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1.
New Phytol ; 238(5): 2016-2032, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36792969

RESUMO

Quercus dentata Thunb., a dominant forest tree species in northern China, has significant ecological and ornamental value due to its adaptability and beautiful autumn coloration, with color changes from green to yellow into red resulting from the autumnal shifts in leaf pigmentation. However, the key genes and molecular regulatory mechanisms for leaf color transition remain to be investigated. First, we presented a high-quality chromosome-scale assembly for Q. dentata. This 893.54 Mb sized genome (contig N50 = 4.21 Mb, scaffold N50 = 75.55 Mb; 2n = 24) harbors 31 584 protein-coding genes. Second, our metabolome analyses uncovered pelargonidin-3-O-glucoside, cyanidin-3-O-arabinoside, and cyanidin-3-O-glucoside as the main pigments involved in leaf color transition. Third, gene co-expression further identified the MYB-bHLH-WD40 (MBW) transcription activation complex as central to anthocyanin biosynthesis regulation. Notably, transcription factor (TF) QdNAC (QD08G038820) was highly co-expressed with this MBW complex and may regulate anthocyanin accumulation and chlorophyll degradation during leaf senescence through direct interaction with another TF, QdMYB (QD01G020890), as revealed by our further protein-protein and DNA-protein interaction assays. Our high-quality genome assembly, metabolome, and transcriptome resources further enrich Quercus genomics and will facilitate upcoming exploration of ornamental values and environmental adaptability in this important genus.


Assuntos
Antocianinas , Quercus , Antocianinas/metabolismo , Quercus/genética , Quercus/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Transcriptoma/genética , Fatores de Transcrição/metabolismo , Metaboloma , Pigmentação/genética , Cromossomos , Glucosídeos , Cor
2.
Anal Bioanal Chem ; 415(17): 3559-3569, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37198360

RESUMO

The peroxidase-like activity of Ti3C2 nanosheets (Ti3C2 NSs) was evaluated by catalytic oxidation of colorless o-phenylenediamine (OPD) into orange-yellow 2,3-diaminophenazine (DAP) with the aid of H2O2. The catalytic behavior followed the typical Michaelis-Menten kinetics. Systematic studies about the catalytic activity of Ti3C2 NSs including cytochrome C (Cyt C) electron transfer experiments, radical capture experiments, and fluorescence analysis were conducted, revealing that the catalytic mechanism of Ti3C2 NSs was attributed to nanozyme-accelerated electron transfer between substrates and nanozyme-promoted generation of active species (superoxide anion free radical (·O2-) and holes (h+)). Single-stranded DNA (ssDNA) inhibited the peroxidase-like activity of Ti3C2 NSs, and the reduced catalytic activity was ascribed to DNA-hindered substrate accessibility to nanozyme surface. Based on the DNA controllable peroxidase-mimicking activity of Ti3C2 NSs, taking microcystin-LR (MC-LR) aptamer as an example, a label-free colorimetric aptasensor was proposed for the sensitive detection of MC-LR. The colorimetric aptasensor showed a wide linear range (0.01-60 ng mL-1), low limit of detection (6.5 pg mL-1), and high selectivity. The practicality of the colorimetric aptasensor was demonstrated by detecting different levels of MC-LR in spiked real water samples; satisfactory recoveries (97.2-102.1%) and low relative standard deviations (1.16-3.72%) were obtained.


Assuntos
Técnicas Biossensoriais , Colorimetria , Peróxido de Hidrogênio/análise , Titânio , DNA de Cadeia Simples , Peroxidases , Limite de Detecção
3.
Mikrochim Acta ; 189(10): 369, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063228

