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1.
Crit Rev Biotechnol ; 41(1): 63-71, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33028118

RESUMO

Phosphorus (P) is an essential macronutrient for all living organisms. Importantly, plants require a large amount of P to grow, and P deficiency causes huge losses in plant production. Although this issue can be mitigated by the appropriate use of phosphate (Pi) rock-derived P fertilizers, phosphate rock is a finite natural resource. Moreover, the increased demand for food as a result of our growing global population is another factor contributing to a prospective P crisis. While creating crops that are resilient to Pi deficiency presents great scientific challenge, the current progress in our understanding of how plants regulate Pi homeostasis offers some opportunities for further study. In this review, we present the published research supporting these opportunities, which are based on the molecular mechanisms that plants have evolved to respond to P deficiency. First, we focus on recent advances in P sensing and signaling pathways in the regulation of root system architecture. Next, we describe the mechanisms that regulate Pi transport and accumulation, in a Pi- (or other nutrient) dependent manner. Integrating these data will help to design an innovative strategy for improving Pi nutrition in plants. In addition, this will help with Pi scarcity, one of the challenges facing agriculture in the twenty first century.


Assuntos
Agricultura , Fertilizantes , Fosfatos , Agricultura/tendências , Produtos Agrícolas/fisiologia , Fosfatos/metabolismo , Fósforo
2.
Plant J ; 105(3): 786-799, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33169459

RESUMO

Tiller number is one of the most important agronomic traits that determine rice (Oryza sativa) yield. Active growth of tiller bud (TB) requires high amount of mineral nutrients; however, the mechanism underlying the distribution of mineral nutrients to TB with low transpiration is unknown. Here, we found that the distribution of Zn to TB is mediated by OsZIP4, one of the ZIP (ZRT, IRT-like protein) family members. The expression of OsZIP4 was highly detected in TB and nodes, and was induced by Zn deficiency. Immunostaining analysis revealed that OsZIP4 was mainly expressed in phloem of diffuse vascular bundles in the nodes and the axillary meristem. The mutation of OsZIP4 did not affect the total Zn uptake, but altered Zn distribution; less Zn was delivered to TB and new leaf, but more Zn was retained in the basal stems at the vegetative growth stage. Bioimaging analysis showed that the mutant aberrantly accumulated Zn in enlarged and transit vascular bundles of the basal node, whereas in wild-type high accumulation of Zn was observed in the meristem part. At the reproductive stage, mutation of OsZIP4 resulted in delayed panicle development, which is associated with decreased Zn distribution to the panicles. Collectively, OsZIP4 is involved in transporting Zn to the phloem of diffuse vascular bundles in the nodes for subsequent distribution to TBs and other developing tissues. It also plays a role in transporting Zn to meristem cells in the TBs.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Zinco/metabolismo , Transporte Biológico , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/crescimento & desenvolvimento , Fenótipo , Floema/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Distribuição Tecidual , Zinco/farmacocinética , Isótopos de Zinco/farmacocinética
3.
Plants (Basel) ; 9(9)2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32854449

RESUMO

Iron (Fe) homeostasis is essential for plant growth and development, and it is strictly regulated by a group of transcriptional factors. Iron-related transcription factor 3 (OsIRO3) was previously identified as a negative regulator for Fe deficiency response in rice. However, the molecular mechanisms by which OsIRO3 regulate Fe homeostasis is unclear. Here, we report that OsIRO3 is essential for responding to Fe deficiency and maintaining Fe homeostasis in rice. OsIRO3 is expressed in the roots, leaves, and base nodes, with a higher level in leaf blades at the vegetative growth stage. Knockout of OsIRO3 resulted in a hypersensitivity to Fe deficiency, with severe necrosis on young leaves and defective root development. The iro3 mutants accumulated higher levels of Fe in the shoot under Fe-deficient conditions, associated with upregulating the expression of OsNAS3, which lead to increased accumulation of nicotianamine (NA) in the roots. Further analysis indicated that OsIRO3 can directly bind to the E-box in the promoter of OsNAS3. Moreover, the expression of typical Fe-related genes was significantly up-regulated in iro3 mutants under Fe-sufficient conditions. Thus, we conclude that OsIRO3 plays a key role in responding to Fe deficiency and regulates NA levels by directly, negatively regulating the OsNAS3 expression.

