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1.
Molecules ; 26(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199058

RESUMO

We measured and studied the growth parameters and the qualitative and quantitative composition of the flavones of hairy roots of the Scutellaria genus: S. lateriflora, S. przewalskii and S. pycnoclada. Hairy roots were obtained using wild-type Agrobacterium rhizogenes A4 by co-cultivation of explants (cotyledons) in a suspension of Agrobacterium. The presence of the rol-genes was confirmed by PCR analysis. The hairy roots of the most studied plant from the Scutellaria genus, S. baicalensis, were obtained earlier and used as a reference sample. HPLC-MS showed the predominance of four main flavones (baicalin, baicalein, wogonin and wogonoside) in the methanol extracts of the studied hairy roots. In addition to the four main flavones, the other substances which are typical to the aerial part of plants were found in all the extracts: apigenin, apigetrin, scutellarin and chrysin-7-O-ß-d-glucuronide. According to the total content of flavones, the hairy roots of the studied skullcaps form the following series: S. przewalskii (33 mg/g dry weight) > S. baicalensis (17.04 mg/g dry weight) > S. pycnoclada (12.9 mg/g dry weight) > S. lateriflora (4.57 mg/g dry weight). Therefore, the most promising producer of anti-coronavirus flavones is S. przewalskii.


Assuntos
Antivirais/química , Flavonas/química , Scutellaria/química , Agrobacterium/crescimento & desenvolvimento , Agrobacterium/metabolismo , Antivirais/isolamento & purificação , Antivirais/farmacologia , Cromatografia Líquida de Alta Pressão , Flavonas/isolamento & purificação , Flavonas/farmacologia , Células Vegetais/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Scutellaria/crescimento & desenvolvimento , Scutellaria/metabolismo , Espectrometria de Massas em Tandem
2.
BMC Plant Biol ; 21(1): 318, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217217

RESUMO

BACKGROUND: Cassava (Manihot esculenta Crantz) efficiently accumulates starch in its storage roots. However, how photosynthates are transported from the leaves to the phloem (especially how they are unloaded into parenchymal cells of storage roots) remains unclear. RESULTS: Here, we investigated the sucrose unloading pattern and its impact on cassava storage root development using microstructural and physiological analyses, namely, carboxyfluorescein (CF) and C14 isotope tracing. The expression profiling of genes involved in symplastic and apoplastic transport was performed, which included enzyme activity, protein gel blot analysis, and transcriptome sequencing analyses. These finding showed that carbohydrates are transported mainly in the form of sucrose, and more than 54.6% was present in the stem phloem. Sucrose was predominantly unloaded symplastically from the phloem into storage roots; in addition, there was a shift from apoplastic to symplastic unloading accompanied by the onset of root swelling. Statistical data on the microstructures indicated an enrichment of plasmodesmata within sieve, companion, and parenchyma cells in the developing storage roots of a cultivar but not in a wild ancestor. Tracing tests with CF verified the existence of a symplastic channel, and [14C] Suc demonstrated that sucrose could rapidly diffuse into root parenchyma cells from phloem cells. The relatively high expression of genes encoding sucrose synthase and associated proteins appeared in the middle and late stages of storage roots but not in primary fibrous roots, or secondary fibrous roots. The inverse expression pattern of sucrose transporters, cell wall acid invertase, and soluble acid invertase in these corresponding organs supported the presence of a symplastic sucrose unloading pathway. The transcription profile of genes involved in symplastic unloading and their significantly positive correlation with the starch yield at the population level confirmed that symplastic sucrose transport is vitally important in the development of cassava storage roots. CONCLUSIONS: In this study, we revealed that the cassava storage root phloem sucrose unloading pattern was predominantly a symplastic unloading pattern. This pattern is essential for efficient starch accumulation in high-yielding varieties compared with low-yielding wild ancestors.


Assuntos
Manihot/metabolismo , Floema/fisiologia , Fotossíntese/fisiologia , Raízes de Plantas/metabolismo , Amido/metabolismo , Transporte Biológico , Biomassa , Parede Celular/metabolismo , Difusão , Fluoresceínas/metabolismo , Regulação da Expressão Gênica de Plantas , Manihot/genética , Modelos Biológicos , Floema/citologia , Floema/ultraestrutura , Plasmodesmos/metabolismo , Frações Subcelulares/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo
3.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205973