RESUMO

Ag nanoparticle-decorated Ti3C2 nanosheets (AgNPs@Ti3C2 NSs) were facilely synthesized via a self-reduction approach, in which Ti3C2 NSs acted as both reductant and supporter. The AgNPs@Ti3C2 NS nanocomposite exhibited excellent peroxidase-like activity with o-phenylenediamine (OPD) and H2O2 as substrates. The catalytic behavior followed the typical Michaelis-Menten kinetics; Michaelis constant (Km) and maximum initial velocity (Vmax) for OPD were 0.263 mM and 43.2 × 10-8 M-1 s, indicating high affinity and high catalytic efficiency towards OPD. The catalytic mechanism was revealed to be an accelerated electron transfer process. Based on the inhibition effect on the peroxidase-like activity of AgNPs@Ti3C2 NSs, a simple, fast, and sensitive colorimetric method for detection of low-weight biothiols (cysteine (Cys), homocysteine (Hcy), and glutathione (GSH)) was developed by measuring the absorbance at 425 nm. The colorimetric method displayed wide linear range (50 nM to 50 µM for Cys, 10 nM to 250 µM for Hcy, 10 nM to 50 µM for GSH), low limit of detection (48.5 nM for Cys, 5.5 nM for Hcy, 7.0 nM for GSH), and good selectivity and short assay time (3 min). Moreover, the feasibility of this colorimetric sensor was demonstrated by accurately determining Cys in diluted human serum samples; good recovery (95.9-101.0%) and low relative standard deviations (2.8-4.9%) were obtained, showing great promise for point-of-care test in clinical samples.


Assuntos
Colorimetria , Nanopartículas Metálicas , Colorimetria/métodos , Cisteína , Glutationa , Humanos , Peróxido de Hidrogênio , Oxirredutases , Peroxidase , Peroxidases , Prata , Titânio
4.
J Neuroinflammation ; 14(1): 73, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28359334

RESUMO

BACKGROUND: Traumatic brain injury (TBI) triggers both immediate (primary) and long-term (secondary) tissue damages. Secondary damages can last from hours to days or even a lifetime. Secondary damages implicate several mechanisms, including influence of inflammatory mediators, mainly cytokines, on excitability of ion channels. However, studies should further explore the effects of inflammatory cytokines on voltage-gated sodium channels (VGSCs) and excitability in distal intact neurons. METHODS: Mixed cultures of mouse cortical astrocytes and neurons were subjected to mechanical injury (trauma) to mimic TBI in vitro. Expression of various cytokines in these cultures were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. A trauma-conditioned medium with or without brain-derived neurotrophic factor (BDNF) was added to mouse primary cortical neurons for 6 and 24 h to mimic combined effects of multiple inflammatory cytokines on VGSCs. Spike behaviors of distal intact neurons were examined by whole-cell patch-clamp recordings. RESULTS: Mechanical injury in mixed cortical neuron-astrocyte cultures significantly increased expression levels of multiple cytokines, including interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, monocyte chemoattractant protein-1, chemokine (C-C motif) ligand-5, IL-10, and transforming growth factor-ß1, at 6 and 24 h after injury. Incubation in trauma-conditioned medium increased functional VGSCs in neuronal membranes and Na+ currents. Enhanced VGSCs were almost completely abolished by BDNF, and reinforcement of Na+ currents was also reduced in a dose-dependent manner. BDNF (30 ng/mL) also significantly reversed reduced neuronal cell viability, which was induced by medium conditioned at 6 h. At 6 and 24 h, trauma-conditioned medium significantly increased spike frequency but not spike threshold. CONCLUSIONS: In TBI, the combined effect of inflammatory cytokines is directly involved in VGSC, Na+ current, and excitability dysfunction in distal intact neurons. BDNF may partly exert neuroprotective effects by maintaining balance of VGSC function in distal intact neurons.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Citocinas/metabolismo , Neurônios/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Córtex Cerebral/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
5.
J Neuroinflammation ; 12: 126, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26112872

RESUMO

BACKGROUND: Previous studies showed that TNF-α could activate voltage-gated Na(+) channels (VGSCs) in the peripheral nervous system (PNS). Since TNF-α is implicated in many central nervous system (CNS) diseases, we examined potential effects of TNF-α on VGSCs in the CNS. METHODS: Effects of TNF-α (1-1000 pg/mL, for 4-48 h) on VGSC currents were examined using whole-cell voltage clamp and current clamp techniques in primary culture of mouse cortical neurons. Expression of Nav1.1, Nav1.2, Nav1.3, and Nav1.6 were examined at both the mRNA and protein levels, prior to and after TNF-α exposure. RESULTS: TNF-α increased Na(+) currents by accelerating the activation of VGSCs. The threshold for action potential (AP) was decreased and firing rate were increased. VGSCs were up-regulated at both the mRNA and protein levels. The observed effects of TNF-α on Na(+) currents were inhibited by pre-incubation with the NF-κB inhibitor BAY 11-7082 (1 µM) or the p38 mitogen-activated protein kinases (MAPK) inhibitor SB203580 (1 µM). CONCLUSIONS: TNF-α increases Na(+) currents by accelerating the channel activation as well as increasing the expression of VGSCs in a mechanism dependent upon NF-κB and p38 MAPK signal pathways in CNS neurons.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos , Canais de Sódio Disparados por Voltagem/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Relação Dose-Resposta a Droga , Imidazóis/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , NF-kappa B/fisiologia , Neurônios/citologia , Nitrilas/farmacologia , Técnicas de Patch-Clamp , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Sulfonas/farmacologia , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
6.
Biochem Biophys Res Commun ; 450(1): 55-60, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24875357

