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1.
Plant Biol (Stuttg) ; 22(4): 615-622, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32160384

RESUMO

Phosphorus (P) is an important nutrient that can restrict plant growth. However, the influence of P deficiency on elemental homeostasis and application of the growth rate hypothesis in higher plants remain to be assessed. Two shrubs, Zygophyllum xanthoxylum and Nitraria tangutorum, were used as experiment material and subjected to five P addition treatments: 0, 17.5, 35.0, 52.5 and 70.0 mg P·kg-1 soil. The biomass and relative growth rate of Z. xanthoxylum did not change with altered P supply. There was no significant difference in P concentration among the treatments for Z. xanthoxylum, but N. tangutorum showed an upward trend. The P stoichiometric homeostasis of Z. xanthoxylum was higher than that of N. tangutorum. For Z. xanthoxylum, available P in the rhizosphere improved significantly under extreme P deficiency conditions, and P concentrations in all treatments were lower than in N. tangutorum, showing that Z. xanthoxylum had stronger P absorption and P utilization capacity. No relationships between growth rate and C:N:P ratios were found in Z. xanthoxylum. The strong P efficiency, and high and stable dry matter accumulation, are likely contributors in maintaining stoichiometric homeostasis. In addition, the relatively high biomass accumulation and high P utilization efficiency for Z. xanthoxylum does not support the growth rate hypothesis for this species.


Assuntos
Magnoliopsida , Fósforo , Zygophyllum , Biomassa , Magnoliopsida/metabolismo , Fósforo/metabolismo , Rizosfera , Solo/química , Zygophyllum/crescimento & desenvolvimento , Zygophyllum/metabolismo
2.
PLoS One ; 15(3): e0228563, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176700

RESUMO

Lead (Pb) and cadmium (Cd) are highly toxic and are widespread in agricultural soils, representing risks to plant and human health. In this study, Davidia involucrata was cultivated in soil with different concentrations of Pb and Cd and sampled after 90 days. We used ANOVA to analyse the photosynthesis of D. involucrata and the ability of Pb and Cd to enrich and migrate in roots, stems and leaves. Various results are described here. 1) Under individual and combined Pb and Cd stress, the accumulation factors in the roots were greater than 1, which was significantly greater than those in the stems and leaves (P < 0.05), and the translocation factors both were less than 1. The Pb and Cd enrichment ability of D. involucrata roots was significantly higher than that of stems and leaves, and the migration ability of the two heavy metals in D. involucrata was weak. 2) The Mg-dechelatase activities of chlorophyll degradation products increased under stress due to high concentrations of Pb and Cd. However, chlorophyllase activity was higher at relatively low concentrations of the two heavy metals (P < 0.05). δ-Aminolevulinic acid and porphobilinogen of chlorophyll synthesis products are easily converted to uroporphyrinogen III under low concentrations of Cd, which promotes the synthesis of chlorophyll. 3) The effect of Cd stress alone on the chlorophyll concentration was not significant. Under combined stress, concentrations of Pb and Cd in the range of 400~800 mg·kg-1 and 5~20 mg·kg-1 significantly promoted an increase in photosynthetic pigments (P < 0.05). 4) Inhibition of the net photosynthetic rate increased with increasing Pb and Cd concentrations under both individual and combined stress. In addition, the root of D. involucrata had a strong absorption and fixation effect on heavy metals, thereby reducing metal toxicity and improving the tolerance of D. involucrata to heavy metals.