RESUMO

The Arabidopsis AtCRK5 protein kinase is involved in the establishment of the proper auxin gradient in many developmental processes. Among others, the Atcrk5-1 mutant was reported to exhibit a delayed gravitropic response via compromised PIN2-mediated auxin transport at the root tip. Here, we report that this phenotype correlates with lower superoxide anion (O2•-) and hydrogen peroxide (H2O2) levels but a higher nitric oxide (NO) content in the mutant root tips in comparison to the wild type (AtCol-0). The oxidative stress inducer paraquat (PQ) triggering formation of O2•- (and consequently, H2O2) was able to rescue the gravitropic response of Atcrk5-1 roots. The direct application of H2O2 had the same effect. Under gravistimulation, correct auxin distribution was restored (at least partially) by PQ or H2O2 treatment in the mutant root tips. In agreement, the redistribution of the PIN2 auxin efflux carrier was similar in the gravistimulated PQ-treated mutant and untreated wild type roots. It was also found that PQ-treatment decreased the endogenous NO level at the root tip to normal levels. Furthermore, the mutant phenotype could be reverted by direct manipulation of the endogenous NO level using an NO scavenger (cPTIO). The potential involvement of AtCRK5 protein kinase in the control of auxin-ROS-NO-PIN2-auxin regulatory loop is discussed.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Arabidopsis/crescimento & desenvolvimento , Transporte Biológico/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Gravitação , Gravitropismo/genética , Peróxido de Hidrogênio/farmacologia , Meristema/genética , Meristema/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Paraquat/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
4.
Int J Mol Sci ; 22(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207734

RESUMO

Rhizobia are soil proteobacteria able to engage in a nitrogen-fixing symbiotic interaction with legumes that involves the rhizobial infection of roots and the bacterial invasion of new organs formed by the plant in response to the presence of appropriate bacterial partners. This interaction relies on a complex molecular dialogue between both symbionts. Bacterial N-acetyl-glucosamine oligomers called Nod factors are indispensable in most cases for early steps of the symbiotic interaction. In addition, different rhizobial surface polysaccharides, such as exopolysaccharides (EPS), may also be symbiotically relevant. EPS are acidic polysaccharides located out of the cell with little or no cell association that carry out important roles both in free-life and in symbiosis. EPS production is very complexly modulated and, frequently, co-regulated with Nod factors, but the type of co-regulation varies depending on the rhizobial strain. Many studies point out a signalling role for EPS-derived oligosaccharides in root infection and nodule invasion but, in certain symbiotic couples, EPS can be dispensable for a successful interaction. In summary, the complex regulation of the production of rhizobial EPS varies in different rhizobia, and the relevance of this polysaccharide in symbiosis with legumes depends on the specific interacting couple.


Assuntos
Fabaceae , Raízes de Plantas , Polissacarídeos Bacterianos/metabolismo , Rhizobium/metabolismo , Simbiose/fisiologia , Fabaceae/metabolismo , Fabaceae/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia
5.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206151

RESUMO

The saccharification of sweetpotato storage roots is a common phenomenon in the cooking process, which determines the edible quality of table use sweetpotato. In the present study, two high saccharified sweetpotato cultivars (Y25, Z13) and one low saccharified cultivar (X27) in two growth periods (S1, S2) were selected as materials to reveal the molecular mechanism of sweetpotato saccharification treated at high temperature by transcriptome sequencing and non-targeted metabolome determination. The results showed that the comprehensive taste score, sweetness, maltose content and starch change of X27 after steaming were significantly lower than those of Y25 and Z13. Through transcriptome sequencing analysis, 1918 and 1520 differentially expressed genes were obtained in the two periods of S1 and S2, respectively. Some saccharification-related transcription factors including MYB families, WRKY families, bHLH families and inhibitors were screened. Metabolic analysis showed that 162 differentially abundant metabolites related to carbohydrate metabolism were significantly enriched in starch and sucrose capitalization pathways. The correlation analysis between transcriptome and metabolome confirmed that the starch and sucrose metabolic pathways were significantly co-annotated, indicating that it is a vitally important metabolic pathway in the process of sweetpotato saccharification. The data obtained in this study can provide valuable resources for follow-up research on sweetpotato saccharification and will provide new insights and theoretical basis for table use sweetpotato breeding in the future.