RESUMO

Typical antipsychotics are characterized by extrapyramidal syndrome (EPS). Previous studies demonstrated that typical antipsychotics could inhibit neuronal voltage-gated sodium channel (VGSC). However, EPS typically emerge only upon prolonged exposure. As a result, we examined effects of haloperidol, a prototype typical antipsychotic, on neuronal VGSC upon incubation for varying duration. Briefly, VGSC currents were activated and recorded using a whole-cell patch-clamp technique in primary culture of mouse cortical neurons. VGSC activity was inhibited by acute haloperidol exposure (for minutes), but enhanced in a time- and concentration-dependent manner by chronic haloperidol exposure (for hours). The effects of chronic haloperidol were associated with increased expression of VGSC subunits as well as corresponding electrophysiological channel properties. In summary, we found enhanced VGSC currents upon chronic haloperidol exposure in cortical neurons in contrast to inhibition by acute haloperidol exposure. Such a results may contribute to EPS of typical antipsychotics.


Assuntos
Potenciais de Ação/fisiologia , Córtex Cerebral/fisiologia , Haloperidol/administração & dosagem , Ativação do Canal Iônico/fisiologia , Neurônios/fisiologia , Sódio/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Antipsicóticos/administração & dosagem , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Antagonistas de Dopamina/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos
7.
Anal Chim Acta ; 1306: 342599, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692792

RESUMO

BACKGROUND: Microcystin-leucine-arginine (MC-LR) produced by various cyanobacteria during harmful algal bloom poses serious threats to drinking water safety and human health. Conventional chromatography-based detection methods require expensive instruments and complicated sample pretreatment, limiting their application for on-site detection. Colorimetric aptasensors are simple and rapid, and are amenable to fast detection. However, they provide only one output signal, resulting in poor sensitivity and accuracy. Dual-channel ratiometric colorimetric method based on the peroxidase-like activity of nanozyme can achieve self-calibration by recording two reverse signals, providing significantly enhanced sensitivity and accuracy. RESULTS: CeO2 nanocages (CeO2 NCs) with tetra-enzyme mimetic activities (oxidase-, peroxidase-, catalase- and superoxide dismutase-like activities) were facilely synthesized using zeolitic imidazolate framework-67 (ZIF-67) as sacrificial template. The peroxidase-like activity of CeO2 NCs can be regulated by DNA, and it showed opposite response to two chromogenic substrates (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 3,3',5,5'-tetramethylbenzidine (TMB)), which was mainly attributed to the changed affinity. On the basis of MC-LR aptamer-tunable peroxidase-like activity of CeO2 NCs in TMB and ABTS channel, a dual-channel ratiometric colorimetric aptasensor was constructed for detection of MC-LR. Compared with conventional single-signal colorimetric assays, the proposed method showed lower limit of detection (0.66 pg mL-1) and significantly enhanced sensitivity. Moreover, the practicability of the ratiometric colorimetric assay was demonstrated by detecting MC-LR in real water samples, and satisfactory recoveries (94.9-101.9 %) and low relative standard deviations (1.6-6.3 %) were obtained. SIGNIFICANCE: This work presents a nanozyme-based ratiometric colorimetric aptasensor for MC-LR detection by recording the reverse responses of two chromogenic reactions. Benefiting from the self-calibration function, the method can achieve higher sensitivity and accuracy. The short detection time and practical application in real water samples show great potential for environmental monitoring.