Assuntos
Cádmio/toxicidade , Chumbo/toxicidade , Magnoliopsida/efeitos dos fármacos , Magnoliopsida/metabolismo , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/toxicidade , Cádmio/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Chumbo/metabolismo , Poluentes do Solo/metabolismo
3.
J Photochem Photobiol B ; 204: 111587, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32062387

RESUMO

Although the photothermal therapy (PTT) has achieved tremendous progress in the recent times, still it has to improve an extensive way to achieve the efficient targeted photothermal removal of the tumor cells. Owing to this requirement, we demonstrated a novel class of reduced graphene oxide based photothermal therapeutic agent for the ablation of lung cancer cells (A549). A single step bio facile fabrication of graphene nanosheets using Memecylon edule leaf extract intermediated reduction of Graphene Oxide (GO). This process does not include the utilization of any toxic or harmful reducing agents. The relative results of different characterizations of graphene oxide and Memecylon edule leaf extract RGO delivers a potential representation by excluding the groups containing oxygen from GO and consecutive stabilization of the developed RGO. The reduced GO functionalization with the oxidized polyphenols results in their stability by avoiding the aggregation. The poly phenol anchored Reduced Graphene Oxide (RGO) exhibited exceptional near-infrared (NIR) irradiation of the lung cancer cells directed in vitro to deliver cytotoxicity. In an area of restricted success in the treatment of cancer, the results of our translation can provide a path for designing targeted PTT agents and also responds to stimulus environment for the safe ablation of the devastating disease.


Assuntos
Grafite/química , Raios Infravermelhos , Nanoestruturas/química , Polifenóis/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cães , Química Verde , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Células Madin Darby de Rim Canino , Magnoliopsida/química , Magnoliopsida/metabolismo , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Fototerapia/métodos , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
4.
Chemosphere ; 249: 126113, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32062208

RESUMO

The widespread occurrence and distribution of organotin compounds (OTCs) in both marine and freshwater ecosystems has aroused considerable concerns in most countries worldwide. In this work, individual kinetics of the elimination of three butyltins and three phenyltins from C. demersum L. were systematically studied for over 240 h in clean water after a 48h period of accumulation. All OTCs were rapidly metabolized to nontoxic inorganic tin by C. demersum L. through stepwise debutylation or dephenylation. In addition to inorganic tin, monobutyltin (MBT) and monophenyltin (MPT) were the primary degradation products of tributyltin (TBT) and triphenyltin (TPT), with small amounts of dibutyltin (DBT) and diphenyltin (DPT), respectively, also being present. The estimated half-life of TPT (240 h) in C. demersum L. was longer than that of TBT (100 h), although the TPT was less hydrophobic. The corresponding degradation mechanisms may be attributed to a cascade of enzymatic reactions of CYP450 enzymes in C. demersum L. The pH played an important role in both plant growth and TBT degradation. Although pH 8.9 was more suitable for C. demersum L. growth, it uptook and metabolized more TBT at pH 5.0, which may be because the cationic species TBT+ (at pH 5.0) was metabolized more easily than the neutral hydroxide species TBTOH (at pH 8.9). C. demersum L. may thus be the plant with the most potential for the remediation of OTC-contaminated freshwater environments.


Assuntos
Magnoliopsida/metabolismo , Compostos Orgânicos de Estanho/metabolismo , Poluentes Químicos da Água/metabolismo , Ecossistema , Água Doce , Compostos de Trialquitina , Poluentes Químicos da Água/análise
5.
Ecotoxicol Environ Saf ; 192: 110289, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061990

RESUMO

Comparatively limited knowledge is known about the accumulation processes of tributyltin (TBT) and triphenyltin (TPT) in fish and aquatic plant in the freshwater environment, which has hindered a full understanding of their bioaccumulation potential and ecological risks. In the present study, sorption of TBT and TPT on dead biota of both carp and C. demersum from water via the batch equilibrium technique as well as uptake of them on live biota of both carp and C. demersum from water at a static and a dynamic kinetics tests were investigated, respectively. Both TBT and TPT exhibit a high affinity in carps and C. demersum. And C. demersum has a faster metabolism either for TBT or TPT than carp. The apparent uptake values (Cbio = 1904-8831 µg/kg) or bioconcentration factor (BCF = 3333-44000 L/kg) were one or two orders of magnitude higher than that of estimated by a simple sorption (405-472 µg/kg) or lipid model (74.5-149.6 µg/kg) for carp, indicating the uptake of TBT and TPT did not only depend on lipids but also oxygen ligands or macromolecules such as amino acids and proteins of the living organism. In contrast, the apparent Cbio values (149.1-926.4 µg/kg) of both TBT and TPT were lower than that of estimated by sorption model (1341-1902 µg/kg) for C. demersum, which were due to the rapid metabolic rate of them, especially for TBT. But no relation was observed between TBT and TPT concentrations and lipid contents in C. demersum.