Assuntos
Metabolismo dos Carboidratos , Temperatura Alta , Ipomoea batatas/metabolismo , Raízes de Plantas/metabolismo , Transcriptoma , Manipulação de Alimentos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metabolômica , Amido/metabolismo , Sacarose/metabolismo
6.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206311

RESUMO

Chemotaxis, the ability of motile bacteria to direct their movement in gradients of attractants and repellents, plays an important role during the rhizosphere colonization by rhizobacteria. The rhizosphere is a unique niche for plant-microbe interactions. Root exudates are highly complex mixtures of chemoeffectors composed of hundreds of different compounds. Chemotaxis towards root exudates initiates rhizobacteria recruitment and the establishment of bacteria-root interactions. Over the last years, important progress has been made in the identification of root exudate components that play key roles in the colonization process, as well as in the identification of the cognate chemoreceptors. In the first part of this review, we summarized the roles of representative chemoeffectors that induce chemotaxis in typical rhizobacteria and discussed the structure and function of rhizobacterial chemoreceptors. In the second part we reviewed findings on how rhizobacterial chemotaxis and other root-microbe interactions promote the establishment of beneficial rhizobacteria-plant interactions leading to plant growth promotion and protection of plant health. In the last part we identified the existing gaps in the knowledge and discussed future research efforts that are necessary to close them.


Assuntos
Bactérias , Quimiotaxia , Exsudatos de Plantas , Plantas/microbiologia , Rizosfera , Fenômenos Fisiológicos Bacterianos , Microbiota , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plantas/metabolismo
7.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208611

RESUMO

Transcription factors are proteins that directly bind to regulatory sequences of genes to modulate and adjust plants' responses to different stimuli including biotic and abiotic stresses. Sedentary plant parasitic nematodes, such as beet cyst nematode, Heterodera schachtii, have developed molecular tools to reprogram plant cell metabolism via the sophisticated manipulation of genes expression, to allow root invasion and the induction of a sequence of structural and physiological changes in plant tissues, leading to the formation of permanent feeding sites composed of modified plant cells (commonly called a syncytium). Here, we report on the AtMYB59 gene encoding putative MYB transcription factor that is downregulated in syncytia, as confirmed by RT-PCR and a promoter pMyb59::GUS activity assays. The constitutive overexpression of AtMYB59 led to the reduction in A. thaliana susceptibility, as indicated by decreased numbers of developed females, and to the disturbed development of nematode-induced syncytia. In contrast, mutant lines with a silenced expression of AtMYB59 were more susceptible to this parasite. The involvement of ABA in the modulation of AtMYB59 gene transcription appears feasible by several ABA-responsive cis regulatory elements, which were identified in silico in the gene promoter sequence, and experimental assays showed the induction of AtMYB59 transcription after ABA treatment. Based on these results, we suggest that AtMYB59 plays an important role in the successful parasitism of H. schachtii on A. thaliana roots.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/parasitologia , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Fatores de Transcrição/genética , Tylenchoidea/fisiologia , Animais , Arabidopsis/ultraestrutura , Resistência à Doença/genética , Interações Hospedeiro-Parasita , Fenótipo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Raízes de Plantas/ultraestrutura , Regiões Promotoras Genéticas
8.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068175

RESUMO

Low phosphorus (P) availability is a major limiting factor for potatoes. P fertilizer is applied to enhance P availability; however, it may become toxic when plants accumulate at high concentrations. Therefore, it is necessary to gain more knowledge of the morphological and biochemical processes associated with P deficiency and toxicity for potatoes, as well as to explore an alternative approach to ameliorate the P deficiency condition. A comprehensive study was conducted (I) to assess plant morphology, mineral allocation, and metabolites of potatoes in response to P deficiency and toxicity; and (II) to evaluate the potency of plant growth-promoting rhizobacteria (PGPR) in improving plant biomass, P uptake, and metabolites at low P levels. The results revealed a reduction in plant height and biomass by 60-80% under P deficiency compared to P optimum. P deficiency and toxicity conditions also altered the mineral concentration and allocation in plants due to nutrient imbalance. The stress induced by both P deficiency and toxicity was evident from an accumulation of proline and total free amino acids in young leaves and roots. Furthermore, root metabolite profiling revealed that P deficiency reduced sugars by 50-80% and organic acids by 20-90%, but increased amino acids by 1.5-14.8 times. However, the effect of P toxicity on metabolic changes in roots was less pronounced. Under P deficiency, PGPR significantly improved the root and shoot biomass, total root length, and root surface area by 32-45%. This finding suggests the potency of PGPR inoculation to increase potato plant tolerance under P deficiency.