Assuntos
Cério , Colorimetria , Toxinas Marinhas , Microcistinas , Microcistinas/análise , Colorimetria/métodos , Toxinas Marinhas/análise , Cério/química , Aptâmeros de Nucleotídeos/química , Limite de Detecção , Nanoestruturas/química , Técnicas Biossensoriais/métodos
8.
Int J Biol Macromol ; 260(Pt 1): 129448, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228204

RESUMO

The acquisition of high quality lyophilized IgY products, characterized by an aesthetically pleasing visage, heightened stability, and a marked preservation of activity, constitutes an indispensable pursuit in augmenting the safety and pragmatic utility of IgY. Within this context, an exploration was undertaken to investigate an innovative modality encompassing microwave freeze-drying (MFD) as a preparatory methodology of IgY. Morphological assessments revealed that both cryogenic freezing and subsequent MFD procedures resulted in aggregation of IgY, with the deleterious influence posed by the MFD phase transcending that of the freezing phase. The composite protective agent comprised of trehalose and mannitol engendered a safeguarding effect on the structural integrity of IgY, thereby attenuating reducing aggregation between IgY during the freeze-drying process. Enzyme-linked immunosorbent assay (ELISA) outcomes demonstrated a discernible correlation between IgY aggregation and a notable reduction in its binding affinity towards the pertinent antigen. Comparative analysis vis-à-vis the control sample delineated that when the trehalose-to-mannitol ratio was upheld at 1:3, a two-fold outcome was achieved: a mitigation of the collapse susceptibility within the final product as well as a deterrence of IgY agglomeration, concomitant with an elevated preservation rate of active antibodies (78.57 %).


Assuntos
Imunoglobulinas , Manitol , Trealose , Congelamento , Trealose/farmacologia , Trealose/química , Manitol/química , Liofilização/métodos
9.
Anal Methods ; 15(2): 221-227, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36541424

RESUMO

A recyclable peroxidase mimic Fe3O4@polydopamine/Prussian blue (Fe3O4@PDA/PB) composite was facilely prepared by coating PDA on an Fe3O4 nanoparticle core and in situ growth of PB nanoparticles on a PDA shell. The prepared Fe3O4@PDA/PB composite exhibited excellent peroxidase-like activity and can catalytically oxidize the colorless colorimetric substrate 3,3',5,5'-tetramethylbenzidine (TMB) into a blue colored product in the presence of H2O2 at 30 °C in 1 min. The catalytic mechanism was deduced to be the nanozyme-promoted generation of a hydroxyl radical (·OH), and the catalytic behavior followed the typical Michaelis-Menten kinetics. Based on Cr(VI)-boosted peroxidase-like activity of Fe3O4@PDA/PB, a simple and fast colorimetric method for detection of Cr(VI) was developed. Under the optimum conditions, the colorimetric method exhibited wider linear range (100 nM to 140 µM), low LOD (51.1 nM), good selectivity and short detection time (1 min). Moreover, the feasibility of the proposed colorimetric method was evaluated by determination of Cr(VI) in spiked tap water and lake water samples. Good recoveries (95.2-102.9%) and low relative standard deviations (RSDs) (1.6-4.4%) were obtained, showing great promise for practical use.


Assuntos
Colorimetria , Peroxidase , Colorimetria/métodos , Peróxido de Hidrogênio , Peroxidases
10.
Plant Commun ; 4(4): 100574, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-36906801

RESUMO

Most species have clearly defined distribution ranges and ecological niches. The genetic and ecological causes of species differentiation and the mechanisms that maintain species boundaries between newly evolved taxa and their progenitors are, however, less clearly defined. This study investigated the genetic structure and clines in Pinus densata, a pine of hybrid origin on the southeastern Tibetan Plateau, to gain an understanding of the contemporary dynamics of species barriers. We analyzed genetic diversity in a range-wide collection of P. densata and representative populations of its progenitors, Pinus tabuliformis and Pinus yunnanensis, using exome capture sequencing. We detected four distinct genetic groups within P. densata that reflect its migration history and major gene-flow barriers across the landscape. The demographies of these genetic groups in the Pleistocene were associated with regional glaciation histories. Interestingly, population sizes rebounded rapidly during interglacial periods, suggesting persistence and resilience of the species during the Quaternary ice age. In the contact zone between P. densata and P. yunnanensis, 3.36% of the analyzed loci (57 849) showed exceptional patterns of introgression, suggesting their potential roles in either adaptive introgression or reproductive isolation. These outliers showed strong clines along critical climate gradients and enrichment in a number of biological processes relevant to high-altitude adaptation. This indicates that ecological selection played an important role in generating genomic heterogeneity and a genetic barrier across a zone of species transition. Our study highlights the forces that operate to maintain species boundaries and promote speciation in the Qinghai-Tibetan Plateau and other mountain systems.