4.
J Clin Lab Anal ; 34(9): e23331, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32841434

RESUMO

BACKGROUND: Nucleic acid amplification tests (NAATs) are being used increasing to detection of CT (Chlamydia trachomatis) and NG (Neisseria gonorrhoeae) infections for superior sensitivity and specificity than other tests. Male first-void urine (FVU) sample is the optimal sample type for detection of CT and NG by NAATs. Although not being the recommended by NAATs, clinician-collected urethra swab (CCUS) is perhaps a good alternative sample type compared with the FVU sample in men. METHODS: Paired samples (FVU and CCUS) from one hundred male outpatients were simultaneously detected by urine pattern and swab pattern using cobas 4800 CT/NG assay on cobas 4800 system for the detection of CT and NG, respectively. And twenty-one positive controls were also detected on cobas 4800 system. RESULTS: The CT/NG cycle thresholds (Ct) value of urine pattern is lower than that of swab pattern for the same positive samples (clinical samples and positive controls) on the cobas 4800 CT/NG assay. The final CT/NG results of two sample patterns from patients were highly consistent except for four discordant results. CONCLUSION: CCUS is validated for a good alternative sample type for the CT/NG detection on the cobas 4800 system in this study.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Gonorreia/diagnóstico , Neisseria gonorrhoeae/isolamento & purificação , Uretra/metabolismo , Adulto , Infecções por Chlamydia/microbiologia , Seguimentos , Gonorreia/microbiologia , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , Curva ROC , Kit de Reagentes para Diagnóstico , Estudos Retrospectivos , Manejo de Espécimes
7.
Int J Mol Sci ; 19(11)2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30423990

RESUMO

The uptake and transport of iron (Fe) in plants are both important for plant growth and human health. However, little is known about the mechanism of Fe transport in plants, especially for crops. In the present study, the function of yellow stripe-like 13 (YSL13) in rice was analyzed. OsYSL13 was highly expressed in leaves, especially in leaf blades, whereas its expression was induced by Fe deficiency both in roots and shoots. Furthermore, the expression level of OsYSL13 was higher in older leaves than that in younger leaves. OsYSL13 was located in the plasma membrane. Metal measurement revealed that Fe concentrations were lower in the youngest leaf and higher in the older leaves of the osysl13 mutant under both Fe sufficiency and deficiency conditions, compared with the wild type and two complementation lines. Moreover, the Fe concentrations in the brown rice and seeds of the osysl13 mutant were also reduced. Opposite results were found in OsYSL13 overexpression lines. These results suggest that OsYSL13 is involved in Fe distribution in rice.


Assuntos
Ferro/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Mutação/genética , Oryza/genética , Oryza/fisiologia , Fenótipo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Transporte Proteico , Reprodução
8.
Plant Cell ; 30(10): 2267-2285, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30254029

RESUMO

Alternative splicing (AS) of pre-mRNAs promotes transcriptome and proteome diversity and plays important roles in a wide range of biological processes. However, the role of AS in maintaining mineral nutrient homeostasis in plants is largely unknown. To clarify this role, we obtained whole transcriptome RNA sequencing data from rice (Oryza sativa) roots grown in the presence or absence of several mineral nutrients (Fe, Zn, Cu, Mn, and P). Our systematic analysis revealed 13,291 alternatively spliced genes, representing ∼53.3% of the multiexon genes in the rice genome. As the overlap between differentially expressed genes and differentially alternatively spliced genes is small, a molecular understanding of the plant's response to mineral deficiency is limited by analyzing differentially expressed genes alone. We found that the targets of AS are highly nutrient-specific. To verify the role of AS in mineral nutrition, we characterized mutants in genes encoding Ser/Arg (SR) proteins that function in AS. We identified several SR proteins as critical regulators of Zn, Mn, and P nutrition and showed that three SR protein-encoding genes regulate P uptake and remobilization between leaves and shoots of rice, demonstrating that AS has a key role in regulating mineral nutrient homeostasis in rice.