Assuntos
Fósforo/metabolismo , Desenvolvimento Vegetal , Rhizobiaceae/fisiologia , Solanum tuberosum/anatomia & histologia , Solanum tuberosum/metabolismo , Estresse Fisiológico , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/microbiologia
9.
Int J Mol Sci ; 22(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34063053

RESUMO

Increased soil salinity, and therefore accumulation of ions, is one of the major abiotic stresses of cultivated plants that negatively affect their growth and yield. Among Medicago species, only Medicago truncatula, which is a model plant, has been extensively studied, while research regarding salinity responses of two important forage legumes of Medicago sativa (M. sativa) and Medicago arborea (M. arborea) has been limited. In the present work, differences between M. arborea, M. sativa and their hybrid Alborea were studied regarding growth parameters and metabolomic responses. The entries were subjected to three different treatments: (1) no NaCl application (control plants), (2) continuous application of 100 mM NaCl (acute stress) and (3) gradual application of NaCl at concentrations of 50-75-150 mM by increasing NaCl concentration every 10 days. According to the results, M. arborea maintained steady growth in all three treatments and appeared to be more resistant to salinity. Furthermore, results clearly demonstrated that M. arborea presented a different metabolic profile from that of M. sativa and their hybrid. In general, it was found that under acute and gradual stress, M. sativa overexpressed saponins in the shoots while M. arborea overexpressed saponins in the roots, which is the part of the plant where most of the saponins are produced and overexpressed. Alborea did not perform well, as more metabolites were downregulated than upregulated when subjected to salinity stress. Finally, saponins and hydroxycinnamic acids were key players of increased salinity tolerance.


Assuntos
Hibridização Genética , Medicago/metabolismo , Medicago/fisiologia , Metaboloma , Tolerância ao Sal , Metabolismo Secundário , Análise de Variância , Medicago/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Caules de Planta/anatomia & histologia , Análise de Componente Principal
10.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34074049

RESUMO

The vegetative phase transition is a prerequisite for flowering in angiosperm plants. Mulberry miR156 has been confirmed to be a crucial factor in the vegetative phase transition in Arabidopsis thaliana. The over-expression of miR156 in transgenic Populus × canadensis dramatically prolongs the juvenile phase. Here, we find that the expression of mno-miR156 decreases with age in all tissues in mulberry, which led us to study the hierarchical action of miR156 in mulberry. Utilizing degradome sequencing and dual-luciferase reporter assays, nine MnSPLs were shown to be directly regulated by miR156. The results of yeast one-hybrid and dual-luciferase reporter assays also revealed that six MnSPLs could recognize the promoter sequences of mno-miR172 and activate its expression. Our results demonstrate that mno-miR156 performs its role by repressing MnSPL/mno-miR172 pathway expression in mulberry. This work uncovered a miR156/SPLs/miR172 regulation pathway in the development of mulberry and fills a gap in our knowledge about the molecular mechanism of vegetative phase transition in perennial woody plants.


Assuntos
Envelhecimento/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , MicroRNAs/metabolismo , Morus/metabolismo , Proteínas de Plantas/metabolismo , Envelhecimento/genética , Arabidopsis/genética , Biologia Computacional , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Hydrastis/genética , Hydrastis/metabolismo , MicroRNAs/genética , Morus/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Populus/genética , Populus/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima
11.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068646

RESUMO

Nowadays, the use of biostimulants to reduce agrochemical input is a major trend in agriculture. In this work, we report on calcium phosphate particles (CaP) recovered from the circular economy, combined with natural humic substances (HSs), to produce a plant biostimulant. CaPs were obtained by the thermal treatment of Salmo salar bones and were subsequently functionalized with HSs by soaking in a HS water solution. The obtained materials were characterized, showing that the functionalization with HS did not sort any effect on the bulk physicochemical properties of CaP, with the exception of the surface charge that was found to get more negative. Finally, the effect of the materials on nutrient uptake and translocation in the early stages of development (up to 20 days) of two model species of interest for horticulture, Valerianella locusta and Diplotaxis tenuifolia, was assessed. Both species exhibited a similar tendency to accumulate Ca and P in hypogeal tissues, but showed different reactions to the treatments in terms of translocation to the leaves. CaP and CaP-HS treatments lead to an increase of P accumulation in the leaves of D. tenuifolia, while the treatment with HS was found to increase only the concentration of Ca in V. locusta leaves. A low biostimulating effect on both plants' growth was observed, and was mainly scribed to the low concentration of HS in the tested materials. In the end, the obtained material showed promising results in virtue of its potential to elicit phosphorous uptake and foliar translocation by plants.