Assuntos
Compostos Orgânicos de Estanho/farmacocinética , Compostos de Trialquitina/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Carpas/metabolismo , Cinética , Magnoliopsida/metabolismo
6.
Proc Natl Acad Sci U S A ; 117(9): 5059-5066, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32041869

RESUMO

The radiation of angiosperms led to the emergence of the vast majority of today's plant species and all our major food crops. Their extraordinary diversification occurred in conjunction with the evolution of a more efficient vascular system for the transport of water, composed of vessel elements. The physical dimensions of these water-conducting specialized cells have played a critical role in angiosperm evolution; they determine resistance to water flow, influence photosynthesis rate, and contribute to plant stature. However, the genetic factors that determine their dimensions are unclear. Here we show that a previously uncharacterized gene, ENLARGED VESSEL ELEMENT (EVE), contributes to the dimensions of vessel elements in Populus, impacting hydraulic conductivity. Our data suggest that EVE is localized in the plasma membrane and is involved in potassium uptake of differentiating xylem cells during vessel development. In plants, EVE first emerged in streptophyte algae, but expanded dramatically among vessel-containing angiosperms. The phylogeny, structure and composition of EVE indicates that it may have been involved in an ancient horizontal gene-transfer event.


Assuntos
Magnoliopsida/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Evolução Biológica , Membrana Celular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Fotossíntese , Phycodnaviridae , Plantas Geneticamente Modificadas , Potássio/metabolismo , Água/metabolismo , Xilema/citologia , Xilema/metabolismo
7.
Planta ; 251(3): 67, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32072272

RESUMO

MAIN CONCLUSION: Volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda, suggesting a defensive and attractive double role of these compounds. Flower volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda. A mixture of seven volatile compounds is found in flower buds, with limonene resulting as the most abundant compound (67%). Further five volatiles are found in freshly opened flowers, with limonene contributing to 31.7%, followed by decanal (15.5%) and by ethyl octanoate (10.3%). While monoterpene hydrocarbons dominate in flower buds (73.6%), their emission in freshly opened flowers is reduced to 41.1%, while non-terpene derivatives are the most abundant (47.1%) chemical class. These compounds, emitted in low amounts, are possibly linked to pollen, which is considered the only reward offered for insect-pollination in this species.


Assuntos
Flores/metabolismo , Magnoliopsida/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Compostos Fitoquímicos/metabolismo
8.
Chemosphere ; 246: 125816, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918109

RESUMO

Washing is one of the techniques for permanent removal of heavy metals from industrial sludge, for which washing agents are a key influence factor. However, high-efficiency, eco-friendly, and inexpensive agents are still lacking. In this study, the solutions derived from the three plant materials including Fatsia japonica, Hovenia acerba and Pterocarya stenoptera were employed to remove Cd, Cu, Pb, and Ni from industrial sludge. The effects of washing solution concentration, pH, washing time and temperature on metal removal were investigated. The metal removal efficiencies were found to increase with increasing solution concentrations or washing temperatures, decline with increasing pH, and presented various trends with increasing washing time. Among the three agents that derived from H. acerba showed relatively high removal for Cu (75.81%), Pb (63.42%), Ni (27.52%), and Cd (56.99%). After washing, environmental risks of residual metals were markedly diminished in sludge, attributable to decrease in their exchangeable forms. Furthermore, the applications of the plant washing agents increased sludge organic carbon, alkali-hydrolysable nitrogen, available phosphorus, and available potassium. Fourier transform infrared spectroscopy analysis suggested that the hydroxyl, carboxyl, ether, and amide may be the main functional groups in the three plant materials binding the heavy metals. Overall, the agent derived from H. acerba appears to be a feasible washing material for heavy metals removal from sludge.