Assuntos
Processamento Alternativo , Minerais/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Homeostase/fisiologia , Mutação , Fosfatos/metabolismo , Fosfatos/farmacocinética , Fósforo/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo
9.
Plant Cell Physiol ; 59(10): 2039-2051, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29939322

RESUMO

Deficiency of copper (Cu) causes low fertility in many plant species, but the molecular mechanisms underlying distribution of Cu to the floral organs are poorly understood. Here, we found that a member of yellow-stripe like (YSL) family, YSL16 encoding the Cu-nicotianamine (Cu-NA) transporter, was highly expressed in the rachilla, with less expression in the palea and lemma of rice (Oryza sativa). ß-Glucuronidase (GUS) staining of transgenic rice carrying the OsYSL16 promoter-GUS showed that OsYSL16 was mainly expressed in vascular bundles of the rachilla as well as the palea and lemma. Knockout of OsYSL16 resulted in decreased Cu distribution to the stamens, but increased distribution to the palea and lemma. A short-term (24 h) 65Cu labeling experiment confirmed increased Cu concentration of palea and lemma in the mutant. Furthermore, we found that redistribution of Cu from the palea and lemma was impaired in the osysl16 mutant after exposure to Cu-free solution. The osysl16 mutant showed low pollen germination, but this was rescued by addition of Cu in the medium. Our results indicate that OsYSL16 expressed in the vascular bundles of the rachilla is important for preferential distribution of Cu to the stamens, while OsYSL16 in vascular bundles of the palea and lemma is involved in Cu redistribution under Cu-limited conditions in rice.


Assuntos
Cobre/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética
10.
Int J Mol Sci ; 19(2)2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29364145

RESUMO

Lignin is one of the main components of plant cell wall and it is a natural phenolic polymer with high molecular weight, complex composition and structure. Lignin biosynthesis extensively contributes to plant growth, tissue/organ development, lodging resistance and the responses to a variety of biotic and abiotic stresses. In the present review, we systematically introduce the biosynthesis of lignin and its regulation by genetic modification and summarize the main biological functions of lignin in plants and their applications. We hope this review will give an in-depth understanding of the important roles of lignin biosynthesis in various plants' biological processes and provide a theoretical basis for the genetic improvement of lignin content and composition in energy plants and crops.


Assuntos
Lignina/genética , Lignina/metabolismo , Plantas/genética , Plantas/metabolismo , Adaptação Biológica , Vias Biossintéticas , Parede Celular , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Lignina/química , Desenvolvimento Vegetal/genética , Doenças das Plantas/genética , Fenômenos Fisiológicos Vegetais , Característica Quantitativa Herdável , Estresse Fisiológico
11.
Plant Sci ; 264: 1-8, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28969789

RESUMO

Cadmium (Cd) is one of the most toxic heavy metal elements in nature, and it causes serious damage to plant cells. Here, we report that a transcription factor OsMYB45 is involved in Cd stress response in rice. OsMYB45 is highly expressed in rice leaves, husks, stamens, pistils, and lateral roots, and its expression is induced by Cd stress. OsMYB45 fused to green fluorescent protein localized to the cell nucleus in onion epidermal cells. Mutation of OsMYB45 resulted in hypersensitivity to Cd treatment, and the concentration of H2O2 in the leaves of mutant nearly doubled, while catalase (CAT) activity was halved compared with the wild-type. Moreover, gene expression analysis indicated that OsCATA and OsCATC expression is significantly lower in the mutant than in the wild-type. In addition, overexpression of OsMYB45 in the mutant complemented the mutant phenotype. Taken together, OsMYB45 plays an important role in tolerance to Cd stress in rice.


Assuntos
Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/genética , Fatores de Transcrição/metabolismo , Catalase/metabolismo , Flores/efeitos dos fármacos , Flores/genética , Flores/fisiologia , Expressão Gênica , Genes Reporter , Peróxido de Hidrogênio/metabolismo , Mutação , Cebolas/efeitos dos fármacos , Cebolas/genética , Cebolas/fisiologia , Especificidade de Órgãos , Oryza/efeitos dos fármacos , Oryza/fisiologia , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Proteínas Recombinantes de Fusão , Estresse Fisiológico , Fatores de Transcrição/genética
12.
Metallomics ; 9(7): 989, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28660265

RESUMO

Correction for 'Arbuscular mycorrhizal fungi enhance the copper tolerance of Tagetes patula through the sorption and barrier mechanisms of intraradical hyphae' by Xishi Zhou et al., Metallomics, 2017, DOI: .