Assuntos
Agricultura/economia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Substâncias Húmicas/análise , Plantas/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Peixes , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plântula/anatomia & histologia , Plântula/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Valerianella/química , Difração de Raios X
12.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069886

RESUMO

Although spinach (Spinacia oleracea L.) is considered to be one of the most nutrient-rich leafy vegetables, it is also a potent accumulator of anti-nutritional oxalate. Reducing oxalate content would increase the nutritional value of spinach by enhancing the dietary bioavailability of calcium and other minerals. This study aimed to investigate the proposed hypothesis that a complex network of genes associated with intrinsic metabolic and physiological processes regulates oxalate homeostasis in spinach. Transcriptomic (RNA-Seq) analysis of the leaf and root tissues of two spinach genotypes with contrasting oxalate phenotypes was performed under normal physiological conditions. A total of 2308 leaf- and 1686 root-specific differentially expressed genes (DEGs) were identified in the high-oxalate spinach genotype. Gene Ontology (GO) analysis of DEGs identified molecular functions associated with various enzymatic activities, while KEGG pathway analysis revealed enrichment of the metabolic and secondary metabolite pathways. The expression profiles of genes associated with distinct physiological processes suggested that the glyoxylate cycle, ascorbate degradation, and photorespiratory pathway may collectively regulate oxalate in spinach. The data support the idea that isocitrate lyase (ICL), ascorbate catabolism-related genes, and acyl-activating enzyme 3 (AAE3) all play roles in oxalate homeostasis in spinach. The findings from this study provide the foundation for novel insights into oxalate metabolism in spinach.


Assuntos
Oxalatos/metabolismo , Spinacia oleracea/genética , Spinacia oleracea/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , RNA-Seq/métodos , Spinacia oleracea/fisiologia , Transcriptoma/genética
13.
BMC Plant Biol ; 21(1): 282, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154533

RESUMO

BACKGROUND: Phosphorus (P), being one of the essential components of nucleic acids, cell membranes and enzymes, indispensable for diverse cellular processes like photosynthesis/carbohydrate metabolism, energy production, redox homeostasis and signaling. Crop yield is severely affected due to Phosphate (Pi) deficiency; and to cope with Pi-deficiency, plants have evolved several strategies. Some rice genotypes are compatible with low Pi availability, whereas others are sensitive to Pi deficiency. However, the underlying molecular mechanism for low Pi tolerance remains largely unexplored. RESULT: Several studies were carried out to understand Pi-deficiency responses in rice at seedling stage, but few of them targeted molecular aspects/responses of Pi-starvation at the advanced stage of growth. To delineate the molecular mechanisms for low Pi tolerance, a pair of contrasting rice (Oryza sativa L.) genotypes [viz. Pusa-44 (Pi-deficiency sensitive) and its near isogenic line (NIL-23, Pi-deficiency tolerant) harboring Phosphorus uptake 1 (Pup1) QTL from an aus landrace Kasalath] were used. Comparative morphological, physiological, and biochemical analyses confirmed some of the well-known findings. Transcriptome analysis of shoot and root tissues from 45-day-old rice plants grown hydroponically under P-sufficient (16 ppm Pi) or P-starved (0 ppm Pi) medium revealed that Pi-starvation stress causes global transcriptional reprogramming affecting several transcription factors, signaling pathways and other regulatory genes. We could identify several significantly up-regulated genes in roots of NIL-23 under Pi-starvation which might be responsible for the Pi starvation tolerance. Pathway enrichment analysis indicated significant role of certain phosphatases, transporters, transcription factors, carbohydrate metabolism, hormone-signaling, and epigenetic processes in improving P-starvation stress tolerance in NIL-23. CONCLUSION: We report the important candidate mechanisms for Pi acquisition/solubilization, recycling, remobilization/transport, sensing/signalling, genetic/epigenetic regulation, and cell wall structural changes to be responsible for P-starvation tolerance in NIL-23. The study provides some of the novel information useful for improving phosphorus-use efficiency in rice cultivars.


Assuntos
Adaptação Fisiológica , Oryza/genética , Oryza/metabolismo , Fósforo/metabolismo , Fosfatase Ácida/metabolismo , Epigênese Genética , Genes de Plantas , Genótipo , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Locos de Características Quantitativas , Plântula/crescimento & desenvolvimento , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transcriptoma
14.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069632

