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1.
Pestic Biochem Physiol ; 159: 85-90, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400788

RESUMO

RNA interference (RNAi) is a potentially useful pest control method because of its high specificity. Silencing the expression of important RNAi target genes of pests will block important biological processes and reduce pest damage. Ecdysone is a unique arthropod hormone and the ecdysone receptor (EcR) is a key factor in molting pathway. We investigated the possibility that dsRNA targeting of the EcR of Tetranychus cinnabarinus (TcEcR) could effectively block development from larvae to adults. The mRNA level of TcEcR was highest in the larva stage, and 73.1% of the mites failed to survive the larva stage when TcEcR expression was silenced. Only 11.7% of T. cinnabarinus ingesting dsRNA successfully developed into adults, while 86.7% in the control succeeded in molting across each stage. RNAi significantly increased the developmental intervals of T. cinnabarinus. Under the effects of dsRNA, development times for the larva and first nymph doubled. Phenotype of body size change and death were observed during the development of T. cinnabarinus ingesting dsRNA. These findings suggest that RNAi is a potential means for the control of T. cinnabarinus. Genes in hormone pathways such as EcR are possible RNAi targets.


Assuntos
Larva/metabolismo , Interferência de RNA/fisiologia , Receptores de Esteroides/metabolismo , Tetranychidae/metabolismo , Animais , Tamanho Corporal , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , RNA de Cadeia Dupla/genética , Receptores de Esteroides/genética , Tetranychidae/crescimento & desenvolvimento
2.
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
3.
J Agric Food Chem ; 67(35): 9877-9884, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398030

RESUMO

Heavy metal contaminants and nutrient deficiencies in soil negatively affect crop growth and human health. The plant cadmium resistance (PCR) protein transports heavy metals. The abundance of PCR is correlated with that of cell number regulator (CNR) protein, and the two proteins have similar conserved domains. Hence, CNR might also participate in heavy metal transport. We isolated and analyzed TaCNR5 from wheat (Triticum aestivum). The expression level of TaCNR5 in the shoots of wheat increased under cadmium (Cd), zinc (Zn), or manganese (Mn) treatments. Transgenic plants expressing TaCNR5 showed enhanced tolerance to Zn and Mn. Overexpression of TaCNR5 in Arabidopsis increased Cd, Zn, and Mn translocation from roots to shoots. The concentrations of Zn and Mn in rice grains were increased in transgenic plants expressing TaCNR5. These roles of TaCNR5 in the translocation and distribution of heavy metals mean that it has potential as a genetic biofortification tool to fortify cereal grains with micronutrients.


Assuntos
Manganês/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Triticum/genética , Zinco/metabolismo , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Biofortificação , Transporte Biológico , Cádmio/análise , Cádmio/metabolismo , Manganês/análise , Oryza/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Triticum/química , Triticum/metabolismo , Zinco/análise
4.
Ecotoxicol Environ Saf ; 182: 109397, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299476

RESUMO

Cadmium (Cd) is a serious threat to plants health. Though some genes have been reported to get involved in the regulation of tolerance to Cd, the mechanisms underlying this process are not fully understood. Na+/H+ antiporter (NHX1) plays an important role in Na+/H+ trafficking. The salt and cadmium stress tolerance were found to be enhanced by NHX1 in duckweed according to our previous study, however, its function in Cd2+ flux under Cd stress has not been studied. Here we explored the Cd2+ flux in wild type (WT) and NHX1 transgenic duckweed (NHX1) under Cd stress. We found that the Cd2+ influx in NHX1 duckweed was significantly declined, followed by an increased Cd2+ efflux after 20 min treatment of Cd, which resulted a less accumulation of Cd in NHX1. Reversely, inhibition of NHX1 by amiloride treatment, enhanced Cd2+ influx in NHX1 duckweed, subsequently delayed Cd2+ efflux in both genotypes of duckweed under Cd2+ shock. H+ efflux in NHX1 duckweed was lower compare with that in WT with 20 min Cd2+ shock. NHX1 also increased the pH value with Cd2+ stress in the transgenic rhizoid. These finding suggested a new function of NHX1 in regulation of Cd2+ and H+ flow during short-term Cd2+ shock.