Assuntos
Pinus , Isolamento Reprodutivo , Tibet , Fluxo Gênico , Genômica , Pinus/genética
11.
Food Chem ; 404(Pt A): 134626, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444045

RESUMO

The preparation of egg yolk powder (EYP) with excellent solubility and high retention of active IgY is of great significance for increasing the added value and promoting the application of EYP. A new method of preparing EYP by microwave-assisted freeze-drying (MFD) was researched. Confocal laser scanning microscopy results demonstrated that the supplementation of excipients (sucrose, trehalose, and maltodextrin) could inhibit lipoproteins aggregation in egg yolk induced by freezing. Scanning electron microscopy indicated that drying further damaged the structure of lipoproteins in EYP, leading to lipid separation from it. FTIR and fluorescence spectra confirmed this finding, indicating that excipients enhance protein stability. Compared with conventional freeze-drying (FD), EYP prepared by MFD, particularly that containing excipients, had higher solubility (63 g/100 g), active antibody retention rate and shorter drying time. Therefore, excipients can significantly improve the solubility and stability of EYP and the retention rate of active IgY.


Assuntos
Dissacarídeos , Gema de Ovo , Pós , Micro-Ondas , Excipientes
12.
Front Plant Sci ; 14: 1122549, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968354

RESUMO

Wood decay resistance (WDR) is marking the value of wood utilization. Many trees of the Lauraceae have exceptional WDR, as evidenced by their use in ancient royal palace buildings in China. However, the genetics of WDR remain elusive. Here, through comparative genomics, we revealed the unique characteristics related to the high WDR in Lauraceae trees. We present a 1.27-Gb chromosome-level assembly for Lindera megaphylla (Lauraceae). Comparative genomics integrating major groups of angiosperm revealed Lauraceae species have extensively shared gene microsynteny associated with the biosynthesis of specialized metabolites such as isoquinoline alkaloids, flavonoid, lignins and terpenoid, which play significant roles in WDR. In Lauraceae genomes, tandem and proximal duplications (TD/PD) significantly expanded the coding space of key enzymes of biosynthesis pathways related to WDR, which may enhance the decay resistance of wood by increasing the accumulation of these compounds. Among Lauraceae species, genes of WDR-related biosynthesis pathways showed remarkable expansion by TD/PD and conveyed unique and conserved motifs in their promoter and protein sequences, suggesting conserved gene collinearity, gene expansion and gene regulation supporting the high WDR. Our study thus reveals genomic profiles related to biochemical transitions among major plant groups and the genomic basis of WDR in the Lauraceae.

13.
Front Plant Sci ; 14: 1273648, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900760

RESUMO

Terpenes and terpenoids are key natural compounds for plant defense, development, and composition of plant oil. The synthesis and accumulation of a myriad of volatile terpenoid compounds in these plants may dramatically alter the quality and flavor of the oils, which provide great commercial utilization value for oil-producing plants. Terpene synthases (TPSs) are important enzymes responsible for terpenic diversity. Investigating the differentiation of the TPS gene family could provide valuable theoretical support for the genetic improvement of oil-producing plants. While the origin and function of TPS genes have been extensively studied, the exact origin of the initial gene fusion event - it occurred in plants or microbes - remains uncertain. Furthermore, a comprehensive exploration of the TPS gene differentiation is still pending. Here, phylogenetic analysis revealed that the fusion of the TPS gene likely occurred in the ancestor of land plants, following the acquisition of individual C- and N- terminal domains. Potential mutual transfer of TPS genes was observed among microbes and plants. Gene synteny analysis disclosed a differential divergence pattern between TPS-c and TPS-e/f subfamilies involved in primary metabolism and those (TPS-a/b/d/g/h subfamilies) crucial for secondary metabolites. Biosynthetic gene clusters (BGCs) analysis suggested a correlation between lineage divergence and potential natural selection in structuring terpene diversities. This study provides fresh perspectives on the origin and evolution of the TPS gene family.

