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1.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638789

RESUMO

Starch phosphorylase is a member of the GT35-glycogen-phosphorylase superfamily. Glycogen phosphorylases have been researched in animals thoroughly when compared to plants. Genetic evidence signifies the integral role of plastidial starch phosphorylase (PHO1) in starch biosynthesis in model plants. The counterpart of PHO1 is PHO2, which specifically resides in cytosol and is reported to lack L80 peptide in the middle region of proteins as seen in animal and maltodextrin forms of phosphorylases. The function of this extra peptide varies among species and ranges from the substrate of proteasomes to modulate the degradation of PHO1 in Solanum tuberosum to a non-significant effect on biochemical activity in Oryza sativa and Hordeum vulgare. Various regulatory functions, e.g., phosphorylation, protein-protein interactions, and redox modulation, have been reported to affect the starch phosphorylase functions in higher plants. This review outlines the current findings on the regulation of starch phosphorylase genes and proteins with their possible role in the starch biosynthesis pathway. We highlight the gaps in present studies and elaborate on the molecular mechanisms of phosphorylase in starch metabolism. Moreover, we explore the possible role of PHO1 in crop improvement.


Assuntos
Magnoliopsida/enzimologia , Plastídeos/enzimologia , Amido Fosforilase/metabolismo , Magnoliopsida/metabolismo , Amido/metabolismo
2.
PLoS One ; 16(9): e0257690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591865

RESUMO

Aucuba japonica Thunb. is an evergreen understory shrub that grows naturally at a mine site. The mine soil contains high concentrations of heavy metals, and A. japonica appears to maintain detoxification mechanisms against heavy metals in the study site's understory. This study aimed to investigate the heavy metal tolerance mechanisms in A. japonica, considering the possible roles of arbuscular mycorrhizal and root-endophytic fungi. We conducted fieldwork in summer (canopy-foliation season) and winter (canopy-defoliation season) to measure the heavy metal concentrations in leaves, branches, and roots and analyze possible detoxicants in the roots. The infection rates of arbuscular mycorrhizal and root-endophytic fungi were evaluated via microscopic observation, and heavy metal (Zn) localization in A. japonica roots was observed using confocal laser scanning microscopy. Field analysis showed that A. japonica accumulated excessive Zn and produced aucubin and citric acid in the roots in both summer and winter. Zn localization observations clarified that Zn was distributed in thickened epidermal and cortical cell walls, suggesting that the cell walls functioned as Zn deposition sites, reducing Zn toxicity. It was further clarified that Zn was contained within cortical cells, indicating that Zn might be detoxified by aucubin and citric acid. Arbuscular mycorrhizal and root-endophytic fungi within cortical cells adsorbed Zn on fungal cell walls, indicating that these fungi would reduce Zn content within root cells and might alleviate Zn toxicity. Our results indicated that A. japonica would maintain Zn tolerance in both summer and winter via Zn immobilization in the cell walls and production of aucubin and citric acid, and that arbuscular mycorrhizal and root-endophytic fungi might play important roles in the Zn tolerance of A. japonica.


Assuntos
Glucosídeos Iridoides/metabolismo , Magnoliopsida/crescimento & desenvolvimento , Metais Pesados/química , Zinco/química , Adsorção , Biodegradação Ambiental , Parede Celular/química , Ácido Cítrico/química , Japão , Magnoliopsida/metabolismo , Micélio/química , Fotossíntese
3.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361766

RESUMO

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography-gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 µg/mL and a scavenging capacity SC50 of 800 µg/mL.