Assuntos
Araceae/fisiologia , Cádmio/metabolismo , Poluentes Químicos da Água/metabolismo , Araceae/metabolismo , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio , Poluentes Químicos da Água/toxicidade
5.
J Agric Food Chem ; 67(28): 7986-7994, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282158

RESUMO

Compositional analyses were performed on samples of rice grain, straw, and derived bran obtained from golden rice event GR2E and near-isogenic control PSBRc82 rice grown at four locations in the Philippines during 2015 and 2016. Grain samples were analyzed for key nutritional components, including proximates, fiber, polysaccharides, fatty acids, amino acids, minerals, vitamins, and antinutrients. Samples of straw and bran were analyzed for proximates and minerals. The only biologically meaningful difference between GR2E and control rice was in levels of ß-carotene and other provitamin A carotenoids in the grain. Except for ß-carotene and related carotenoids, the compositional parameters of GR2E rice were within the range of natural variability of those components in conventional rice varieties with a history of safe consumption. Mean provitamin A concentrations in milled rice of GR2E can contribute up to 89-113% and 57-99% of the estimated average requirement for vitamin A for preschool children in Bangladesh and the Philippines, respectively.


Assuntos
Oryza/genética , Plantas Geneticamente Modificadas/química , Sementes/química , Aminoácidos/análise , Aminoácidos/metabolismo , Bangladesh , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Alimentos Geneticamente Modificados , Engenharia Genética , Valor Nutritivo , Oryza/química , Oryza/metabolismo , Filipinas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Provitaminas/análise , Provitaminas/metabolismo , Sementes/genética , Sementes/metabolismo , Vitamina A/análise , Vitamina A/metabolismo , beta Caroteno/análise , beta Caroteno/metabolismo
6.
J Agric Food Chem ; 67(28): 7898-7907, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282664

RESUMO

This study aimed to explore the effects of silencing HB12 and TT8 genes on protein utilization characteristics of alfalfa. Ground samples of 11 HB12-silenced (HB12i), 5 TT8-silenced (TT8i) and 4 wild type (WT) were incubated in a Daisy II incubator with N15 labeled ammonium sulfate for 0, 4, 8, 12, and 24 h. CP degradation and degradational kinetics, microbial nitrogen fractions, and protein metabolic profiles were determined. Moreover, relationships between protein profiles and FTIR spectral parameters were estimated. Results showed that transgenic alfalfa had lower CP degradation, microbial protein, and total available protein compared with WT, especially for HB12i. In addition, CP degradation and protein metabolic profiles were closely correlated with FTIR spectral parameters and thereby could be predicted from spectral parameters. In conclusion, silencing of HB12 and TT8 genes in alfalfa decreased protein degradational and metabolic profiles, which were predictable with FTIR spectral parameters.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Medicago sativa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rúmen/metabolismo , Ração Animal/análise , Animais , Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bovinos , Digestão , Proteínas de Homeodomínio/metabolismo , Cinética , Medicago sativa/química , Medicago sativa/metabolismo , Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteólise , Rúmen/química , Rúmen/microbiologia
7.
BMC Plant Biol ; 19(1): 298, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286900

