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1.
Plant Mol Biol ; 102(6): 589-602, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32026326

RESUMO

Leaf angle is a key factor in plant architecture and crop yield. Brassinosteroids (BRs) regulate many developmental processes, especially the leaf angle in monocots. However, the BR signalling pathway is complex and includes many unknown members. Here, we propose that Oryza sativa BRASSINOSTEROID-RESPONSIVE LEAF ANGLE REGULATOR 1 (OsBLR1) encodes a bHLH transcription factor, and positively regulates BR signalling to increase the leaf angle and grain length in rice (Oryza sativa L.). Lines overexpressing OsBLR1 (blr1-D and BLR1-OE-1/2/3) had similar traits, with increased leaf angle and grain length. Conversely, OsBLR1-knockout mutants (blr1-1/2/3) had erect leaves and shorter grains. Lamina joint inclination, coleoptile elongation, and root elongation assay results indicated that these overexpression lines were more sensitive to BR, while the knockout mutants were less sensitive. There was no significant difference in the endogenous BR contents of blr1-1/2 and wild-type plants. These results suggest that OsBLR1 is involved in BR signal transduction. The blr1-D mutant, with increased cell growth in the lamina joint and smaller leaf midrib, showed significant changes in gene expression related to the cell wall and leaf development compared with wild-type plants; furthermore, the cellulose and protopectin contents in blr1-D were reduced, which resulted in the increased leaf angle and bent leaves. As the potential downstream target gene of OsBLR1, the REGULATOR OF LEAF INCLINATION1 (OsRLI1) gene expression was up-regulated in OsBLR1-overexpression lines and down-regulated in OsBLR1-knockout mutants. Moreover, we screened OsRACK1A as an interaction protein of OsBLR1 using a yeast two-hybrid assay and glutathione-S-transferase pull-down.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Brassinosteroides/metabolismo , Oryza/genética , Oryza/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Transdução de Sinais , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Genes de Plantas , Oryza/crescimento & desenvolvimento , Fenótipo , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/citologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais/genética , Fatores de Transcrição
2.
Chemosphere ; 244: 125579, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050351

RESUMO

Although Solanum nigrum L. is a phytoremediator for different metals, its growth and physiology are still compromised by toxic levels of zinc (Zn). Thus, the development of eco-friendly strategies to enhance its tolerance, maintaining remediation potential is of special interest. This study evaluated the potential of 24-epibrassinolide (24-EBL) to boost S. nigrum defence against Zn towards a better growth rate and remediation potential. After 24 days of exposure, the results revealed that Zn-mediated inhibitory effects on biomass and biometry were efficiently mitigated upon application of 24-EBL, without affecting Zn accumulation. The evaluation of oxidative stress markers reported that Zn excess stimulated the accumulation of superoxide anion (O2.-), but reduced hydrogen peroxide (H2O2) levels, while not altering lipid peroxidation (LP). This was accompanied by an up-regulation of the antioxidant system, especially proline, superoxide dismutase (SOD) and ascorbate peroxidase (APX) in both organs, and ascorbate in roots of Zn-exposed plants. Foliar application of 24-EBL, however, induced distinctive effects, lowering proline levels in both organs, as well as APX activity in shoots and SOD in roots, whilst stimulating GSH and total thiols in both organs, as well as SOD and APX activity, in shoots and in roots, respectively. Probably due to a better antioxidant efficiency, levels of O2.- and H2O2 in pre-treated plants remained identical to the control, while LP further decreased in shoots. Overall, our results indicate a protective effect of 24-EBL on S. nigrum response to excess Zn, contributing for a better tolerance and growth rate, without disturbing its phytoremediation potential.