Assuntos
Antibacterianos/química , Antioxidantes/química , Monoterpenos Cicloexânicos/química , Magnoliopsida/química , Óleos Voláteis/química , Derivados de Alilbenzenos/química , Derivados de Alilbenzenos/isolamento & purificação , Anisóis/química , Anisóis/isolamento & purificação , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Arthrodermataceae/efeitos dos fármacos , Arthrodermataceae/crescimento & desenvolvimento , Benzotiazóis/antagonistas & inibidores , Monoterpenos Bicíclicos/química , Monoterpenos Bicíclicos/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Monoterpenos Cicloexânicos/isolamento & purificação , Equador , Eugenol/análogos & derivados , Eugenol/química , Eugenol/isolamento & purificação , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Magnoliopsida/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Picratos/antagonistas & inibidores , Folhas de Planta/química , Plantas Medicinais , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Fatores Sexuais , Ácidos Sulfônicos/antagonistas & inibidores
4.
Nat Commun ; 12(1): 4941, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400639

RESUMO

Plant small RNAs are important regulatory elements that fine-tune gene expression and maintain genome integrity by silencing transposons. Reproductive organs of monocots produce abundant phased, small interfering RNAs (phasiRNAs). The 21-nt reproductive phasiRNAs triggered by miR2118 are highly enriched in pre-meiotic anthers, and have been found in multiple eudicot species, in contrast with prior reports of monocot specificity. The 24-nt reproductive phasiRNAs are triggered by miR2275, and are highly enriched during meiosis in many angiosperms. Here, we report the widespread presence of the 21-nt reproductive phasiRNA pathway in eudicots including canonical and non-canonical microRNA (miRNA) triggers of this pathway. In eudicots, these 21-nt phasiRNAs are enriched in pre-meiotic stages, a spatiotemporal distribution consistent with that of monocots and suggesting a role in anther development. Although this pathway is apparently absent in well-studied eudicot families including the Brassicaceae, Solanaceae and Fabaceae, our work in eudicots supports an earlier singular finding in spruce, a gymnosperm, indicating that the pathway of 21-nt reproductive phasiRNAs emerged in seed plants and was lost in some lineages.


Assuntos
Magnoliopsida/metabolismo , Nucleotídeos/metabolismo , RNA de Plantas/genética , RNA Interferente Pequeno/metabolismo , Sementes/metabolismo , Fragaria/genética , Fragaria/metabolismo , Regulação da Expressão Gênica de Plantas , Meiose , MicroRNAs/genética , Filogenia , Picea/genética , Proteínas de Plantas/genética , RNA de Cadeia Dupla/metabolismo , Solanaceae/metabolismo , Transcriptoma
5.
Int J Mol Sci ; 22(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34281238

RESUMO

This study evaluated the effects of different light spectra (white light; WL, blue light; BL and red light; RL) on the root morphological traits and metabolites accumulation and biosynthesis in Sarcandra glabra. We performed transcriptomic and metabolomic profiling by RNA-seq and ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), respectively. When morphological features were compared to WL, BL substantially increased under-ground fresh weight, root length, root surface area, and root volume, while RL inhibited these indices. A total of 433 metabolites were identified, of which 40, 18, and 68 compounds differentially accumulated in roots under WL (WG) vs. roots under BL (BG), WG vs. roots under RL (RG), and RG vs. BG, respectively. In addition, the contents of sinapyl alcohol, sinapic acid, fraxetin, and 6-methylcoumarin decreased significantly in BG and RG. In contrast, chlorogenic acid, rosmarinyl glucoside, quercitrin and quercetin were increased considerably in BG. Furthermore, the contents of eight terpenoids compounds significantly reduced in BG. Following transcriptomic profiling, several key genes related to biosynthesis of phenylpropanoid-derived and terpenoids metabolites were differentially expressed, such as caffeic acid 3-O-methyltransferase) (COMT), hydroxycinnamoyl-CoA shikimate hydroxycinnamoyl transferase (HCT), O-methyltransferase (OMT), and 1-deoxy-D-xylulose-5-phosphate synthetase (DXS). In summary, our findings showed that BL was suitable for growth and accumulation of bioactive metabolites in root tissue of S. glabra. Exposure to a higher ratio of BL might have the potential to improve the production and quality of S. glabra seedlings, but this needs to be confirmed further.