RESUMO

BACKGROUND: Homeodomain-leucine zipper (HD-ZIP) transcription factors play important roles in the growth, development and stress responses of plants, including (presumably) physic nut (Jatropha curcas), which has high drought and salinity tolerance. However, although physic nut's genome has been released, there is little knowledge of the functions, expression profiles and evolutionary histories of the species' HD-ZIP genes. RESULTS: In this study, 32 HD-ZIP genes were identified in the physic nut genome (JcHDZs) and divided into four groups (I-IV) based on phylogenetic analysis with homologs from rice, maize and Arabidopsis. The analysis also showed that most of the JcHDZ genes were closer to members from Arabidopsis than to members from rice and maize. Of the 32 JcHDZ genes, most showed differential expression patterns among four tissues (root, stem cortex, leaf, and seed). Expression profile analysis based on RNA-seq data indicated that 15 of the JcHDZ genes respond to at least one abiotic stressor (drought and/or salinity) in leaves at least at one time point. Transient expression of a JcHDZ16-YFP fusion protein in Arabidopsis protoplasts cells showed that JcHDZ16 is localized in the nucleus. In addition, rice seedlings transgenically expressing JcHDZ16 had lower proline contents and activities of antioxidant enzymes (catalase and superoxide dismutase) together with higher relative electrolyte leakage and malondialdehyde contents under salt stress conditions (indicating higher sensitivity) than wild-type plants. The transgenic seedlings also showed increased sensitivity to exogenous ABA, and increases in the transcriptional abundance of several salt stress-responsive genes were impaired in their responses to salt stress. Further data on JcHDZ16-overexpressing plants subjected to salt stress treatment verified the putative role of JcHDZ genes in salt stress responses. CONCLUSION: Our results may provide foundations for further investigation of functions of JcHDZ genes in responses to abiotic stress, and promote application of JcHDZ genes in physic nut breeding.


Assuntos
Jatropha/genética , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Estudo de Associação Genômica Ampla , Jatropha/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
8.
Plant Sci ; 286: 28-36, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300139

RESUMO

MYB family genes act as important regulators modulating the response to abiotic stress in plants. However, much less is known about MYB proteins in cotton. Here, we found that a cotton MYB gene, GhMYB73, was induced by NaCl and abscisic acid (ABA). Silencing GhMYB73 expression in cotton increased sensitivity to salt stress. The cotyledon greening rate of Arabidopsis thaliana over-expressing GhMYB73 under NaCl or mannitol treatment was significantly enhanced during the seedling germination stage. What's more, several osmotic stress-induced genes, such as AtNHX1, AtSOS3 and AtP5CS1, were more highly induced in the over-expression lines than in wild type under salt treatment, supporting the hypothesis that GhMYB73 contributes to salinity tolerance by improving osmotic stress resistance. Arabidopsis lines over-expressing GhMYB73 had superior germination and cotyledon greening under ABA treatment, and some abiotic stress-induced genes involved in ABA pathways (AtPYL8, AtABF3, AtRD29B and AtABI5), had increased transcription levels under salt-stress conditions in these lines. Furthermore, we found that GhMYB73 physically interacts with GhPYL8 and AtPYL8, suggesting that GhMYB73 regulates ABA signaling during salinity stress response. Taken together, over-expression of GhMYB73 significantly increases tolerance to salt and ABA stress, indicating that it can potentially be used in transgenic technology approaches to improve cotton salt tolerance.


Assuntos
Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Gossypium/fisiologia , Proteínas de Plantas/genética , Estresse Salino/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Inativação Gênica , Genes myb , Gossypium/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Fatores de Transcrição/metabolismo
9.
J Agric Food Chem ; 67(31): 8559-8572, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298518

RESUMO

Avenin-like b protein is rich in cysteine residues, providing the possibility to form intermolecular disulfide bonds and then participate in glutenin polymerization. Site-directed mutagenesis was adopted to produce mutant avenin-like b gene encoding mutant avenin-like b protein, in which one tyrosine codon at the C-terminal is substituted by a cysteine codon. Compared with the control lines, both transgenic lines with wild-type and mutant avenin-like b genes demonstrated superior dough properties. While compared within the transgenic lines, the mutant lines showed relative weaker dough strength and decreased sodium-dodecyl-sulfate sedimentation volumes (from 69.7 mL in line WT alb-1 to 41.0 mL in line Mut alb-4). These inferior dough properties were accompanied by the lower contents of large-sized glutenin polymers, the decreased particle diameters of glutenin macropolymer (GMP), due to the lower content of intermolecular ß-sheets (from 39.48% for line WT alb-2 to 30.21% for line Mut alb-3) and the varied contents of disulfide bonds (from 137.37 µmol/g for line WT alb-1 to 105.49 µmol/g for line Mut alb-4) in wheat dough. The extra cysteine might alter the original disulfide bond structure, allowing cysteine residue usually involved in an intermolecular disulfide bond to become available for an intrachain disulfide bond. Avenin-like b proteins were detected in glutenin macropolymers, providing further evidence for this protein to participate in the polymerization of glutenin. This is the first time to investigate the effect of a specific cysteine residue in the avenin-like b protein on flour quality.