14.
Sci Data ; 10(1): 259, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37156769

RESUMO

Coriaria nepalensis Wall. (Coriariaceae) is a nitrogen-fixing shrub which forms root nodules with the actinomycete Frankia. Oils and extracts of C. nepalensis have been reported to be bacteriostatic and insecticidal, and C. nepalensis bark provides a valuable tannin resource. Here, by combining PacBio HiFi sequencing and Hi-C scaffolding techniques, we generated a haplotype-resolved chromosome-scale genome assembly for C. nepalensis. This genome assembly is approximately 620 Mb in size with a contig N50 of 11 Mb, with 99.9% of the total assembled sequences anchored to 40 pseudochromosomes. We predicted 60,862 protein-coding genes of which 99.5% were annotated from databases. We further identified 939 tRNAs, 7,297 rRNAs, and 982 ncRNAs. The chromosome-scale genome of C. nepalensis is expected to be a significant resource for understanding the genetic basis of root nodulation with Frankia, toxicity, and tannin biosynthesis.


Assuntos
Genoma de Planta , Magnoliopsida , Haplótipos , Magnoliopsida/genética , Anotação de Sequência Molecular , Filogenia , Cromossomos de Plantas
15.
Hortic Res ; 10(1): uhac241, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643737

RESUMO

The genus Rhododendron (Ericaceae), with more than 1000 species highly diverse in flower color, is providing distinct ornamental values and a model system for flower color studies. Here, we investigated the divergence between two parental species with different flower color widely used for azalea breeding. Gapless genome assembly was generated for the yellow-flowered azalea, Rhododendron molle. Comparative genomics found recent proliferation of long terminal repeat retrotransposons (LTR-RTs), especially Gypsy, has resulted in a 125 Mb (19%) genome size increase in species-specific regions, and a significant amount of dispersed gene duplicates (13 402) and pseudogenes (17 437). Metabolomic assessment revealed that yellow flower coloration is attributed to the dynamic changes of carotenoids/flavonols biosynthesis and chlorophyll degradation. Time-ordered gene co-expression networks (TO-GCNs) and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct flower pigmentation. B3 and ERF TFs were found dominating the gene regulation of carotenoids/flavonols characterized pigmentation in R. molle, while WRKY, ERF, WD40, C2H2, and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-flowered R simsii. This study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding.

16.
Talanta ; 248: 123607, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35661001

RESUMO

The existence of cyanotoxins poses serious threats to human health, it is highly desirable to develop specific and sensitive methods for rapid detection of cyanotoxins in food and water. Due to the distinct advantages of aptamer including high specificity, good stability and easy preparation, various aptamer-based sensors (aptasensors) have been proposed to promote the detection of cyanotoxins. In this review, we summarize recent advance in optical and electrochemical aptasensors for cyanotoxins sensing by integrating with versatile nanomaterials or innovative sensing strategies, such as colorimetric aptasensors, fluorescent aptasensors, surface enhancement Raman spectroscopy-based aptasensors, voltammetric aptasensors, electrochemical impedance spectroscopy-based aptasensors and photoelectrochemical aptasensors. We highlight the accomplishments and advancements of aptasensors with improved performance. Furthermore, the current challenges and future prospects in cyanotoxins detection are discussed from our perspectives, which we hope to provide more ideas for future researchers.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanoestruturas , Técnicas Biossensoriais/métodos , Toxinas de Cianobactérias , Técnicas Eletroquímicas/métodos , Humanos
17.
Hortic Res ; 8(1): 177, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34465761

RESUMO

Polyploidization plays a key role in plant evolution, but the forces driving the fate of homoeologs in polyploid genomes, i.e., paralogs resulting from a whole-genome duplication (WGD) event, remain to be elucidated. Here, we present a chromosome-scale genome assembly of tetraploid scarlet sage (Salvia splendens), one of the most diverse ornamental plants. We found evidence for three WGD events following an older WGD event shared by most eudicots (the γ event). A comprehensive, spatiotemporal, genome-wide analysis of homoeologs from the most recent WGD unveiled expression asymmetries, which could be associated with genomic rearrangements, transposable element proximity discrepancies, coding sequence variation, selection pressure, and transcription factor binding site differences. The observed differences between homoeologs may reflect the first step toward sub- and/or neofunctionalization. This assembly provides a powerful tool for understanding WGD and gene and genome evolution and is useful in developing functional genomics and genetic engineering strategies for scarlet sage and other Lamiaceae species.