Assuntos
Cor , Magnoliopsida/efeitos da radiação , Raízes de Plantas/efeitos da radiação , Metabolismo Secundário/efeitos da radiação , Plântula/efeitos da radiação , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Terpenos/metabolismo
6.
Chem Biodivers ; 18(8): e2100299, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34086421

RESUMO

The article reports the chemical composition, antioxidant, six key enzymes inhibitory and antimicrobial activities of two solvent extracts (water and methanol) of leaves and stem bark of Uapaca togoensis. For chemical composition, methanol extract of stem bark exhibited significant higher total phenolic (129.86 mg GAE/g) and flavanol (10.44 mg CE/g) contents. Methanol extract of leaves and water extract of stem bark showed high flavonoids (20.94 mg RE/g) and phenolic acid (90.40 mg CAE/g) content, respectively. In addition, HPLC-ESI-TOF-MS analysis revealed that U. togoensis was rich in procyanidins. The methanol and water extracts of stem bark had overall superior antioxidant activity; however, only methanol extract of stem bark showed higher inhibition of cholinesterase (AChE: 2.57 mg GALAE/g; BChE: 4.69 mg GALAE/g), tyrosinase (69.53 mg KAE/g) and elastase (2.73 mmol CE/g). Potent metal chelating ability was showed by water extract of leaves (18.94 mg EDTAE/g), higher inhibition of amylase was detected for water extracts of leaves (0.94 mmol ACAE/g) and stem bark (0.92 mmol ACAE/g). The tested extracts have shown wide-spectrum antibacterial properties and these effects have shown to be more effective against Aspergillus ochraceus, Penicillium funiculosum, Trichoderma viride, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The results revealed that the antioxidant, enzyme inhibitory and antimicrobial activities depended on the extraction solvents and the parts of plant. Bioinformatics analysis on the 17 major compounds showed modulation of pathway associated with cancer. In brief, U. togoensis might be valuable as potential source of natural agents for therapeutic application.


Assuntos
Biflavonoides/química , Catequina/química , Biologia Computacional/métodos , Inibidores Enzimáticos/química , Magnoliopsida/química , Extratos Vegetais/química , Proantocianidinas/química , Amilases/antagonistas & inibidores , Amilases/metabolismo , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/química , Biflavonoides/isolamento & purificação , Biflavonoides/metabolismo , Biflavonoides/farmacologia , Catequina/isolamento & purificação , Catequina/metabolismo , Catequina/farmacologia , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Magnoliopsida/metabolismo , Testes de Sensibilidade Microbiana , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Casca de Planta/química , Casca de Planta/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proantocianidinas/isolamento & purificação , Proantocianidinas/metabolismo , Proantocianidinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray
7.
Sci Rep ; 11(1): 12878, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145354

RESUMO

Nitraria sibirica Pall., a typical halophyte that can survive under extreme drought conditions and in saline-alkali environments, exhibits strong salt tolerance and environmental adaptability. Understanding the mechanism of molecular and physiological metabolic response to salt stress of plant will better promote the cultivation and use of halophytes. To explore the mechanism of molecular and physiological metabolic of N. sibirica response to salt stress, two-month-old seedlings were treated with 0, 100, and 400 mM NaCl. The results showed that the differentially expressed genes between 100 and 400 mmol L-1 NaCl and unsalted treatment showed significant enrichment in GO terms such as binding, cell wall, extemal encapsulating structure, extracellular region and nucleotide binding. KEGG enrichment analysis found that NaCl treatment had a significant effect on the metabolic pathways in N. sibirica leaves, which mainly including plant-pathogen interaction, amino acid metabolism of the beta alanine, arginine, proline and glycine metabolism, carbon metabolism of glycolysis, gluconeogenesis, galactose, starch and sucrose metabolism, plant hormone signal transduction and spliceosome. Metabolomics analysis found that the differential metabolites between the unsalted treatment and the NaCl treatment are mainly amino acids (proline, aspartic acid, methionine, etc.), organic acids (oxaloacetic acid, fumaric acid, nicotinic acid, etc.) and polyhydric alcohols (inositol, ribitol, etc.), etc. KEGG annotation and enrichment analysis showed that 100 mmol L-1 NaCl treatment had a greater effect on the sulfur metabolism, cysteine and methionine metabolism in N. sibirica leaves, while various amino acid metabolism, TCA cycle, photosynthetic carbon fixation and sulfur metabolism and other metabolic pathways have been significantly affected by 400 mmol L-1 NaCl treatment. Correlation analysis of differential genes in transcriptome and differential metabolites in metabolome have found that the genes of AMY2, BAM1, GPAT3, ASP1, CML38 and RPL4 and the metabolites of L-cysteine, proline, 4-aminobutyric acid and oxaloacetate played an important role in N. sibirica salt tolerance control. This is a further improvement of the salt tolerance mechanism of N. sibirica, and it will provide a theoretical basis and technical support for treatment of saline-alkali soil and the cultivation of halophytes.