Assuntos
Metais Pesados/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Magnoliopsida/metabolismo , Metais Pesados/análise , Esgotos/química , Poluentes do Solo/análise , Poluentes Químicos da Água/análise
9.
BMC Genomics ; 21(1): 49, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941462

RESUMO

BACKGROUND: Clinopodium gracile (Benth.) Matsum (C. gracile) is an annual herb with pharmacological properties effective in the treatment of various diseases, including hepatic carcinoma. Triterpenoid saponins are crucial bioactive compounds in C. gracile. However, the molecular understanding of the triterpenoid saponin biosynthesis pathway remains unclear. RESULTS: In this study, we performed RNA sequencing (RNA-Seq) analysis of the flowers, leaves, roots, and stems of C. gracile plants using the BGISEQ-500 platform. The assembly of transcripts from all four types of tissues generated 128,856 unigenes, of which 99,020 were mapped to several public databases for functional annotation. Differentially expressed genes (DEGs) were identified via the comparison of gene expression levels between leaves and other tissues (flowers, roots, and stems). Multiple genes encoding pivotal enzymes, such as squalene synthase (SS), or transcription factors (TFs) related to triterpenoid saponin biosynthesis were identified and further analyzed. The expression levels of unigenes encoding important enzymes were verified by quantitative real-time PCR (qRT-PCR). Different chemical constituents of triterpenoid saponins were identified by Ultra-Performance Liquid Chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS). CONCLUSIONS: Our results greatly extend the public transcriptome dataset of C. gracile and provide valuable information for the identification of candidate genes involved in the biosynthesis of triterpenoid saponins and other important secondary metabolites.


Assuntos
Magnoliopsida/genética , Saponinas/biossíntese , Transcriptoma , Triterpenos/metabolismo , Vias Biossintéticas/genética , Farnesil-Difosfato Farnesiltransferase/química , Magnoliopsida/enzimologia , Magnoliopsida/metabolismo , RNA-Seq , Reação em Cadeia da Polimerase em Tempo Real , Saponinas/química , Metabolismo Secundário/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triterpenos/química
10.
Ecotoxicol Environ Saf ; 189: 110049, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812820

RESUMO

Ceratophyllum demersum is a submerged aquatic angiosperm which is fast growing in contaminated water. This plant has no roots and so takes up nutrients from the water column without the complicating factor of differential shoot/root uptake of nutrients. This study aimed to compare the bioaccumulative capacities of Cu, Zn and their combination by C. demersum and physiological responses (growth, chlorophyll content, and photosynthetic rate) of C. demersum to Cu and Zn. Additionally, pulse amplitude modulation (PAM) technology and integrating sphere spectrometer were applied to detect copper and zinc toxicity effects on the light reactions of photosynthesis C. demersum is an aquatic plant that could be a good accumulator of Cu and Zn in actual solution in the water column. Additionally, RGR (relative growth rate) and chlorophyll content of C. demersum show that toxic effects of Cu or Zn increased over time. Cu and Zn effects manifested themselves more slowly than expected: at least 5 to 10 d were needed for noticeable effects both macroscopically (physical appearance), biochemical (chlorophyll content) and from measurements of photosynthesis using Pulse Amplitude Modulation (PAM) fluorometry. Moreover, the combination of Cu and Zn caused more toxic effect than either Cu or Zn separately. Whole plant scans using an integrating sphere spectrophotometer showed that Cu, Zn and Zn + Cu toxicity effects could be identified from spectral scans but were not specific enough for Cu, Zn and Zn + Cu toxicity to be distinguished from one another.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Bioacumulação , Cobre/toxicidade , Magnoliopsida/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Organismos Aquáticos/metabolismo , Clorofila/metabolismo , Cobre/metabolismo , Água Doce/química , Magnoliopsida/metabolismo , Fotossíntese/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Zinco/metabolismo
11.
J Ethnopharmacol ; 246: 112158, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31421182