13.
Metallomics ; 9(7): 936-948, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28613326

RESUMO

Arbuscular mycorrhizal fungi (AMF) are widespread soil fungi that can form endosymbiotic structures with the root systems of most plants and can improve the tolerance of host plants to heavy metals. In the present study, we investigated the effects of AMF (Glomus coronatum) inoculation on the tolerance of Tagetes patula L. to Cu. Almost all of the non-mycorrhizal plants exposed to 100 µM Cu died after 3 d, whereas phytotoxicity was only observed in mycorrhizal plants that were exposed to Cu concentrations greater than 100 µM. Analysing the dynamic accumulation of Cu indicated that, after 7 d of Cu exposure, less Cu was absorbed or accumulated by mycorrhizal plants than by control plants, and significantly less Cu was translocated to the shoots. Meanwhile, analysing the root morphology, the integrity of the root plasma membranes, the photosynthesis rate, and the content of essential elements of plants growing in cultures with 50 µM Cu revealed that AMF inoculation markedly alleviated the toxic effects of Cu stress on root system activity, photosynthesis rate, and mineral nutrient accumulation. In addition, to understand the Cu allocation, an energy spectrum analysis of Cu content at the transverse section of root tips was conducted and subsequently provided direct evidence that intraradical hyphae at the root endodermis could selectively immobilise large amounts of Cu. Indeed, the sorption and barrier mechanisms of AMF hyphae reduce Cu toxicity in the roots of T. patula and eventually enhance the plants' Cu tolerance.


Assuntos
Cobre/toxicidade , Glomeromycota/fisiologia , Hifas/fisiologia , Micorrizas/fisiologia , Tagetes/microbiologia , Tagetes/fisiologia , Biomassa , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Clorofila/metabolismo , Glomeromycota/efeitos dos fármacos , Hifas/efeitos dos fármacos , Micorrizas/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Transpiração Vegetal/efeitos dos fármacos , Transpiração Vegetal/fisiologia , Tagetes/efeitos dos fármacos , Tagetes/ultraestrutura
14.
Artigo em Inglês | MEDLINE | ID: mdl-28387709

RESUMO

With the rapid progress of industrialization, the effects of environmental contamination on plant toxicity, and subsequently on human health, is a growing concern. For example, the heavy metal pollution of soil such as that caused by cadmium (Cd) is a serious threat. Therefore, screening for pollution-safe edible plants is an essential approach for growing plants under heavy metal-contaminated soils. In the current study, 35 Chinese cabbage (Brassica pekinensis L.) cultivars were selected with the aim of screening for Cd-safe cultivars (CSCs), analyzing their safety, and exploring the mechanism of Cd accumulation. Our field-culture experiments revealed that the Cd content in the edible parts of the cultivars were varied and were determined to possibly be CSCs. Hydroponics experiments were used to simulate six different degrees of soil contamination (high and low Cd concentrations) on possible CSCs. The results indicated a significant difference (p < 0.05) in Cd concentration in the cultivars, and verified the safety of these possible CSCs. The analyses of the transport coefficient and expression levels showed that the differences in Cd accumulation among the Chinese cabbage cultivars were related to the expression of genes involved in absorption and transport rather than a root-to-shoot translocation limitation.


Assuntos
Brassica/metabolismo , Cádmio/metabolismo , Monitoramento Ambiental , Contaminação de Alimentos/análise , Metais Pesados/metabolismo , Poluentes do Solo/análise , Brassica/química , Cádmio/análise , Poluição Ambiental/análise , Abastecimento de Alimentos , Hidroponia , Metais Pesados/análise , Raízes de Plantas/química , Brotos de Planta/química , Brotos de Planta/metabolismo , Solo/química , Poluentes do Solo/química , Poluentes do Solo/metabolismo
15.
Int J Mol Sci ; 18(2)2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28146098

RESUMO

Laccases are encoded by a multigene family and widely distributed in plant genomes where they play roles oxidizing monolignols to produce higher-order lignin involved in plant development and stress responses. We identified 30 laccase genes (OsLACs) from rice, which can be divided into five subfamilies, mostly expressed during early development of the endosperm, growing roots, and stems. OsLACs can be induced by hormones, salt, drought, and heavy metals stresses. The expression level of OsLAC10 increased 1200-fold after treatment with 20 µM Cu for 12 h. The laccase activities of OsLAC10 were confirmed in an Escherichia coli expression system. Lignin accumulation increased in the roots of Arabidopsis over-expressing OsLAC10 (OsLAC10-OX) compared to wild-type controls. After growth on 1/2 Murashige and Skoog (MS) medium containing toxic levels of Cu for seven days, roots of the OsLAC10-OX lines were significantly longer than those of the wild type. Compared to control plants, the Cu concentration decreased significantly in roots of the OsLAC10-OX line under hydroponic conditions. These results provided insights into the evolutionary expansion and functional divergence of OsLAC family. In addition, OsLAC10 is likely involved in lignin biosynthesis, and reduces the uptake of Cu into roots required for Arabidopsis to develop tolerance to Cu.