Assuntos
Brassinosteroides/metabolismo , Poluentes do Solo/toxicidade , Solanum nigrum/fisiologia , Esteroides Heterocíclicos/metabolismo , Zinco/toxicidade , Antioxidantes/farmacologia , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/farmacologia , Biodegradação Ambiental , Catalase/metabolismo , Peróxido de Hidrogênio/farmacologia , Peroxidação de Lipídeos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo , Zinco/análise
3.
Plant Mol Biol ; 103(1-2): 63-74, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32040757

RESUMO

KEY MESSAGE: PSBR1 is a moso bamboo gene negatively regulated by brassinosteroid, which encodes a mitochondrial localized protein. Overexpression of PSBR1 leads to growth inhibition in various growth progresses in Arabidopsis. The young shoot of moso bamboo (Phyllostachys edulis) is known as one of the fastest growing plant organs. The roles of phytohormones in the fast-growth of bamboo shoot are not fully understood. Brassinosteroids (BRs) are a group of growth-promoting steroid hormones that play important roles in cell elongation and division. While BR related genes are highly enriched in fast-growing internodes in moso bamboo, the functions of BR in the fast-growth process is not understood at the molecular level. Here, we identified a poaceae specific gene, PSBR1 (Poaceae specific and BR responsive gene 1) from the moso bamboo genome. PSBR1 was highly expressed in the stem and leaves of bamboo seedling, and the elongating nodes of fast-growing bamboo shoot. PSBR1's expression is increased by BR biosynthesis inhibitor propiconazole but decreased by BR treatment. PSBR1 encodes a novel protein that is localized to the mitochondria in tobacco and bamboo protoplast. The Arabidopsis transgenic plants overexpressing PSBR1 show growth inhibition in both vegetative and reproductive stages. This study suggests that PSBR1 is a BR regulated mitochondrial protein in bamboo, which inhibits plant growth when overexpressed in Arabidopsis.


Assuntos
Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Mitocondriais/genética , Proteínas de Plantas/genética , Poaceae/genética , Arabidopsis/genética , Reguladores de Crescimento de Planta/genética , Reguladores de Crescimento de Planta/metabolismo , Plantas Geneticamente Modificadas
4.
Plant Sci ; 291: 110315, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928681

RESUMO

Assuring fiber yield stability is the primary objective for cotton breeders since the world population is on the rise, and the demand for cotton fiber is increasing every year. Thus, enhancing average cotton boll weight (BWT) could improve seed cotton production, and ultimately to increase cotton fiber yield. This study accomplished the map-based cloning of a novel boll weight regulating locus, qBWT-c12, in cotton. Bulk segregation analysis detected linked markers, aided in the detection of a stable BWT regulating locus, qBWT-c12, on Chr12 in a novel boll size mutant, BS41. Progeny evaluation confined the qBWT-c12 to a 0.89 cM interval between the AD-A12_07 and AD-FM_44 markers in recombinant derived F3 and F4 populations. Homology mapping detected a 40 bp insertion-deletion (InDel) site in the AD-FM_44 clone sequence situated +341 downstream of GhBRH1_A12, which showed complete linkage to the BWT phenotype. The suppressed expression of GhBRH1_A12 suggested its putative involvement during early boll development events in BS41. Although brassinosteroid (BR) biosynthesis and signaling pathway genes were up regulated in different tissues, but the organ growth was suppressed leading to dwarf plants, smaller leaves, and de-morphed smaller bolls in BS41. Thus, a disruption in the BR signal cascade is anticipated and could be related to lower GhBRH1_A12 expression in BS41.This study firstly reported the genetic dissection of boll size regulation of G. barbadense in G. hirsutum background using map-based cloning of a BWT regulating locus, qBWT-c12. Moreover, it also emphasized the putative role GhBRH1_A12 in regulating BR homeostasis and its potential to modulate plant growth and boll development in cotton.


Assuntos
Brassinosteroides/metabolismo , Mapeamento Cromossômico , Loci Gênicos/fisiologia , Gossypium/fisiologia , Clonagem Molecular , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Tamanho do Órgão/genética
5.
PLoS One ; 15(1): e0219413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31899920