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sri Lanka is known to have very diverse flora. Many of these species are used for plant-based remedies, which form the integral part of two Sri Lankan systems of traditional medicine, Ayurveda and Deshiya Chikitsa. Despite their widespread use, only a limited number of studies have probed into the scientific evidence for bioactivity of these medicinal plants. Such studies rarely progress to the identification of bioactive natural products. AIM OF THE STUDY: The primary aim was to develop a bioactivity screening method and apply it to 50 Sri Lankan medicinal plants where antimicrobial properties could be relevant for its traditional use. The subsequent aim was the progression into defining and characterising potent isolates within targeted compound classes from such plants, i.e. Derris scandens and its antimicrobial flavonoids. MATERIAL AND METHODS: The plant collection comprised 24 species of Fabaceae, 15 Rubiaceae, 7 Solanaceae and 4 Cucurbitaceae plants. These 50 species were collected based on their ethnopharmacological importance and use in Sri Lankan traditional medicine. Crude extracts from each species were initially subjected to radial disc diffusion and microdilution assays. Subsequently, aqueous extracts of all plants were microfractionated in deep well plates using reversed-phase HPLC. Fractions were tested for antibacterial and cytotoxic activities and masses of target bioactive compounds were identified using mass spectrometry. Bioactive compounds with the masses identified through microfractions were isolated from Derris scandens using reversed-phase HPLC. The isolated pure compounds were characterised using LC-MS and NMR. RESULTS: Crude aqueous extracts from 19 species showed activity against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) in the radial disc diffusion assay. Crude aqueous extracts from 34 plant species and organic extracts from 46 plant species were active against S. aureus (≤4 mg mL-1) in the microdilution assay. Microfractionation demonstrated antibacterial activity for 19 plants and cytotoxicity for 6 plants. Furthermore, target bioactive compounds and their molecular ions were identified during microfractionation. Dalpanitin and vicenin-3, two of the flavonoids isolated from Derris scandens gave MICs of 23 µg mL-1 against S. aureus. Dalpanitin also exhibited relevant MICs on Gram-negative bacteria (94 µg mL-1 against Escherichia coli and Pseudomonas aeruginosa). CONCLUSION: The microfractionation protocol developed in this study enabled time-efficient screening of many plants species, using a small quantity of sample material. In addition, microfractionation served as a guiding tool for identifying individual antimicrobial compounds. Through this process, flavonoids were isolated from Derris scandens, out of which dalpanitin and vicenin-3 showed activity in the low micromolar range. The high hit rate for in vitro antibacterial properties from this ethnopharmacologically guided sample collection gives credence to Sri Lankan traditional herbal medicine as a source for drug discovery.


Assuntos
Antibacterianos/isolamento & purificação , Flavonoides/isolamento & purificação , Magnoliopsida/metabolismo , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Flavonoides/farmacologia , Humanos , Extratos Vegetais/química , Plantas Medicinais/metabolismo , Metabolismo Secundário , Sri Lanka
12.
Planta ; 251(1): 17, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776668

RESUMO

MAIN CONCLUSIONS: Using 227 dicotyledonous species in temperate region, we found the relationships among densities of different-order veins, creating diversity of leaf vascular architectures. Dicotyledonous angiosperms commonly possess a hierarchical leaf vascular system, wherein veins of different orders have different functions. Minor vein spacing determines leaf hydraulic efficiency, whereas the major veins provide mechanical support. However, there is limited information on the coordination between these vein orders across species, limiting our understanding of how diversity in vein architecture is arrayed. We aimed to examine the (1) relationships between vein densities at two spatial scales (lower- vs. higher-order veins and among minor veins) and (2) relationships of vein densities with plant functional traits. We studied ten traits related to vein densities and three functional traits (leaf dry mass per area [LMA], leaf longevity [LL], and adult plant height [Hadult]) for 227 phylogenetically diverse plant species that occur in temperate regions and examined the vein-vein and vein-functional traits relationships across species. The densities of lower- and higher-order veins were positively correlated across species. The minor vein density was positively correlated with the densities of both areoles and free-ending veins, and vascular networks with higher minor vein density tended to have a lower ratio of free-ending veins to areoles across species. Neither densities of lower- nor higher-order veins were related to LMA and LL. On the other hand, the densities of veins and areoles tended to be positively correlated with Hadult. These results suggest that densities of different-order veins are developmentally coordinated across dicotyledonous angiosperms and form the independent axis in resource use strategies based on the leaf economics spectrum.