Assuntos
Perfilação da Expressão Gênica , Magnoliopsida/genética , Magnoliopsida/metabolismo , Metaboloma , Metabolômica , Estresse Salino , Transcriptoma , Biologia Computacional/métodos , Metabolismo Energético , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Redes Reguladoras de Genes , Redes e Vias Metabólicas , Metabolômica/métodos , Tolerância ao Sal
8.
Sci Rep ; 11(1): 11205, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045605

RESUMO

Endophytic fungi with the ability to produce plant based secondary metabolites are a potential alternative for producing the host plant metabolite and to prevent natural plants from extinction. To isolate a high metabolite yielding endophytic strain from plants, hundreds of endophytic strains are screened and tested for product yield separately under axenic state, before shortlisting the potential endophyte, which involves huge time consumption. In this study, strategies for screening and selection of high camptothecin yielding endophytes from their natural habitat were proposed. A correlation was built between the camptothecin yield in the explants and the endophytes isolated from them. In addition, camptothecin yield was compared between the endophytes isolated from young and matured plants. Further, camptothecin producers and non-producers strains were compared for their tolerance toward camptothecin. The study indicates that high camptothecin yielding endophytes were isolated from high yielding explants and younger plants and they were more tolerant to camptothecin in comparison to non-camptothecin yielding endophytes. Thus, choosing a young and high yielding explant for endophyte isolation, and use of camptothecin as a selective agent in the growth medium, can be instrumental in screening and selection of high camptothecin yielding endophytes from nature in relatively less time.


Assuntos
Camptotecina/metabolismo , Endófitos/metabolismo , Magnoliopsida/metabolismo
9.
FEBS Lett ; 595(12): 1734-1747, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33950520

RESUMO

The noncoding regions throughout the genome are in large part comprised of transposable elements (TEs), some of which are functionalized with long intergenic noncoding RNAs (lincRNAs). DNA methylation is predominantly associated with TEs, but little is known about its contribution to the transcription of lincRNAs. Here, we examine the lincRNA profiles of DNA methylation-related mutants of five species, Arabidopsis, rice, tomato, maize, and mouse, to elucidate patterns in lincRNA regulation under altered DNA methylation status. Significant activation of lincRNAs was observed in the absence of CG DNA methylation rather than non-CG. Our study establishes a working model of the contribution of DNA methylation to regulation of the dynamic activity of lincRNA transcription.


Assuntos
Ilhas de CpG , Metilação de DNA/fisiologia , DNA de Plantas/metabolismo , Magnoliopsida/metabolismo , RNA Longo não Codificante/biossíntese , RNA de Plantas/biossíntese , Transcriptoma/fisiologia , Animais , DNA de Plantas/genética , Camundongos , RNA Longo não Codificante/genética , RNA de Plantas/genética , Especificidade da Espécie
10.
Trends Plant Sci ; 26(9): 898-912, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33893047

RESUMO

Oxygenic phototrophs use the Calvin-Benson cycle to fix CO2 during photosynthesis. In the dark, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), two enzymes of the Calvin-Benson cycle, form an inactive complex with the regulatory protein CP12, mainly under the control of thioredoxins and pyridine nucleotides. In the light, complex dissociation allows GAPDH and PRK reactivation. The GAPDH/CP12/PRK complex is conserved from cyanobacteria to angiosperms and coexists in land plants with an autoassembling GAPDH that is analogously regulated. With the recently described 3D structures of PRK and GAPDH/CP12/PRK, the structural proteome of this ubiquitous regulatory system has been completed. This outcome opens a new avenue for understanding the regulatory potential of photosynthetic carbon fixation by laying the foundation for its knowledge-based manipulation.