Assuntos
Adaptação Biológica , Arabidopsis/genética , Arabidopsis/metabolismo , Cobre/metabolismo , Expressão Ectópica do Gene , Lacase/genética , Oryza/genética , Estresse Fisiológico , Adaptação Biológica/genética , Transporte Biológico , Análise por Conglomerados , Escherichia coli/genética , Escherichia coli/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Plantas Geneticamente Modificadas , Estresse Fisiológico/genética
16.
J Microbiol Immunol Infect ; 49(3): 359-62, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25081985

RESUMO

PURPOSE: The aim of this study was to estimate the prevalence and antimicrobial susceptibility of Ureaplasma urealyticum and Mycoplasma hominis among female outpatients treated for genital infection at a Chinese hospital from January 1, 2009 to December 31, 2013. METHODS: Samples from 6051 female outpatients were analyzed using Mycoplasma Identification and Antimicrobial Susceptibility Testing (ID/AST). RESULTS: The overall prevalence of U. urealyticum was higher than the prevalence of single M. hominis infection (31.2% vs 0.7%) and coinfections (31.2% vs. 1.9%). The percentage of U. urealyticum and/or M. hominis detected in the 30-39 year age group was greater than in the other age groups. More than 94.6% of the U. urealyticum isolates, 100% of the M. hominis isolates, and 84.3% of the isolates from coinfections were susceptible to doxycycline, minocycline, and tetracycline. More than 69.2% of the U. urealyticum isolates were susceptible to azithromycin, erythromycin, clarithromycin, and roxithromycin, but > 95.6% of the M. hominis isolates and 89.6% of the isolates from coinfections were resistant to these antibiotics. Acetylspiramycin, sparfloxacin, levofloxacin, ciprofloxacin, and ofloxacin were inactive against more than one-half of the isolates. More than 75.6% of the M. hominis isolates were susceptible to spectinomycin, but > 87.1% of the U. urealyticum and 93.3% of the coinfection isolates were resistant to this antibiotic. Isolates from three coinfections were completely resistant to the 14 antibiotics. CONCLUSION: The determination of antimicrobial susceptibility of these mycoplasma species is often crucial for optimal antimicrobial therapy of infected outpatients.


Assuntos
Antibacterianos/farmacologia , Infecções por Mycoplasma/epidemiologia , Mycoplasma hominis/efeitos dos fármacos , Infecções por Ureaplasma/epidemiologia , Ureaplasma urealyticum/efeitos dos fármacos , Adulto , China/epidemiologia , Coinfecção/tratamento farmacológico , Farmacorresistência Bacteriana , Feminino , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma hominis/isolamento & purificação , Pacientes Ambulatoriais , Estudos Retrospectivos , Infecções por Ureaplasma/tratamento farmacológico , Ureaplasma urealyticum/isolamento & purificação
17.
J Hazard Mater ; 294: 99-108, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25867584

RESUMO

Metallothioneins (MTs) are low-molecular-weight, cysteine-rich metal-binding proteins found in numerous genera and species, but their functions in abiotic stress tolerance remain unclear. Here, a MT gene from Oryza sativa, OsMT2c, was isolated and characterized, encoding a type 2 MT, and observed expression in the roots, leaf sheathes, and leaves, but only weak expression in seeds. OsMT2c was upregulated by copper (Cu) and hydrogen peroxide (H2O2) treatments. Excessive Cu elicited a rapid and sustained production and release of H2O2 in rice, and exogenous H2O2 scavengers N,N'-dimethylthiourea (DMTU) and ascorbic acid (Asc) decreased H2O2 production and OsMT2c expression. Furthermore, the expression of OsMT2c increased in the osapx2 mutant in which the H2O2 levels were higher than in wild-type (WT) plants. These results showed that Cu increased MT2c expression through the production and accumulation of Cu-induced H2O2 in O. sativa. In addition, the transgenic OsMT2c-overexpressing Arabidopsis displayed improved tolerance to Cu stress and exhibited increased reactive oxygen species (ROS) scavenging ability compared to WT and empty-vector (Ev) seedlings.