Assuntos
Magnoliopsida/fisiologia , Folhas de Planta/fisiologia , Magnoliopsida/metabolismo , Filogenia , Folhas de Planta/metabolismo , Transpiração Vegetal/fisiologia
13.
Science ; 366(6467): 878-881, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31727836

RESUMO

Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.


Assuntos
Adaptação Fisiológica , Organismos Aquáticos/metabolismo , Bicarbonatos/metabolismo , Lagos , Magnoliopsida/metabolismo , Fotossíntese , Rios , Dióxido de Carbono/metabolismo
14.
Molecules ; 24(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652707

RESUMO

Although the evolutionary significance of the early-diverging flowering plant Amborella (Amborella trichopoda Baill.) is widely recognized, its metabolic landscape, particularly specialized metabolites, is currently underexplored. In this work, we analyzed the metabolomes of Amborella tissues using liquid chromatography high-resolution electrospray ionization mass spectrometry (LC-HR-ESI-MS). By matching the mass spectra of Amborella metabolites with those of authentic phytochemical standards in the publicly accessible libraries, 63, 39, and 21 compounds were tentatively identified in leaves, stems, and roots, respectively. Free amino acids, organic acids, simple sugars, cofactors, as well as abundant glycosylated and/or methylated phenolic specialized metabolites were observed in Amborella leaves. Diverse metabolites were also detected in stems and roots, including those that were not identified in leaves. To understand the biosynthesis of specialized metabolites with glycosyl and methyl modifications, families of small molecule UDP-dependent glycosyltransferases (UGTs) and O-methyltransferases (OMTs) were identified in the Amborella genome and the InterPro database based on conserved functional domains. Of the 17 phylogenetic groups of plant UGTs (A-Q) defined to date, Amborella UGTs are absent from groups B, N, and P, but they are highly abundant in group L. Among the 25 Amborella OMTs, 7 cluster with caffeoyl-coenzyme A (CCoA) OMTs involved in lignin and phenolic metabolism, whereas 18 form a clade with plant OMTs that methylate hydroxycinnamic acids, flavonoids, or alkaloids. Overall, this first report of metabolomes and candidate metabolic genes in Amborella provides a starting point to a better understanding of specialized metabolites and biosynthetic enzymes in this basal lineage of flowering plants.


Assuntos
Evolução Molecular , Magnoliopsida , Filogenia , Compostos Fitoquímicos , Magnoliopsida/química , Magnoliopsida/genética , Magnoliopsida/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Análise de Sequência de DNA
15.
Environ Pollut ; 254(Pt B): 113101, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472457

RESUMO

As a floating plant, Myriophyllum aquaticum provides a large surface area under water, and thus has high potential for the removal of pollutants through adsorption. The aim of this study was to evaluate the potential adsorption of tetracycline (TC) by M. aquaticum, and examine the underlying mechanisms. M. aquaticum exhibited a high potential for TC removal from water. Adsorption was the main mechanism for rapid TC removal by live M. aquaticum plants, due to its large contact area and ion exchange, accounting for about 99% and 54% of the total amount of TC removed within 2 h and 5 d, respectively. Further, the roots of M. aquaticum exhibited a higher adsorption capacity than the stems or leaves, as the roots had the largest specific surface area. Fourier transform infrared spectroscopy analysis and identification of functional groups showed that -OH, -COOH, and -NH2 groups are involved in the adsorption process. The use of M. aquaticum may be a promising approach for TC removal from aquatic environments, especially in terms of shortening reaction times.