RESUMO

Seed dormancy and germination are the two important traits related to plant survival, reproduction and crop yield. To understand the regulatory mechanisms of these traits, it is crucial to clarify which genes or pathways participate in the regulation of these processes. However, little information is available on seed dormancy and germination in peanut. In this study, seeds of the variety Luhua No.14, which undergoes nondeep dormancy, were selected, and their transcriptional changes at three different developmental stages, the freshly harvested seed (FS), the after-ripening seed (DS) and the newly germinated seed (GS) stages, were investigated by comparative transcriptomic analysis. The results showed that genes with increased transcription in the DS vs FS comparison were overrepresented for oxidative phosphorylation, the glycolysis pathway and the tricarboxylic acid (TCA) cycle, suggesting that after a period of dry storage, the intermediates stored in the dry seeds were rapidly mobilized by glycolysis, the TCA cycle, the glyoxylate cycle, etc.; the electron transport chain accompanied by respiration was reactivated to provide ATP for the mobilization of other reserves and for seed germination. In the GS vs DS pairwise comparison, dozens of the upregulated genes were related to plant hormone biosynthesis and signal transduction, including the majority of components involved in the auxin signal pathway, brassinosteroid biosynthesis and signal transduction as well as some GA and ABA signal transduction genes. During seed germination, the expression of some EXPANSIN and XYLOGLUCAN ENDOTRANSGLYCOSYLASE genes was also significantly enhanced. To investigate the effects of different hormones during seed germination, the contents and differential distribution of ABA, GAs, BRs and IAA in the cotyledons, hypocotyls and radicles, and plumules of three seed sections at different developmental stages were also investigated. Combined with previous data in other species, it was suggested that the coordination of multiple hormone signal transduction nets plays a key role in radicle protrusion and seed germination.


Assuntos
Arachis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Germinação/genética , Proteínas de Plantas/genética , Sementes/genética , Transcriptoma , Ácido Abscísico/metabolismo , Trifosfato de Adenosina/biossíntese , Arachis/crescimento & desenvolvimento , Arachis/metabolismo , Brassinosteroides/metabolismo , Ciclo do Ácido Cítrico/genética , Ontologia Genética , Redes Reguladoras de Genes , Glicólise/genética , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Ácidos Indolacéticos/metabolismo , Anotação de Sequência Molecular , Fosforilação Oxidativa , Dormência de Plantas , Proteínas de Plantas/metabolismo , Característica Quantitativa Herdável , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Transdução de Sinais
6.
Mol Genet Genomics ; 295(2): 343-356, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31745640

RESUMO

Dwarfing is the development trend of pepper breeding. It is of great practical and scientific value to generate new dwarf germplasms, and identify new genes or alleles conferring dwarf traits in pepper. In our previous study, a weakly BR-insensitive dwarf mutant, E29, was obtained by EMS mutagenesis of the pepper inbred line 6421. It can be used as a good parent material for breeding new dwarf varieties. Here, we found that this dwarf phenotype was controlled by a single recessive gene. Whole-genome resequencing, dCAPs analysis, and VIGs validation revealed that this mutation was caused by a nonsynonymous single-nucleotide mutation (C to T) in CaBRI1. An enzyme activity assay, transcriptome sequencing, and BL content determination further revealed that an amino-acid change (Pro1157Ser) in the serine/threonine protein kinase and catalytic (S_TKc) domain of CaBRI1 impaired its kinase activity and caused the transcript levels of two important genes (CaDWF4 and CaROT3) participating in BR biosynthesis to increase dramatically in the E29 mutant, accompanied by significantly increased accumulation of brassinolide (BL). Therefore, we concluded that the novel single-base mutation in CaBRI1 conferred the dwarf phenotype and resulted in brassinosteroid (BR) accumulation in pepper. This study provides a new allelic variant of the height-regulating gene CaBRI1 that has theoretical and practical values for the breeding of the plants suitable for the facility cultivation and mechanized harvesting of pepper varieties.


Assuntos
Brassinosteroides/metabolismo , Capsicum/genética , Reguladores de Crescimento de Planta/genética , Proteínas de Plantas/genética , Alelos , Sequência de Aminoácidos/genética , Capsicum/metabolismo , Domínio Catalítico/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Mutagênese/genética , Mutação/genética , Oryza/genética , Proteínas Quinases/genética , Homologia de Sequência de Aminoácidos , Esteroides Heterocíclicos/metabolismo , Sequenciamento Completo do Genoma
7.
Plant Biol (Stuttg) ; 22(1): 129-133, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31469500