RESUMO

In tobacco, the efficiency of Zn translocation to shoots depends on Zn/Cd status. Previous studies pointed to the specific contribution of root parts in the regulation of this process, as well as the role of NtZIP4A/B (from the ZIP family; Zrt Irt-like Proteins). Here, to verify this hypothesis, NtZIP4A/B RNAi lines were generated. Then, in plants exposed to combinations of Zn and Cd concentrations in the medium, the consequences of NtZIP4A/B suppression for the translocation of both metals were determined. Furthermore, the apical, middle, and basal root parts were examined for accumulation of both metals, for Zn localization (using Zinpyr-1), and for modifications of the expression pattern of ZIP genes. Our results confirmed the role of NtZIP4A/B in the control of Zn/Cd-status-dependent transfer of both metals to shoots. Furthermore, they indicated that the middle and basal root parts contributed to the regulation of this process by acting as a reservoir for excess Zn and Cd. Expression studies identified several candidate ZIP genes that interact with NtZIP4A/B in the root in regulating Zn and Cd translocation to the shoot, primarily NtZIP1-like in the basal root part and NtZIP2 in the middle one.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Tabaco/metabolismo , Zinco/metabolismo , Adenosina Trifosfatases/metabolismo , Transporte Biológico/genética , Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas/genética , Homeostase , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética
15.
BMC Plant Biol ; 21(1): 269, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34116636

RESUMO

BACKGROUND: Raising nitrogen use efficiency of crops by improving root system architecture is highly essential not only to reduce costs of agricultural production but also to mitigate climate change. The physiological mechanisms of how biochar affects nitrogen assimilation by crop seedlings have not been well elucidated. RESULTS: Here, we report changes in root system architecture, activities of the key enzymes involved in nitrogen assimilation, and cytokinin (CTK) at the seedling stage of cotton with reduced urea usage and biochar application at different soil layers (0-10 cm and 10-20 cm). Active root absorption area, fresh weight, and nitrogen agronomic efficiency increased significantly when urea usage was reduced by 25% and biochar was applied in the surface soil layer. Glutamine oxoglutarate amino transferase (GOGAT) activity was closely related to the application depth of urea/biochar, and it increased when urea/biochar was applied in the 0-10 cm layer. Glutamic-pyruvic transaminase activity (GPT) increased significantly as well. Nitrate reductase (NR) activity was stimulated by CTK in the very fine roots but inhibited in the fine roots. In addition, AMT1;1, gdh3, and gdh2 were significantly up-regulated in the very fine roots when urea usage was reduced by 25% and biochar was applied. CONCLUSION: Nitrogen assimilation efficiency was significantly affected when urea usage was reduced by 25% and biochar was applied in the surface soil layer at the seedling stage of cotton. The co-expression of gdh3 and gdh2 in the fine roots increased nitrogen agronomic efficiency. The synergistic expression of the ammonium transporter gene and gdh3 suggests that biochar may be beneficial to amino acid metabolism.


Assuntos
Carvão Vegetal/metabolismo , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Gossypium/anatomia & histologia , Raízes de Plantas/anatomia & histologia , Plântula/anatomia & histologia
16.
Ecotoxicol Environ Saf ; 220: 112411, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111661

RESUMO

This study focused on the effects of eight medicinal plant extracts on Solanum nigrum L. potential to accumulate Cd and Pb from soil. These medicinal plants were common and relatively cheap. The eight 10% water extracts were made from the peel of Citrus reticulata Blanco (PCR), fruit of Phyllanthus emblica L. (FPE), root of Pueraria Lobata (Willd.) Ohwi (RPL), rhizome of Polygonatum sibiricum Red (RPS), root of Astragalus propinquus Schischkin (RAP), bud of Hemerocallis citrina Baroni (BHC), seed of Nelumbo nucifera Gaertn (SNN) and fruit of Prunus mume (Sieb.) Sieb.etZuce (FPM). The results showed that among all exposures, the treatment with FPE resulted in the significant increase (p < 0.05) of Cd and Pb concentration in shoots and roots of S. nigrum by 32.5% and 65.2% for Cd, and 38.7% and 39.6% for Pb. The biomasses of S. nigrum in all plant extract treatments were not significantly changed (p < 0.05) compared to the control (CK). The Cd and Pb extraction rates of S. nigrum in FPE treatment were increased respectively by 60.5% and 40.5% compared to CK. Though the treatment with EDTA significantly improved (p < 0.05) the concentration of Cd and Pb of S. nigrum, the Cd and Pb masses (ug plant-1) of S. nigrum did not show any significant difference compared to the CK due to the significant decrease in the shoot (20.4%) and root (22.0%) biomasses. The chelative role of FPE might be relation with its higher polyphenolic compounds. However, not sure if the contents of polyphenolic compounds was the only differences between FPE and other additives. Thus, some unknown organic matters might also play active role. This study provided valuable information on improving the phytoremediation potential of hyperaccumulator.