Assuntos
Cianobactérias , Magnoliopsida , Fotossíntese , Cianobactérias/genética , Cianobactérias/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Magnoliopsida/genética , Magnoliopsida/metabolismo , Tiorredoxinas/metabolismo
11.
Sci Rep ; 11(1): 7885, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846460

RESUMO

In the complex process of homeostasis of phytohormones cytokinins (CKs), O-glucosylation catalyzed by specific O-glucosyltransferases represents one of important mechanisms of their reversible inactivation. The CK O-glucosyltransferases belong to a highly divergent and polyphyletic multigene superfamily of glycosyltransferases, of which subfamily 1 containing UDP-glycosyltransferases (UGTs) is the largest in the plant kingdom. It contains recently discovered O and P subfamilies present in higher plant species but not in Arabidopsis thaliana. The cis-zeatin O-glucosyltransferase (cisZOG) genes belong to the O subfamily encoding a stereo-specific O-glucosylation of cis-zeatin-type CKs. We studied different homologous genes, their domains and motifs, and performed a phylogenetic reconstruction to elucidate the plant evolution of the cisZOG gene. We found that the cisZOG homologs do not form a clear separate clade, indicating that diversification of the cisZOG gene took place after the diversification of the main angiosperm families, probably within genera or closely related groups. We confirmed that the gene(s) from group O is(are) not present in A. thaliana and is(are) also missing in the family Brassicaceae. However, cisZOG or its metabolites are found among Brassicaceae clade, indicating that remaining genes from other groups (UGT73-group D and UGT85-group G) are able, at least in part, to substitute the function of group O lost during evolution. This study is the first detailed evolutionary evaluation of relationships among different plant ZOGs within angiosperms.


Assuntos
Brassicaceae/genética , Citocininas/genética , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/genética , Magnoliopsida , Proteínas de Plantas/genética , Magnoliopsida/genética , Magnoliopsida/metabolismo
12.
Int J Mol Sci ; 22(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925728

RESUMO

In angiosperms, the mature seed consists of embryo, endosperm, and a maternal plant-derived seed coat (SC). The SC plays a role in seed filling, protects the embryo, mediates dormancy and germination, and facilitates the dispersal of seeds. SC properties have been modified during the domestication process, resulting in the removal of dormancy, mediated by SC impermeability. This study compares the SC anatomy and histochemistry of two wild (JI64 and JI1794) and two domesticated (cv. Cameor and JI92) pea genotypes. Histochemical staining of five developmental stages: 13, 21, 27, 30 days after anthesis (DAA), and mature dry seeds revealed clear differences between both pea types. SC thickness is established early in the development (13 DAA) and is primarily governed by macrosclereid cells. Polyanionic staining by Ruthenium Red indicated non homogeneity of the SC, with a strong signal in the hilum, the micropyle, and the upper parts of the macrosclereids. High peroxidase activity was detected in both wild and cultivated genotypes and increased over the development peaking prior to desiccation. The detailed knowledge of SC anatomy is important for any molecular or biochemical studies, including gene expression and proteomic analysis, especially when comparing different genotypes and treatments. Analysis is useful for other crop-to-wild-progenitor comparisons of economically important legume crops.