Assuntos
Magnoliopsida/química , Tetraciclina/química , Poluentes Químicos da Água/química , Adsorção , Troca Iônica , Magnoliopsida/metabolismo , Raízes de Plantas/química , Tetraciclina/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
16.
Plant Sci ; 287: 110177, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481209

RESUMO

The control of epidermal cell fate is an elaborate molecular process mediated by the TTG1-bHLH-MYB regulatory complex. In this study, we isolated PaMYB82 from London plane. PaMYB82 was revealed to be a nuclear-localized transcription activator and was found to be expressed ubiquitously in the tissues of roots, stems, leaves, cotyledons and hypocotyls. Expression of the PaMYB82 gene under the control of the viral CaMV35S promoter caused a nearly glabrous phenotype in wild type Arabidopsis and can partially rescue the gl1 mutant phenotype. Protein interaction analysis revealed that PaMYB82 physically interacts with PaGL3 and itself, in addition, PaMYB82 could interact with trichome related bHLH transcription factors AtGL3, AtEGL3 and AtMYC1. Expression levels of AtGL2, AtTTG2 and several R3 MYB genes were greatly increased in 35S::PaMYB82 lines. The expression of AtMYB23 was reduced in 35S::PaMYB82 transgenic lines, whereas, expression levels of AtGL1 remained unchanged indicating that differences in the transcriptional regulation of AtMYB23 and AtGL1 during trichome development. Together, the data presented here indicate that PaMYB82 encodes a functional R2R3 MYB transcription factor which can control the initiation of Arabidopsis trichome development.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Tricomas/crescimento & desenvolvimento , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Magnoliopsida/genética , Magnoliopsida/fisiologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
17.
BMC Biol ; 17(1): 70, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488154

RESUMO

BACKGROUND: Strigolactones (SLs) are an important class of carotenoid-derived signalling molecule in plants, which function both as exogenous signals in the rhizosphere and as endogenous plant hormones. In flowering plants, SLs are synthesized by a core pathway of four enzymes and are perceived by the DWARF14 (D14) receptor, leading to degradation of SMAX1-LIKE7 (SMXL7) target proteins in a manner dependent on the SCFMAX2 ubiquitin ligase. The evolutionary history of SLs is poorly understood, and it is not clear whether SL synthesis and signalling are present in all land plant lineages, nor when these traits evolved. RESULTS: We have utilized recently-generated genomic and transcriptomic sequences from across the land plant clade to resolve the origin of each known component of SL synthesis and signalling. We show that all enzymes in the core SL synthesis pathway originated at or before the base of land plants, consistent with the previously observed distribution of SLs themselves in land plant lineages. We also show that the late-acting enzyme LATERAL BRANCHING OXIDOREDUCTASE (LBO) may be considerably more ancient than previously thought. We perform a detailed phylogenetic analysis of SMXL proteins and show that specific SL target proteins only arose in flowering plants. We also assess diversity and protein structure in the SMXL family, identifying several previously unknown clades. CONCLUSIONS: Overall, our results suggest that SL synthesis is much more ancient than canonical SL signalling, consistent with the idea that SLs first evolved as rhizosphere signals and were only recruited much later as hormonal signals.


Assuntos
Embriófitas , Lactonas/metabolismo , Magnoliopsida , Reguladores de Crescimento de Planta , Proteínas de Plantas/genética , Embriófitas/classificação , Embriófitas/genética , Embriófitas/metabolismo , Evolução Molecular , Magnoliopsida/classificação , Magnoliopsida/genética , Magnoliopsida/metabolismo , Filogenia , Reguladores de Crescimento de Planta/biossíntese , Reguladores de Crescimento de Planta/metabolismo
18.
Phytochemistry ; 167: 112097, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31445450

RESUMO

This work used Δ5-sterols and their degradation products to compare the efficiency of biotic and abiotic degradation processes in senescent Mediterranean marine (Posidonia oceanica) and terrestrial (Quercus ilex and Smilax aspera) angiosperms. Type II photosensitized oxidation processes appeared to be more efficient in P. oceanica than in Q. ilex and S. aspera. The low efficiency of these processes in senescent terrestrial angiosperms was attributed to: (i) the fast degradation of the sensitizer (chlorophyll) in these organisms and (ii) the relatively high on-ground temperatures observed in Mediterranean regions favoring the diffusion of singlet oxygen outside the membranes. Senescent leaves of P. oceanica contained the highest proportions of photochemically-produced 6-hydroperoxysterols, likely due to the presence of trace amounts of metal ions in seawater catalyzing selective homolytic cleavage of 5- and 7-hydroperoxysterols. Bacterial metabolites of sitosterol and its photooxidation products could be detected in senescent leaves of P. oceanica but not Q. ilex or S. aspera. These results confirmed that biotic and abiotic degradation processes may be intimately linked in the environment.