Assuntos
Arabidopsis/efeitos dos fármacos , Cobre/toxicidade , Peróxido de Hidrogênio/metabolismo , Metalotioneína/genética , Oryza/genética , Proteínas de Plantas/genética , Arabidopsis/genética , Cobre/farmacologia , Genes de Plantas , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sementes/efeitos dos fármacos , Sementes/metabolismo , Regulação para Cima
18.
Front Plant Sci ; 6: 1136, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26734039

RESUMO

Widely-spread cadmium (Cd) pollution in the soil threatens both crop production and human health. How plants deal with the excess Cd are largely unknown. To evaluate the molecular mechanism by which plants respond to Cd stress, rice seedlings were treated with two concentrations of Cd and subjected to deep RNA sequencing. Comprehensive RNA-Seq analysis of rice roots under two gradients of Cd treatment revealed 1169 Cd toxicity-responsive genes. These genes were involved in the reactive oxygen species scavenging system, stress response, cell wall formation, ion transport, and signal transduction. Nine out of 93 predicted long non-coding RNAs (lncRNAs) were detected as Cd-responsive lncRNAs due to their high correlation with the Cd stress response. In addition, we analyzed alternative splicing (AS) events under different Cd concentrations. Four hundred and seventy-six differential alternatively spliced genes with 542 aberrant splicing events were identified. GO analysis indicated that these genes were highly enriched in oxidation reduction and cellular response to chemical stimulus. Real-time qRT-PCR validation analysis strengthened the reliability of our RNA-Seq results. The results suggest that post-transcriptional AS regulation may also be involved in plant responses to high Cd stress.

19.
Plant Cell Environ ; 36(1): 224-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22755510

RESUMO

Iron (Fe) is an essential micronutrient element for plant growth. Regulation of Fe-deficiency signalling networks is one of the many functions reported for basic helix-loop-helix (bHLH) transcription factors in plants. In the present study, OsbHLH133 was found to be induced by Fe-deficiency conditions in Oryza sativa. Insertional inactivation of OsbHLH133 (bhlh133) resulted in growth retardation, with enhanced Fe concentration seen in shoots, and reduced Fe concentration in roots. Overexpression of OsbHLH133 had the opposite effect, that is resulted in an enhanced Fe concentration in roots and reduced Fe concentration in shoots and also in xylem sap. Microarray analysis showed that some of the genes encoding Fe-related functions were up-regulated under Fe-sufficient conditions, in bhlh133 mutant plants compared to wild-type plants. Significant differential expression of a number of signalling pathways, including calcium signalling, was also seen in bhlh133 plants compared to wild-type plants, independent of Fe conditions.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ferro/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , DNA Bacteriano , Regulação da Expressão Gênica de Plantas , Mutagênese Insercional , Análise de Sequência com Séries de Oligonucleotídeos , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Regulação para Cima
20.
Plant Cell ; 24(9): 3767-82, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23012434

RESUMO

Cu is an essential element for plant growth, but the molecular mechanisms of its distribution and redistribution within the plants are unknown. Here, we report that Yellow stripe-like16 (YSL16) is involved in Cu distribution and redistribution in rice (Oryza sativa). Rice YSL16 was expressed in the roots, leaves, and unelongated nodes at the vegetative growth stage and highly expressed in the upper nodes at the reproductive stage. YSL16 was expressed at the phloem of nodes and vascular tissues of leaves. Knockout of this gene resulted in a higher Cu concentration in the older leaves but a lower concentration in the younger leaves at the vegetative stage. At the reproductive stage, a higher Cu concentration was found in the flag leaf and husk, but less Cu was present in the brown rice, resulting in a significant reduction in fertility in the knockout line. Isotope labeling experiments with (65)Cu showed that the mutant lost the ability to transport Cu-nicotianamine from older to younger leaves and from the flag leaf to the panicle. Rice YSL16 transported the Cu-nicotianamine complex in yeast. Taken together, our results indicate that Os-YSL16 is a Cu-nicotianamine transporter that is required for delivering Cu to the developing young tissues and seeds through phloem transport.


Assuntos
Cobre/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Oryza/metabolismo , Floema/metabolismo , Ácido Azetidinocarboxílico/análogos & derivados , Ácido Azetidinocarboxílico/metabolismo , Sequência de Bases , Transporte Biológico/genética , Cátions/análise , Cátions/metabolismo , Cobre/análise , Fertilidade , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Proteínas de Membrana Transportadoras/genética , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Cebolas/genética , Cebolas/metabolismo , Especificidade de Órgãos , Oryza/genética , Fenótipo , Floema/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Reprodução , Sementes/genética , Sementes/metabolismo , Análise de Sequência de DNA
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