Assuntos
Ervilhas/genética , Ervilhas/metabolismo , Sementes/genética , Domesticação , Endosperma , Genótipo , Germinação , Magnoliopsida/genética , Magnoliopsida/metabolismo , Proteômica , Sementes/metabolismo
13.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807566

RESUMO

Angiosperm reproduction relies on the precise growth of the pollen tube through different pistil tissues carrying two sperm cells into the ovules' embryo sac, where they fuse with the egg and the central cell to accomplish double fertilization and ultimately initiate seed development. A network of intrinsic and tightly regulated communication and signaling cascades, which mediate continuous interactions between the pollen tube and the sporophytic and gametophytic female tissues, ensures the fast and meticulous growth of pollen tubes along the pistil, until it reaches the ovule embryo sac. Most of the pollen tube growth occurs in a specialized tissue-the transmitting tract-connecting the stigma, the style, and the ovary. This tissue is composed of highly secretory cells responsible for producing an extensive extracellular matrix. This multifaceted matrix is proposed to support and provide nutrition and adhesion for pollen tube growth and guidance. Insights pertaining to the mechanisms that underlie these processes remain sparse due to the difficulty of accessing and manipulating the female sporophytic tissues enclosed in the pistil. Here, we summarize the current knowledge on this key step of reproduction in flowering plants with special emphasis on the female transmitting tract tissue.


Assuntos
Fertilização/fisiologia , Flores/fisiologia , Óvulo Vegetal/fisiologia , Matriz Extracelular/fisiologia , Flores/metabolismo , Magnoliopsida/metabolismo , Magnoliopsida/fisiologia , Óvulo Vegetal/metabolismo , Proteínas de Plantas/metabolismo , Tubo Polínico/metabolismo , Tubo Polínico/fisiologia , Sementes/metabolismo , Transdução de Sinais/fisiologia
14.
Int J Mol Sci ; 22(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923657

RESUMO

Mounting evidence from genomic and transcriptomic studies suggests that most genetic networks regulating the morphogenesis of land plant sporophytes were co-opted and modified from those already present in streptophyte algae and gametophytes of bryophytes sensu lato. However, thus far, no candidate genes have been identified that could be responsible for "planation", a conversion from a three-dimensional to a two-dimensional growth pattern. According to the telome theory, "planation" was required for the genesis of the leaf blade in the course of leaf evolution. The key transcription factors responsible for leaf blade development in angiosperms are YABBY proteins, which until recently were thought to be unique for seed plants. Yet, identification of a YABBY homologue in a green alga and the recent findings of YABBY homologues in lycophytes and hornworts suggest that YABBY proteins were already present in the last common ancestor of land plants. Thus, these transcriptional factors could have been involved in "planation", which fosters our understanding of the origin of leaves. Here, we summarise the current data on functions of YABBY proteins in the vegetative and reproductive development of diverse angiosperms and gymnosperms as well as in the development of lycophytes. Furthermore, we discuss a putative role of YABBY proteins in the genesis of multicellular shoot apical meristems and in the evolution of leaves in early divergent terrestrial plants.


Assuntos
Evolução Molecular , Magnoliopsida/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
15.
Int J Mol Sci ; 22(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918442

RESUMO

While human extracellular vesicles (EVs) have attracted a big deal of interest and have been extensively characterized over the last years, plant-derived EVs and nanovesicles have earned less attention and have remained poorly investigated. Although a series of investigations already revealed promising beneficial health effects and drug delivery properties, adequate (pre)clinical studies are rare. This fact might be caused by a lack of sources with appropriate qualities. Our study introduces plant cell suspension culture as a new and well controllable source for plant EVs. Plant cells, cultured in vitro, release EVs into the growth medium which could be harvested for pharmaceutical applications. In this investigation we characterized EVs and nanovesicles from distinct sources. Our findings regarding secondary metabolites indicate that these might not be packaged into EVs in an active manner but enriched in the membrane when lipophilic enough, since apparently lipophilic compounds were associated with nanovesicles while more hydrophilic structures were not consistently found. In addition, protein identification revealed a possible explanation for the mechanism of EV cell wall passage in plants, since cell wall hydrolases like 1,3-ß-glucosidases, pectinesterases, polygalacturonases, ß-galactosidases and ß-xylosidase/α-L-arabinofuranosidase 2-like are present in plant EVs and nanovesicles which might facilitate cell wall transition. Further on, the identified proteins indicate that plant cells secrete EVs using similar mechanisms as animal cells to release exosomes and microvesicles.