Assuntos
Magnoliopsida/metabolismo , Esteróis/metabolismo , Biomarcadores/química , Biomarcadores/metabolismo , Magnoliopsida/crescimento & desenvolvimento , Região do Mediterrâneo , Folhas de Planta/metabolismo , Esteróis/química
19.
Genome Biol Evol ; 11(8): 2292-2305, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364708

RESUMO

Gene duplicates, generated through either whole genome duplication (WGD) or small-scale duplication (SSD), are prominent in angiosperms and are believed to play an important role in adaptation and in generating evolutionary novelty. Previous studies reported contrasting evolutionary and functional dynamics of duplicate genes depending on the mechanism of origin, a behavior that is hypothesized to stem from constraints to maintain the relative dosage balance between the genes concerned and their interaction context. However, the mechanisms ultimately influencing loss and retention of gene duplicates over evolutionary time are not yet fully elucidated. Here, by using a robust classification of gene duplicates in Arabidopsis thaliana, Solanum lycopersicum, and Zea mays, large RNAseq expression compendia and an extensive protein-protein interaction (PPI) network from Arabidopsis, we investigated the impact of PPIs on the differential evolutionary and functional fate of WGD and SSD duplicates. In all three species, retained WGD duplicates show stronger constraints to diverge at the sequence and expression level than SSD ones, a pattern that is also observed for shared PPI partners between Arabidopsis duplicates. PPIs are preferentially distributed among WGD duplicates and specific functional categories. Furthermore, duplicates with PPIs tend to be under stronger constraints to evolve than their counterparts without PPIs regardless of their mechanism of origin. Our results support dosage balance constraint as a specific property of genes involved in biological interactions, including physical PPIs, and suggest that additional factors may be differently influencing the evolution of genes following duplication, depending on the species, time, and mechanism of origin.


Assuntos
Evolução Molecular , Duplicação Gênica , Genoma de Planta , Magnoliopsida/genética , Magnoliopsida/metabolismo , Proteínas de Plantas/genética , Mapas de Interação de Proteínas , Regulação da Expressão Gênica de Plantas , Transcriptoma
20.
Int J Mol Sci ; 20(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466291

RESUMO

Kinesin-12 family members are characterized by an N-terminal motor domain and the extensive presence of coiled-coil domains. Animal orthologs display microtubule plus-end directed motility, bundling of parallel and antiparallel microtubules, plus-end stabilization, and they play a crucial role in spindle assembly. In plants, kinesin-12 members mediate a number of developmental processes including male gametophyte, embryo, seedling, and seed development. At the cellular level, they participate in critical events during cell division. Several kinesin-12 members localize to the phragmoplast midzone, interact with isoforms of the conserved microtubule cross-linker MICROTUBULE-ASSOCIATED PROTEIN 65 (MAP65) family, and are required for phragmoplast stability and expansion, as well as for proper cell plate development. Throughout cell division, a subset of kinesin-12 reside, in addition or exclusively, at the cortical division zone and mediate the accurate guidance of the phragmoplast. This review aims to summarize the current knowledge on kinesin-12 in plants and shed some light onto the heterogeneous localization and domain architecture, which potentially conceals functional diversification.


Assuntos
Divisão Celular , Cinesina/genética , Proteínas de Plantas/genética , Cromossomos de Plantas/genética , Cinesina/metabolismo , Magnoliopsida/citologia , Magnoliopsida/genética , Magnoliopsida/metabolismo , Proteínas de Plantas/metabolismo
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