Assuntos
Metais Pesados/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Poluentes do Solo/metabolismo , Solanum nigrum/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Biomassa , Quelantes/química , Quelantes/farmacologia , Extratos Vegetais/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Solanum nigrum/metabolismo
17.
Ecotoxicol Environ Saf ; 221: 112437, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34153540

RESUMO

Agricultural soils are receiving higher inputs of trace elements (TEs) from anthropogenic activities. Application of nanoparticles (NPs) in agriculture as nano-pesticides and nano-fertilizers has gained rapid momentum worldwide. The NPs-based fertilizers can facilitate controlled-release of nutrients which may be absorbed by plants more efficiently than conventional fertilizers. Due to their large surface area with high sorption capacity, NPs can be used to reduce excess TEs uptake by plants. The present review summarizes the effects of NPs on plant growth, photosynthesis, mineral nutrients uptake and TEs concentrations. It also highlights the possible mechanisms underlying NPs-mediated reduction of TEs toxicity at the soil and plant interphase. Nanoparticles are effective in immobilization of TEs in soil through alteration of their speciation and improving soil physical, chemical, and biological properties. At the plant level, NPs reduce TEs translocation from roots to shoots by promoting structural alterations, modifying gene expression, and improving antioxidant defense systems. However, the mechanisms underlying NPs-mediated TEs uptake and toxicity reduction vary with NPs type, mode of application, time of NPs exposure, and plant conditions (e.g., species, cultivars, and growth rate). The review emphasizes that NPs may provide new perspectives to resolve the problem of TEs toxicity in crop plants which may also reduce the food security risks. However, the potential of NPs in metal-contaminated soils is only just starting to be realized, and additional studies are required to explore the mechanisms of NPs-mediated TEs immobilization in soil and uptake by plants. Such future knowledge gap has been highlighted and discussed.


Assuntos
Nanopartículas , Plantas/efeitos dos fármacos , Oligoelementos/metabolismo , Oligoelementos/toxicidade , Agricultura , Metais/metabolismo , Metais/toxicidade , Raízes de Plantas/metabolismo , Plantas/metabolismo , Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade
18.
Ecotoxicol Environ Saf ; 221: 112415, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34171691

RESUMO

In order to understand the mechanisms of arsenic (As) accumulation and detoxification in aquatic plants exposed to different As species, a hydroponic experiment was conducted and the three aquatic plants (Hydrilla verticillata, Pistia stratiotes and Eichhornia crassipes) were exposed to different concentrations of As(III), As(V) and dimethylarsinate (DMA) for 10 days. The biomass, the surface As adsorption and total As adsorption of three plants were determined. Furthermore, As speciation in the culture solution and plant body, as well as the arsenate reductase (AR) activities of roots and shoots, were also analyzed. The results showed that the surface As adsorption of plants was far less than total As absorption. Compared to As(V), the plants showed a lower DMA accumulation. P. stratiotes showed the highest accumulation of inorganic arsenic but E. crassipes showed the lowest at the same As treatment. E. crassipes showed a strong ability to accumulate DMA. Results from As speciation analysis in culture solution showed that As(III) was transformed to As(V) in all As(III) treatments, and the oxidation rates followed as the sequence of H. verticillata>P. stratiotes>E. crassipes>no plant. As(III) was the predominant species in both roots (39.4-88.3%) and shoots (39-86%) of As(III)-exposed plants. As(V) and As(III) were the predominant species in roots (37-94%) and shoots (31.1-85.6%) in As(V)-exposed plants, respectively. DMA was the predominant species in both roots (23.46-100%) and shoots (72.6-100%) in DMA-exposed plants. The As(III) contents and AR activities in the roots of P. stratiotes and in the shoots of H. verticillata were significantly increased when exposed to 1 mg·L-1 or 3 mg·L-1 As(V). Therefore, As accumulation mainly occurred via biological uptake rather than physicochemical adsorption, and AR played an important role in As detoxification in aquatic plants. In the case of As(V)-exposed plants, their As tolerance was attributed to the increase of AR activities.