Assuntos
Vesículas Extracelulares/ultraestrutura , Magnoliopsida/metabolismo , Metabolismo Secundário , Técnicas de Cultura de Células , Células Cultivadas , Craterostigma , Fosfolipídeos/metabolismo , Proteoma
16.
BMC Genomics ; 22(1): 252, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33836656

RESUMO

BACKGROUND: Plant transitions to land require robust cell walls for regulatory adaptations and to resist changing environments. Cell walls provide essential plasticity for plant cell division and defense, which are often conferred by the expansin superfamily with cell wall-loosening functions. However, the evolutionary mechanisms of expansin during plant terrestrialization are unclear. RESULTS: Here, we identified 323 expansin proteins in 12 genomes from algae to angiosperms. Phylogenetic evolutionary, structural, motif gain and loss and Ka/Ks analyses indicated that highly conserved expansin proteins were already present in algae and expanded and purified after plant terrestrialization. We found that the expansion of the FtEXPA subfamily was caused by duplication events and that the functions of certain duplicated genes may have differentiated. More importantly, we generated space-time expression profiles and finally identified five differentially expressed FtEXPs in both large and small fruit Tartary buckwheat that may regulate fruit size by responding to indoleacetic acid. CONCLUSIONS: A total of 323 expansin proteins from 12 representative plants were identified in our study during terrestrialization, and the expansin family that originated from algae expanded rapidly after the plants landed. The EXPA subfamily has more members and conservative evolution in angiosperms. FtEXPA1, FtEXPA11, FtEXPA12, FtEXPA19 and FtEXPA24 can respond to indole-3-acetic acid (IAA) signals and regulate fruit development. Our study provides a blueprint for improving the agronomic traits of Tartary buckwheat and a reference for defining the evolutionary history of the expansin family during plant transitions to land.


Assuntos
Fagopyrum , Magnoliopsida , Fagopyrum/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Magnoliopsida/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
17.
J Plant Physiol ; 258-259: 153391, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33647786

RESUMO

The male gametophyte of angiosperms has long been recognized as an ideal system for the study of the molecular mechanisms regulating cell fate determination. Recent findings on histone variants in two cell lineages, vegetative-cell-derived small interfering RNA and transposable element expression provide new power for relevant investigations.


Assuntos
Comunicação Celular/fisiologia , Epigênese Genética/fisiologia , Magnoliopsida/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Magnoliopsida/citologia , Magnoliopsida/metabolismo , Pólen/citologia , Pólen/metabolismo
18.
Plant Physiol ; 185(2): 478-490, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33721907

RESUMO

The architecture of the seed is shaped by the processes of tissue partitioning, which determines the volume ratio of maternal and zygotic tissues, and nutrient partitioning, which regulates nutrient distribution among tissues. In angiosperms, early seed development is characterized by antagonistic development of the nucellus maternal tissue and the endosperm fertilization product to become the main sugar sink. This process marked the evolution of angiosperms and outlines the most ancient seed architectures. In Arabidopsis, the endosperm partially eliminates the nucellus and imports sugars from the seed coat. Here, we show that the nucellus is symplasmically connected to the chalaza, the seed nutrient unloading zone, and works as both a sugar sink and source alongside the seed coat. After fertilization, the transient nucellus accumulates starch early on and releases it in the apoplasmic space during its elimination. By contrast, the persistent nucellus exports sugars toward the endosperm through the SWEET4 hexose facilitator. Finally, we analyzed sugar metabolism and transport in the transparent testa 16 mutant, which fails to undergo nucellus cell elimination, which shed light on the coordination between tissue and nutrient partitioning. Overall, this study identifies a path of sugar transport in the Arabidopsis seed and describes a link between sugar redistribution and the nucellus cell-elimination program.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Magnoliopsida/embriologia , Proteínas de Transporte de Monossacarídeos/metabolismo , Açúcares/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transporte Biológico , Endosperma/embriologia , Endosperma/genética , Endosperma/metabolismo , Magnoliopsida/genética , Magnoliopsida/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Mutação , Sementes/embriologia , Sementes/genética , Sementes/metabolismo , Amido/metabolismo
19.
Food Chem ; 353: 129435, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714113