RESUMO

Heat shock proteins 90 (HSP90) are essential and play critical roles in the adaptation of organisms to diverse stimuli. In plants, HSP90 are involved in auxin, jasmonate and brassinosteroid (BR) signalling pathways. The BR-promoted activation of the BES1 transcription factor regulates BR-responsive genes. Using genetic, physiological, fluorescence live cell imaging, molecular and biochemical approaches, such as phenotypic analysis, co-immunoprecipitation assay, yeast-two hybrid and Bimolecular fluorescence complementation (BiFC), we studied complex formation between BES1 and HSP90 under control conditions and active BR signalling. Further, we determined the effect of the pharmacological inhibition of HSP90 ATPase activity on hypocotyl elongation of bes1-D mutant. We determined that HSP90 interact with BES1 in the nucleus and in the cytoplasm. During active BR signalling, nuclear complexes were absent while cytoplasmic HSP90/BES1 complexes were prominent. Our results showed that the hypocotyl length of bes1-D mutants was highly reduced when HSP90 was challenged by the geldanamycin (GDA) inhibitor of the ATPase activity of HSP90. Active BR signalling could not rescue the GDA effect on the hypocotyl elongation of bes1-D. Our results reveal that the constitutively active BES1 in the bes1-D mutant is hypersensitive to GDA. The interaction of HSP90 with BES1 argues that HSP90 facilitate the nuclear metastable conformation of BES1 to regulate BR-dependent gene expression, and our data show that HSP90 assist in the compartmentalised cycle of BES1 during active BR signalling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brassinosteroides , Proteínas de Choque Térmico HSP90 , Transdução de Sinais , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico HSP90/metabolismo , Tabaco/metabolismo
8.
J Plant Physiol ; 244: 153090, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31841952

RESUMO

The integral parts of the cell membranes are the functional proteins, which are crucial for cell life. Among them, proton-pumping ATPase and aquaporins appear to be of particular importance. There is some knowledge about the effect of the temperature during plant growth, including stress-inducing temperatures, on the accumulation of the membrane proteins: plasma membrane H+-ATPase and aquaporins, but not much is known about the effect of the phytohormones (i.e. brassinosteroids (BR)) on control of accumulation of these proteins. The aim of our study was to answer the question of how a BR deficit and disturbances in the BR perception/signalling affect the accumulation of plasma membrane H+-ATPase (PM H+-ATPase), the aquaporin HvPIP1 transcript and protein in barley growing at 20 °C and during its acclimation at 5 °C and 27 °C. For the studies, the BR-deficient mutant 522DK (derived from the wild-type Delisa), the BR-deficient mutant BW084 and the BR-signalling mutant BW312 and their wild-type Bowman were used. Generally, temperature of growth was significant factor influencing on the level of the accumulation of the H+-ATPase and HvPIP1 transcript and the PM H+-ATPase and HvPIP1 protein in barley leaves. The level of the accumulation of the HvPIP1 transcript decreased at 5 °C (compared to 20 °C), but was higher at 27 °C than at 20 °C in the analyzed cultivars. In both cultivars the protein HvPIP1 was accumulated in the highest amounts at 27 °C. On the other hand, the barley mutants with a BR deficiency or with BR signalling disturbances were characterised by an altered accumulation level of PM H+-ATPase, the aquaporin HvPIP1 transcript and protein (compared to the wild types), which may suggest the involvement of brassinosteroids in regulating PM H+-ATPase and aquaporin HvPIP1 at the transcriptional and translational levels.


Assuntos
Adenosina Trifosfatases/genética , Aquaporinas/genética , Hordeum/fisiologia , Proteínas de Plantas/genética , Aclimatação , Adenosina Trifosfatases/metabolismo , Aquaporinas/metabolismo , Brassinosteroides/metabolismo , Temperatura Baixa , Hordeum/genética , Temperatura Alta , Mutação , Proteínas de Plantas/metabolismo
9.
Nat Commun ; 10(1): 5516, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797871

RESUMO

Arabidopsis PIN2 protein directs transport of the phytohormone auxin from the root tip into the root elongation zone. Variation in hormone transport, which depends on a delicate interplay between PIN2 sorting to and from polar plasma membrane domains, determines root growth. By employing a constitutively degraded version of PIN2, we identify brassinolides as antagonists of PIN2 endocytosis. This response does not require de novo protein synthesis, but involves early events in canonical brassinolide signaling. Brassinolide-controlled adjustments in PIN2 sorting and intracellular distribution governs formation of a lateral PIN2 gradient in gravistimulated roots, coinciding with adjustments in auxin signaling and directional root growth. Strikingly, simulations indicate that PIN2 gradient formation is no prerequisite for root bending but rather dampens asymmetric auxin flow and signaling. Crosstalk between brassinolide signaling and endocytic PIN2 sorting, thus, appears essential for determining the rate of gravity-induced root curvature via attenuation of differential cell elongation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Gravitropismo/fisiologia , Raízes de Plantas/metabolismo , Arabidopsis/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Brassinosteroides/farmacologia , Endocitose/efeitos dos fármacos , Gravitropismo/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Meristema/efeitos dos fármacos , Meristema/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Transdução de Sinais , Esteroides Heterocíclicos/metabolismo , Esteroides Heterocíclicos/farmacologia
10.
J Agric Food Chem ; 67(49): 13526-13533, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31725271

