of inactivation of β-catenin pathway. In addition, overexpression of TXNIP activated the β-catenin pathway in trophoblasts, and reduced the proliferation and invasion of trophoblasts. Importantly, miR135b-5p was found to be highly expressed in CV-MSC exosomes and interact with TXNIP. The miR-135b-5p overexpression significantly elevated the proliferation and invasion of trophoblasts, which could be attenuated by TXNIP overexpression. Conclusion: Our results suggest that TXNIP-dependent β-catenin pathway inactivation mediated by miR135b-5p which is delivered by CV-MSC-derived exosomes could promote the proliferation and invasion of trophoblasts.

scholarly journals A New Hendra Virus Genotype Found in Australian Flying Foxes

2021 ◽  
Author(s):  
Jianning Wang ◽  
Danielle E Anderson ◽  
Kim Halpin ◽  
Xiao Hong ◽  
Honglei Chen ◽  
...  
Keyword(s):  
Genetic Relatedness ◽  
Phylogenetic Analyses ◽  
Inflammatory Lesion ◽  
Hendra Virus ◽  
Virus Genotype ◽  
Flying Foxes ◽  
Qrt Pcr ◽  
Genotype 2 ◽  
Pcr Assays ◽  
Flying Fox

Abstract Background Hendra virus (HeV) has caused lethal disease outbreaks in humans and horses in Australia. Pteropid bats (flying foxes) are the wildlife reservoir from which the virus was first isolated in 1996. Following a heat stress mortality event in Australian flying foxes in 2013, a novel HeV variant was discovered. This study describes the subsequent surveillance of Australian flying foxes for this novel virus over a nine year period using qRT-PCR testing of bat tissues submitted primarily for Australian bat lyssavirus (ABLV) diagnosis. Genome sequencing and characterisation of the novel HeV variant was also undertaken. Methods Spleen and kidney samples harvested from flying fox carcasses were initially screened with two real-time qRT-PCR assays specific for the prototype HeV. Two additional qRT-PCR assays were developed specific for the HeV variant first detected in samples from a flying fox in 2013. Next-generation sequencing and virus isolation was attempted from selected samples to further characterise the new virus. Results Since 2013, 98 flying foxes were tested and 11 were positive for the new HeV variant. No samples were positive for the original HeV. Ten of the positive samples were from grey-headed flying foxes (GHFF, Pteropus poliocephalus), however this species was over-represented in the opportunistic sampling (83% of bats tested were GHFF). The positive GHFF samples were collected from Victoria and South Australia and one positive Little red flying fox (LRFF, Pteropus scapulatus) was collected from Western Australia. Immunohistochemistry (IHC) confirmed the presence of henipavirus antigen, associated with an inflammatory lesion in cardiac blood vessels of one GHFF. Positive samples were sequenced and the complete genome was obtained from three samples. When compared to published HeV genomes, there was 84% sequence identity at the nucleotide level. Based on phylogenetic analyses, the newly detected HeV belongs to the HeV species but occupies a distinct lineage. We have therefore designated this virus HeV genotype 2 (HeV-G2). Attempts to isolate virus from PCR positive samples have not been successful. Conclusions A novel HeV genotype (HeV-G2) has been identified in two flying fox species submitted from three states in Australia, indicating that the level of genetic diversity for HeV is broader than first recognised. Given its high genetic relatedness to HeV, HeV-G2 should be considered a zoonotic pathogen.

The R2R3-MYB, bHLH, WD40, and related transcription factors in flavonoid biosynthesis

2012 ◽  
Vol 13 (1) ◽  
pp. 75-98 ◽  
Author(s):  
Lei Zhao ◽  
Liping Gao ◽  
Hongxue Wang ◽  
Xiaotian Chen ◽  
Yunsheng Wang ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Flavonoid Biosynthesis ◽  
R2r3 Myb

scholarly journals Temporospatial Flavonoids Metabolism Variation in Ginkgo biloba Leaves

2020 ◽  
Vol 11 ◽  
Author(s):  
Ying Guo ◽  
Tongli Wang ◽  
Fang-Fang Fu ◽  
Yousry A. El-Kassaby ◽  
Guibin Wang
Keyword(s):  
Ginkgo Biloba ◽  
Molecular Mechanisms ◽  
Developmental Stages ◽  
Early Stage ◽  
Sunshine Duration ◽  
Flavonoid Biosynthesis ◽  
Flavonoid Glycosides ◽  
Biosynthesis Pathway ◽  
Flavonoids Biosynthesis ◽  
Flavonoid Biosynthesis Pathway