18.
Hortic Res ; 8(1): 188, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354050

RESUMO

Ginger (Zingiber officinale) is one of the most valued spice plants worldwide; it is prized for its culinary and folk medicinal applications and is therefore of high economic and cultural importance. Here, we present a haplotype-resolved, chromosome-scale assembly for diploid ginger anchored to 11 pseudochromosome pairs with a total length of 3.1 Gb. Remarkable structural variation was identified between haplotypes, and two inversions larger than 15 Mb on chromosome 4 may be associated with ginger infertility. We performed a comprehensive, spatiotemporal, genome-wide analysis of allelic expression patterns, revealing that most alleles are coordinately expressed. The alleles that exhibited the largest differences in expression showed closer proximity to transposable elements, greater coding sequence divergence, more relaxed selection pressure, and more transcription factor binding site differences. We also predicted the transcription factors potentially regulating 6-gingerol biosynthesis. Our allele-aware assembly provides a powerful platform for future functional genomics, molecular breeding, and genome editing in ginger.

19.
Nat Commun ; 11(1): 5269, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077749

RESUMO

Azaleas (Ericaceae) comprise one of the most diverse ornamental plants, renowned for their cultural and economic importance. We present a chromosome-scale genome assembly for Rhododendron simsii, the primary ancestor of azalea cultivars. Genome analyses unveil the remnants of an ancient whole-genome duplication preceding the radiation of most Ericaceae, likely contributing to the genomic architecture of flowering time. Small-scale gene duplications contribute to the expansion of gene families involved in azalea pigment biosynthesis. We reconstruct entire metabolic pathways for anthocyanins and carotenoids and their potential regulatory networks by detailed analysis of time-ordered gene co-expression networks. MYB, bHLH, and WD40 transcription factors may collectively regulate anthocyanin accumulation in R. simsii, particularly at the initial stages of flower coloration, and with WRKY transcription factors controlling progressive flower coloring at later stages. This work provides a cornerstone for understanding the underlying genetics governing flower timing and coloration and could accelerate selective breeding in azalea.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta , Proteínas de Plantas/genética , Rhododendron/genética , Antocianinas/biossíntese , Vias Biossintéticas , Carotenoides/metabolismo , Cromossomos de Plantas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Família Multigênica , Proteínas de Plantas/metabolismo , Rhododendron/crescimento & desenvolvimento , Rhododendron/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 11(4): 288-90, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19374814

RESUMO

OBJECTIVE: To study serum levels of melatonin in children with epilepsy or febrile seizures in order to provide a basis for the treatment of epilepsy or febrile seizures with melatonin. METHODS: Serum melatonin levels were measured using ELISA in 15 children with simple febrile seizure (SFS), in 15 children with complex febrile seizure (CFS), in 15 children with epilepsy, and in 15 children with upper respiratory infections (control group). RESULTS: Serum melatonin levels in children with epilepsy (8.66+/-1.38 ng/L) or CFS (14.91+/-2.61 ng/L) were significant lower than those in the control group (23.93+/-2.01 ng/L) (P<0.01). The SFS group showed lower serum melatonin levels (20.72+/-2.54 ng/L) compared with the control group, but there were no statistical differences between the two groups. Serum melatonin levels in the epilepsy group were significantly lower than those in the CFS (P<0.05) and the SFS groups (P<0.01). CONCLUSIONS: Serum melatonin levels decreased in children with epilepsy or CFS. Supplement of exogenous melatonin might be a promising treatment for epilepsy and febrile seizures in children.


Assuntos
Epilepsia/sangue , Melatonina/sangue , Convulsões Febris/sangue , Criança , Pré-Escolar , Epilepsia/tratamento farmacológico , Feminino , Humanos , Lactente , Masculino , Melatonina/farmacologia , Melatonina/uso terapêutico
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