RESUMO

Brassinosteroids (BRs) are important phytohormones and play critical roles during the growth and development of the plant. Numerous studies on biosynthesis and the signaling pathway of BRs have been performed, while the report about the metabolism of BRs is limited to carrots. In this study, we identified a homologous gene of AtCYP734A1/BAS1 (DCAR_009214), named DcBAS1, from carrots based on the data of the genome. The Arabidopsis overexpression line hosting the DcBAS1 gene was a dwarf and had crinkled blades and shortened petioles. Exogenous BL treatment rescued its growth and stem elongation. In addition, overexpressing DcBAS1 inhibited the cellulose synthesis in transgenic Arabidopsis plants. Results of quantitative real-time polymerase chain reaction revealed that overexpression of DcBAS1 inhibited the expression levels of AtCESAs genes (AtCESA1, AtCESA3, and AtCESA6), which are involved in cellulose synthesis in primary cell walls. AtBES1, which can be active by BR signaling, was also inhibited. These results revealed that DcBAS1 is the important gene involved in BR metabolism in carrots. Overexpression of DcBAS1 reduced the level of endogenous BRs and inhibited the cellulose synthesis in transgenic Arabidopsis plants.


Assuntos
Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Celulose/biossíntese , Daucus carota/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Daucus carota/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
11.
BMC Plant Biol ; 19(1): 409, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533628

RESUMO

BACKGROUND: Brassinosteroids (BRs) are a new group of plant hormones and play important roles in plant growth and development. However, little information is available if BRs could regulate spikelet development in rice (Oryza sativa L.) especially under soil-drying conditions. This study investigated whether and how BRs mediate the effect of soil-drying on spikelet differentiation and degeneration in rice. A rice cultivar was field-grown and exposed to three soil moisture treatments during panicle development, that is, well-watered (WW), moderate soil-drying (MD) and severe soil-drying (SD). RESULTS: Compared with the WW treatment, the MD treatment enhanced BRs biosynthesis in young panicles, increased spikelet differentiation and reduced spikelet degeneration. The SD treatment had the opposite effects. Changes in expression levels of key rice inflorescence development genes (OsAPO2 and OsTAW1), ascorbic acid (AsA) content, and activities of enzymes involved AsA synthesis and recycle, and amount of nonstructural carbohydrates (NSC) in young panicles were consistent with those in BRs levels, whereas hydrogen peroxide (H2O2) content showed opposite trend. Knockdown of the BRs synthesis gene OsD11 or application of a BRs biosynthesis inhibitor to young panicles markedly decreased OsAPO2 and OsTAW1 expression levels, BRs and AsA contents, activities of enzymes involved AsA synthesis and recycle, NSC amount in rice panicles and spikelet differentiation but increased the H2O2 content and spikelet degeneration compared to the control (the wide type or application of water). The opposite effects were observed when exogenous BRs were applied. CONCLUSIONS: The results suggest that BRs mediate the effect of soil-drying on spikelet differentiation and degeneration, and elevated BRs levels in rice panicles promote spikelet development under MD by enhancing inflorescence meristem activity, AsA recycle and NSC partitioning to the growing panicles.