Ginkgo (Ginkgo biloba L.) is a high-value medicinal tree species characterized by its flavonoids beneficial effects that are abundant in leaves. We performed a temporospatial comprehensive transcriptome and metabolome dynamics analyses of clonally propagated Ginkgo plants at four developmental stages (time: May to August) across three different environments (space) to unravel leaves flavonoids biosynthesis variation. Principal component analysis revealed clear gene expression separation across samples from different environments and leaf-developmental stages. We found that flavonoid-related metabolism was more active in the early stage of leaf development, and the content of total flavonoid glycosides and the expression of some genes in flavonoid biosynthesis pathway peaked in May. We also constructed a co-expression regulation network and identified eight GbMYBs and combining with other TF genes (3 GbERFs, 1 GbbHLH, and 1 GbTrihelix) positively regulated the expression of multiple structural genes in the flavonoid biosynthesis pathway. We found that part of these GbTFs (Gb_11316, Gb_32143, and Gb_00128) expressions was negatively correlated with mean minimum temperature and mean relative humidity, while positively correlated with sunshine duration. This study increased our understanding of the molecular mechanisms of flavonoids biosynthesis in Ginkgo leaves and provided insight into the proper production and management of Ginkgo commercial plantations.

scholarly journals Genome-Wide Analysis of the MYB Transcription Factor Superfamily in Physcomitrella patens

2020 ◽  
Vol 21 (3) ◽  
pp. 975 ◽  
Author(s):  
Xiaojun Pu ◽  
Lixin Yang ◽  
Lina Liu ◽  
Xiumei Dong ◽  
Silin Chen ◽  
...  
Keyword(s):  
Stress Responses ◽  
Physcomitrella Patens ◽  
Myb Transcription Factor ◽  
Rna Seq ◽  
Genome Wide ◽  
Terrestrial Environments ◽  
Gene Structures ◽  
Myb Genes ◽  
Myb Proteins ◽  
R2r3 Myb

MYB transcription factors (TFs) are one of the largest TF families in plants to regulate numerous biological processes. However, our knowledge of the MYB family in Physcomitrella patens is limited. We identified 116 MYB genes in the P. patens genome, which were classified into the R2R3-MYB, R1R2R3-MYB, 4R-MYB, and MYB-related subfamilies. Most R2R3 genes contain 3 exons and 2 introns, whereas R1R2R3 MYB genes contain 10 exons and 9 introns. N3R-MYB (novel 3RMYB) and NR-MYBs (novel RMYBs) with complicated gene structures appear to be novel MYB proteins. In addition, we found that the diversity of the MYB domain was mainly contributed by domain shuffling and gene duplication. RNA-seq analysis suggested that MYBs exhibited differential expression to heat and might play important roles in heat stress responses, whereas CCA1-like MYB genes might confer greater flexibility to the circadian clock. Some R2R3-MYB and CCA1-like MYB genes are preferentially expressed in the archegonium and during the transition from the chloronema to caulonema stage, suggesting their roles in development. Compared with that of algae, the numbers of MYBs have significantly increased, thus our study lays the foundation for further exploring the potential roles of MYBs in the transition from aquatic to terrestrial environments.

scholarly journals Real-time reverse transcription PCR (qRT-PCR) and its potential use in clinical diagnosis

2005 ◽  
Vol 109 (4) ◽  
pp. 365-379 ◽  
Author(s):  
Stephen A. Bustin ◽  
Reinhold Mueller
Keyword(s):  
Real Time ◽  
Reverse Transcription ◽  
Therapy Monitoring ◽  
Clinical Diagnostics ◽  
Clinical Diagnostic Laboratory ◽  
Diagnostic Laboratory ◽  
Qrt Pcr ◽  
Reverse Transcription Pcr ◽  
Clinical Diagnostic ◽  
Pcr Assays

qRT-PCR (real-time reverse transcription-PCR) has become the benchmark for the detection and quantification of RNA targets and is being utilized increasingly in novel clinical diagnostic assays. Quantitative results obtained by this technology are not only more informative than qualitative data, but simplify assay standardization and quality management. qRT-PCR assays are most established for the detection of viral load and therapy monitoring, and the development of SARS (severe acute respiratory syndrome)-associated coronavirus qRT-PCR assays provide a textbook example of the value of this technology for clinical diagnostics. The widespread use of qRT-PCR assays for diagnosis and the detection of disease-specific prognostic markers in leukaemia patients provide further examples of their usefulness. Their value for the detection of disease-associated mRNA expressed by circulating tumour cells in patients with solid malignancies is far less apparent, and the clinical significance of results obtained from such tests remains unclear. This is because of conceptual reservations as well as technical limitations that can interfere with the diagnostic specificity of qRT-PCR assays. Therefore, although it is evident that qRT-PCR assay has become a useful and important technology in the clinical diagnostic laboratory, it must be used appropriately and it is essential to be aware of its limitations if it is to fulfil its potential.

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