Assuntos
Araceae , Arseniato Redutases/metabolismo , Arsênio , Ácido Cacodílico , Eichhornia , Hydrocharitaceae , Proteínas de Plantas/metabolismo , Poluentes Químicos da Água , Adsorção , Araceae/química , Araceae/metabolismo , Arsênio/química , Arsênio/metabolismo , Ácido Cacodílico/química , Ácido Cacodílico/metabolismo , Eichhornia/química , Eichhornia/metabolismo , Hydrocharitaceae/química , Hydrocharitaceae/metabolismo , Hidroponia , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
19.
BMC Plant Biol ; 21(1): 285, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34157988

RESUMO

BACKGROUND: Angelica sinensis (Oliv.) Diels (A. sinensis) is a Chinese herb grown in different geographical locations. It contains numerous active components with therapeutic value. Rhizosphere microbiomes affect various aspects of plant performance, such as nutrient acquisition, growth and development and plant diseases resistance. So far, few studies have investigated how the microbiome effects level of active components of A. sinensis. This study investigated whether changes in rhizosphere microbial communities and metabolites of A. sinensis vary with the soil microenvironment. Soils from the two main A. sinensis-producing areas, Gansu and Yunnan Province, were used to conduct pot experiments. The soil samples were divided into two parts, one part was sterilized and the other was unsterilized planting with the seedling variety of Gansu danggui 90-01. All seedlings were allowed to grow for 180 days. At the end of the experiment, radix A. sinensis were collected and used to characterize growth targets and chemical compositions. Rhizosphere soils were subjected to microbial analyses. RESULTS: Changes in metabolic profiles and rhizosphere microbial communities of A. sinensis grown under different soil microenvironments were similar. The GN (Gansu non-sterilized), YN (Yunnan non-sterilized), GS (Gansu sterilized), and YS (Yunnan sterilized) groups were significantly separated. Notably, antagonistic bacteria such as Sphingomonas, Pseudomonas, Lysobacter, Pseudoxanthomonas, etc. were significantly (p < 0.05) enriched in Gansu soil compared with Yunnan soil. Moreover, senkyunolide I and ligustilide dimers which were enriched in GS group were strongly positively correlated with Pseudomonas parafulva; organic acids (including chlorogenic acid, dicaffeoylquinic acid and 5-feruloylquinic acid) and their ester coniferyl ferulate which were enriched in YS Group were positively associated with Gemmatimonadetes bacterium WY71 and Mucilaginibater sp., respectively. CONCLUSIONS: The soil microenvironment influences growth and level/type of active components in A. sinensis. Further studies should explore the functional features of quality-related bacteria, identify the key response genes and clarify the interactions between genes and soil environments. This will reveal the mechanisms that determine the quality formation of genuine A. sinensis.


Assuntos
Angelica sinensis/metabolismo , Microbiologia do Solo , Angelica sinensis/anatomia & histologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Rizosfera
20.
Ecotoxicol Environ Saf ; 220: 112392, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102395

RESUMO

Understanding the molecular mechanisms of cadmium (Cd) tolerance and accumulation in plants is important to address Cd pollution. In the present study, we performed comparative transcriptome analysis to identify the Cd response processes in the roots of two turnip landraces, KTRG-B14 (high-Cd accumulation) and KTRG-B36 (low-Cd accumulation). Two common enhanced processes, glutathione metabolism and antioxidant system, were identified in both landraces. However, some differential antioxidant processes are likely employed by two landraces, namely, several genes encoding peptide methionine sulfoxide reductases and thioredoxins were up-regulated in B14, whereas flavonoid synthesis was potentially induced to fight against oxidative stress in B36. In addition to the commonly upregulated ZINC INDUCED FACILITATOR 1-like gene in two landraces, different metal transporter-encoding genes identified in B14 (DETOXIFICATION 1) and B36 (PLANT CADMIUM RESISTANCE 2-like, probable zinc transporter 10, and ABC transporter C family member 3) were responsible for Cd accumulation and distribution in cells. Several genes that encode extensins were specifically upregulated in B14, which may improve Cd accumulation in cell walls or regulate root development to absorb more Cd. Meanwhile, the induced high-affinity nitrate transporter 2.1-like gene was also likely to contribute to the higher Cd accumulation in B14. However, Cd also caused some toxic symptoms in both landraces. Cd stress might inhibit iron uptake in both landraces whereas many apoenzyme-encoding genes were influenced in B36, which may be attributed to the interaction between Cd and other metal ions. This study provides novel insights into the molecular mechanism of plant root response to Cd at an early stage. The transporters and key enzymes identified in this study are helpful for the molecular-assisted breeding of low- or high-Cd-accumulating plant resources.


Assuntos
Brassica napus/genética , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo , Antioxidantes/metabolismo , Biodegradação Ambiental , Brassica napus/metabolismo , Glutationa/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Ferro/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Transcriptoma
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