Assuntos
Brassinosteroides/metabolismo , Oryza/metabolismo , Ácido Ascórbico/metabolismo , Solo
12.
DNA Cell Biol ; 38(11): 1292-1302, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31560570

RESUMO

Endogenous phytohormones auxin (indole-3-acetic acid [IAA]), abscisic acid (ABA), gibberellin (GA3), and brassinosteroid (BR) play a role in responses to drought stress in higher plants. Tea plant is one of the major economic corps worldwide. The tender shoots of tea plants are the main source for tea production. The effects of drought stress on endogenous IAA, ABA, GA3, and BR metabolisms in tender shoots of tea plants need to be illustrated. In this study, a total of 17 IAA-related genes, 17 ABA-related genes, 18 GA3-related genes, and 8 BR-related genes were identified under drought stress in tender shoots of tea plants, respectively. By using a combination of phytohormone determination, phylogenetic tree construction and sequence analysis, gene expression profiles, functional classification, Kyoto encyclopedia of genes and genomes enrichment, and distribution of genes analysis, we have demonstrated that IAA, ABA, GA3, and BR metabolisms might participate in the regulation of the response to drought stress in tender shoots of tea plants. The expression level of CsLYCE negatively correlated with ABA accumulation under drought stress. Our findings could shed new light on the effects of drought stress on the IAA, ABA, GA3, and BR metabolisms in tender shoots of tea plants.


Assuntos
Ácido Abscísico/metabolismo , Brassinosteroides/metabolismo , Camellia sinensis , Secas , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/genética , Ácido Abscísico/genética , Camellia sinensis/genética , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Giberelinas/genética , Redes e Vias Metabólicas/genética , Reguladores de Crescimento de Planta/genética , Reguladores de Crescimento de Planta/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Estresse Fisiológico/genética
13.
Environ Pollut ; 255(Pt 2): 113256, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563783

RESUMO

The presence of pesticide residues in fresh fruits and vegetables poses a serious threat to human health. Brassinosteroids (BRs) can reduce pesticide residues in plants, but the underlying mechanisms still remain unclear. Here, we identified a tomato glutaredoxin gene GRXS25 which was induced by 24-epibrassinolide (EBR) and chlorothalonil (CHT) in a way dependent on apoplastic reactive oxygen species (ROS). Silencing of GRXS25 in tomato abolished EBR-induced glutathione S-transferases (GSTs) gene expression and activity, leading to an increased CHT residue. Yeast two-hybrid and bimolecular fluorescence complementation assays showed protein-protein interaction between GRXS25 and a transcription factor TGA2. Electrophoretic mobility shift and chromatin immunoprecipitation assays indicated that TGA2 factor bound to the TGACG-motif in the GST3 promoter. While silencing of TGA2 strongly compromised, overexpression of TGA2 enhanced expression of GST genes and CHT residue metabolism. Our results suggest that BR-induced apoplastic ROS trigger metabolism of pesticide residue in tomato plants through activating TGA2 factor via GRXS25-dependent posttranslational redox modification. Activation of plant detoxification through physiological approaches has potential implication in improving the food safety of agricultural products.


Assuntos
Brassinosteroides/metabolismo , Glutarredoxinas/metabolismo , Lycopersicon esculentum/fisiologia , Nitrilos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Esteroides Heterocíclicos
14.
Plant Physiol Biochem ; 143: 119-128, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31493672

RESUMO

Brassinosteroids (BRs) have been rarely tested for their effective roles in mitigation of deleterious effects of water stress (WS) on plants. In addition, the contribution of nitric oxide (NO) in BR-improved plant tolerance to water stress needs to be elucidated. So, a trial was carried out to uncover the contribution of NO in BR-induced tolerance of pepper plants to WS. For well-watered and water-stressed plants, soil water availability was sustained at 80% and 40% of the full water storage capacity, respectively. BR (24-epibrassinolide, EB; 1.0 µM) was sprayed to the leaves of both well-watered and water stressed-pepper plants every two days for 10 days prior to the initiation of stress treatment. After starting WS treatment, cPTIO was sprayed to plant leaves twice a week for four weeks. Water stress caused a reduced plant growth and oxidative stress, but the application of EB increased plant growth and reversed the oxidative stress. The EB treatment increased endogenous NO and reinforced antioxidant defence systems, but the cPTIO application reversed the NO levels, downregulated the antioxidant defence systems, and aggravated oxidative damages caused by WS. These results show that EB-induced NO generation and NO-mediated antioxidant defence systems might be crucial mechanisms for EB-improved tolerance of pepper plants to WS. So, both EB and NO jointly are responsible for achieving improved tolerance of pepper plants to water stress.