RESUMO

An anthocyanin-rich extract was obtained from Nitraria tangutorum Bobr. fruit, namely ANF, and its composition, antioxidant and neuroprotective effects were studied. Nine anthocyanins were identified from the ANF using UPLC-Triple-TOF/MS analysis, and cyanidin-3-[2''-(6'''-coumaroyl)-glucosyl]-glucoside (C3G) is the most abundant anthocyanin (87.06%). ANF exhibited high ferric reducing antioxidant power (FRAP) and ABTS radical scavenging activity. The online HPLC-DPPH screening revealed that C3G contributed the highest antioxidant capacity. ANF showed potential neuroprotective effects by relieving d-Galactose-induced memory deficits, reducing overexpression of receptor for advanced glycation end products (RAGE) and amyloid-beta42 (Aß42) in the hippocampus of rats. Besides, ANF could inhibit oxidative stress by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in the hippocampus, while elevating amounts of total superoxide dismutase (T-SOD) and glutathione (GSH) in the serum of rats. Thus, ANF has great potential in the development of food and health products related to antioxidant and neuroprotective effects.


Assuntos
Antocianinas/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Magnoliopsida/química , Fármacos Neuroprotetores/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Antocianinas/química , Antocianinas/isolamento & purificação , Antocianinas/farmacologia , Feminino , Frutas/química , Frutas/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Magnoliopsida/metabolismo , Malondialdeído/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Superóxido Dismutase/metabolismo
20.
PLoS Biol ; 19(3): e3001123, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33770073

RESUMO

The female gametophytes of angiosperms contain cells with distinct functions, such as those that enable reproduction via pollen tube attraction and fertilization. Although the female gametophyte undergoes unique developmental processes, such as several rounds of nuclear division without cell plate formation and final cellularization, it remains unknown when and how the cell fate is determined during development. Here, we visualized the living dynamics of female gametophyte development and performed transcriptome analysis of individual cell types to assess the cell fate specifications in Arabidopsis thaliana. We recorded time lapses of the nuclear dynamics and cell plate formation from the 1-nucleate stage to the 7-cell stage after cellularization using an in vitro ovule culture system. The movies showed that the nuclear division occurred along the micropylar-chalazal (distal-proximal) axis. During cellularization, the polar nuclei migrated while associating with the forming edge of the cell plate, and then, migrated toward each other to fuse linearly. We also tracked the gene expression dynamics and identified that the expression of MYB98pro::GFP-MYB98, a synergid-specific marker, was initiated just after cellularization in the synergid, egg, and central cells and was then restricted to the synergid cells. This indicated that cell fates are determined immediately after cellularization. Transcriptome analysis of the female gametophyte cells of the wild-type and myb98 mutant revealed that the myb98 synergid cells had egg cell-like gene expression profiles. Although in myb98, egg cell-specific gene expression was properly initiated in the egg cells only after cellularization, but subsequently expressed ectopically in one of the 2 synergid cells. These results, together with the various initiation timings of the egg cell-specific genes, suggest complex regulation of the individual gametophyte cells, such as cellularization-triggered fate initiation, MYB98-dependent fate maintenance, cell morphogenesis, and organelle positioning. Our system of live-cell imaging and cell type-specific gene expression analysis provides insights into the dynamics and mechanisms of cell fate specifications in the development of female gametophytes in plants.


Assuntos
Arabidopsis/metabolismo , Diferenciação Celular/genética , Óvulo Vegetal/metabolismo , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Magnoliopsida/metabolismo , Morfogênese , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Tubo Polínico/genética , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética
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