Assuntos
Antioxidantes/metabolismo , Capsicum/metabolismo , Óxido Nítrico/metabolismo , Brassinosteroides/metabolismo , Clorofila/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Fotossíntese
15.
Molecules ; 24(16)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434211

RESUMO

Iron is an essential plant micronutrient. It is a component of numerous proteins and participates in cell redox reactions; iron deficiency results in a reduction in nutritional quality and crop yields. Volatiles from the rhizobacterium Arthrobacter agilis UMCV2 induce iron acquisition mechanisms in plants. However, it is not known whether microbial volatiles modulate other metabolic plant stress responses to reduce the negative effect of iron deficiency. Mass spectrometry has great potential to analyze metabolite alterations in plants exposed to biotic and abiotic factors. Direct liquid introduction-electrospray-mass spectrometry was used to study the metabolite profile in Medicago truncatula due to iron deficiency, and in response to microbial volatiles. The putatively identified compounds belonged to different classes, including pigments, terpenes, flavonoids, and brassinosteroids, which have been associated with defense responses against abiotic stress. Notably, the levels of these compounds increased in the presence of the rhizobacterium. In particular, the analysis of brassinolide by gas chromatography in tandem with mass spectrometry showed that the phytohormone increased ten times in plants grown under iron-deficient growth conditions and exposed to microbial volatiles. In this mass spectrometry-based study, we provide new evidence on the role of A. agilis UMCV2 in the modulation of certain compounds involved in stress tolerance in M. truncatula.


Assuntos
Arthrobacter/metabolismo , Brassinosteroides/metabolismo , Ferro/metabolismo , Medicago truncatula/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Compostos Orgânicos Voláteis/farmacologia , Inoculantes Agrícolas , Brassinosteroides/análise , Análise por Conglomerados , Medicago truncatula/efeitos dos fármacos , Medicago truncatula/crescimento & desenvolvimento , Modelos Biológicos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Estresse Fisiológico
16.
Science ; 365(6454): 658-664, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31416957

RESUMO

Increased planting densities have boosted maize yields. Upright plant architecture facilitates dense planting. Here, we cloned UPA1 (Upright Plant Architecture1) and UPA2, two quantitative trait loci conferring upright plant architecture. UPA2 is controlled by a two-base sequence polymorphism regulating the expression of a B3-domain transcription factor (ZmRAVL1) located 9.5 kilobases downstream. UPA2 exhibits differential binding by DRL1 (DROOPING LEAF1), and DRL1 physically interacts with LG1 (LIGULELESS1) and represses LG1 activation of ZmRAVL1 ZmRAVL1 regulates brd1 (brassinosteroid C-6 oxidase1), which underlies UPA1, altering endogenous brassinosteroid content and leaf angle. The UPA2 allele that reduces leaf angle originated from teosinte, the wild ancestor of maize, and has been lost during maize domestication. Introgressing the wild UPA2 allele into modern hybrids and editing ZmRAVL1 enhance high-density maize yields.


Assuntos
Grão Comestível/anatomia & histologia , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Zea mays/anatomia & histologia , Zea mays/genética , Alelos , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Brassinosteroides/metabolismo , Quimera , Clonagem Molecular , Domesticação , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Edição de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo Genético , Locos de Características Quantitativas
17.
J Agric Food Chem ; 67(35): 9757-9771, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31373492

RESUMO

BAK1 effects on plant stress responses have been well documented, but little is known regarding its effects on plant growth. In this study, we functionally characterized MdBAK1. Overexpressing MdBAK1 in Arabidopsis thaliana and apple trees promoted growth. Longitudinal stem cells were longer in transgenic plants than in wild-type plants. The size and number of cells and the area of the transverse stem were greater in the transgenic lines than in the wild-type plants. Moreover, transgenic A. thaliana and apple plants were more sensitive to an exogenous brassinosteroid. A transcriptome analysis of wild-type and transgenic apple revealed that MdBAK1 overexpression activated the brassinosteroid and ethylene signals, xylem production, and stress responses. Trend and Venn analyses indicated that carbohydrate, energy, and hormone metabolic activities were greater in transgenic plants during different periods. Moreover, a weighted gene coexpression network analysis proved that carbohydrate, hormone, and xylem metabolism as well as cell growth may be critical for MdBAK1-mediated apple tree growth and development. Compared with the corresponding levels in wild-type plants, the endogenous brassinosteroid, cytokinin, starch, sucrose, trehalose, glucose, fructose, and total sugar contents were considerably different in transgenic plants. Our results imply that MdBAK1 helps to regulate the growth of apple tree through the above-mentioned pathways. These findings provide new information regarding the effects of MdBAK1 onplant growth and development.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Malus/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Etilenos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais
18.
BMC Genomics ; 20(1): 644, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409283

RESUMO

BACKGROUND: The thermo-sensitive genic male sterility (TGMS) of Brassica napus facilitates reproductive researches and hybrid seed production. Considering the complexity and little information about the molecular mechanism involved in B. napus TGMS, comparative transcriptomic analyses were peroformed for the sterile (160S-MS) and fertile (160S-MF) flowers to identify potential crucial genes and pathways associated with TGMS. RESULTS: In total, RNA-seq analysis showed that 2202 genes (561 up-regulated and 1641 down-regulated) were significantly differentially expressed in the fertile flowers of 160S-MF at 25 °C when compared the sterile flower of 160S-MS at 15 °C. Detailed analysis revealed that expression changes in genes encoding heat shock proteins, antioxidant, skeleton protein, GTPase and calmodulin might be involved in TGMS of B. napus. Moreover, gene expression of some key members in plant hormone signaling pathways, such as auxin, gibberellins, jasmonic acid, abscisic acid, brassinosteroid signalings, were significantly surppressed in the flowers of 160S, suggesting that these genes might be involved in the regulation in B. napus TGMS. Here, we also found that transcription factor MADS, NFY, HSF, MYB/C and WRKY might play a crucial role in male fertility under the high temperature condition. CONCLUSION: High temperature can significant affect gene expression in the flowers. The findings in the current study improve our understanding of B. napus TGMS at the molecular level and also provide an effective foundation for male fertility researches in other important economic crops.


Assuntos
Brassica napus/genética , Brassica napus/fisiologia , Perfilação da Expressão Gênica , Infertilidade das Plantas/genética , Temperatura , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Brassica napus/metabolismo , Brassinosteroides/metabolismo , Ciclopentanos/metabolismo , Genes de Plantas/genética , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Oxilipinas/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Estresse Fisiológico/genética
19.
Int J Mol Sci ; 20(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395813

RESUMO

Vascular tissues essentially regulate water, nutrient, photo-assimilate, and phytohormone logistics throughout the plant body. Boron (B) is crucial for the development of the vascular tissue in many dicotyledonous plant taxa and B deficiency particularly affects the integrity of phloem and xylem vessels, and, therefore, functionality of long-distance transport. We hypothesize that changes in the plants' B nutritional status evoke differential responses of the vasculature and the mesophyll. However, direct analyses of the vasculature in response to B deficiency are lacking, due to the experimental inaccessibility of this tissue. Here, we generated biochemical and physiological understanding of B deficiency response reactions in common plantain (Plantago major L.), from which pure and intact vascular bundles can be extracted. Low soil B concentrations affected quantitative distribution patterns of various phytohormones, sugars and macro-, and micronutrients in a tissue-specific manner. Vascular sucrose levels dropped, and sucrose loading into the phloem was reduced under low B supply. Phytohormones responded selectively to B deprivation. While concentrations of abscisic acid and salicylic acid decreased at low B supply, cytokinins and brassinosteroids increased in the vasculature and the mesophyll, respectively. Our results highlight the biological necessity to analyze nutrient deficiency responses in a tissue- rather organ-specific manner.


Assuntos
Boro/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/metabolismo , Plantago/metabolismo , Sacarose/metabolismo , Brassinosteroides/metabolismo , Citocininas/metabolismo , Floema/metabolismo , Xilema/metabolismo
20.
Methods Mol Biol ; 2026: 201-213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31317415

RESUMO

Many aspects of light-controlled metabolism and development of plants depend on hormonal pathways. Here, a method is described to identify such hormonal dependence in light-regulated processes. A number of compounds-hormones and chemicals which interfere with hormonal pathways-are listed because of their usefulness in pharmacological treatment experiments. As an example for practical use of such compounds, elongation growth is discussed. An experimental setup is described in which plants are grown so that their structures develop predominantly in a two-dimensional plane. Time-lapse imaging is used to follow the plants in time, and image analysis reveals changes in plant morphology.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Luz , Arabidopsis/efeitos da radiação , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo
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