Assuntos
Cisteína/genética , Farinha/análise , Plantas Geneticamente Modificadas/genética , Prolaminas/genética , Triticum/genética , Pão/análise , Cisteína/metabolismo , Dissulfetos/química , Manipulação de Alimentos , Mutagênese Sítio-Dirigida , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/metabolismo , Prolaminas/metabolismo , Triticum/química , Triticum/metabolismo
10.
Plant Mol Biol ; 101(3): 257-268, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302867

RESUMO

KEY MESSAGE: The C-terminal cysteine-rich motif of NYE1/SGR1 affects chlorophyll degradation likely by mediating its self-interaction and conformational change, and somehow altering its Mg-dechelating activity in response to the changing redox potential. During green organ senescence in plants, the most prominent phenomenon is the degreening caused by net chlorophyll (Chl) loss. NON-YELLOWING1/STAY-GREEN1 (NYE1/SGR1) was recently reported to be able to dechelates magnesium (Mg) from Chl a to initiate its degradation, but little is known about the domain/motif basis of its functionality. In this study, we carried out a protein truncation assay and identified a conserved cysteine-rich motif (CRM, P-X3-C-X3-C-X-C2-F-P-X5-P) at its C terminus, which is essential for its function. Genetic analysis showed that all four cysteines in the CRM were irreplaceable, and enzymatic assays demonstrated that the mutation of each of the four cysteines affected its Mg-dechelating activity. The CRM plays a critical role in the conformational change and self-interaction of NYE1 via the formation of inter- and intra-molecular disulfide bonds. Our results may provide insight into how NYE1 responds to rapid redox changes during leaf senescence and in response to various environmental stresses.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Clorofila/química , Proteínas de Cloroplastos/metabolismo , Motivos de Aminoácidos , Quelantes/química , DNA Complementar/metabolismo , Dissulfetos , Regulação da Expressão Gênica de Plantas , Magnésio/química , Oxirredução , Fenótipo , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Conformação Proteica , Domínios Proteicos , Estresse Fisiológico
11.
J Agric Food Chem ; 67(26): 7466-7474, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184886

RESUMO

The ZMM28 protein encoded by the zmm28 gene is endogenous to maize. DP202216 maize was genetically modified to increase and extend expression of the zmm28 gene relative to native zmm28 gene expression, resulting in plants with enhanced grain yield potential. Evaluation of the history of safe use (HOSU) is one component of the safety assessment framework for a newly expressed protein in a GM crop. The deduced amino acid sequence of the introduced ZMM28 protein in DP202216 maize is identical to the ZMM28 protein in nonmodified conventional maize. The ZMM28 protein has also been found in selected varieties of sweet corn kernels, and closely related proteins are found in other commonly consumed food crops. Concentrations of the ZMM28 protein in event DP202216 maize, conventional maize, and sweet corn are reported. This information supports, in part, the evaluation of HOSU, which can be leveraged in the safety assessment of the ZMM28 protein. Additional studies will be considered in the food and feed safety assessment of the DP202216 maize event.


Assuntos
Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Zea mays/química , Sequência de Aminoácidos , Qualidade de Produtos para o Consumidor , Inocuidade dos Alimentos , Alimentos Geneticamente Modificados , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Zea mays/genética , Zea mays/metabolismo
12.
Plant Cell Rep ; 38(8): 927-936, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147728

RESUMO

KEY MESSAGE: A new anthocyanin biosynthesis transcription factor PdMYB118, which could be used for the genetic engineering of colorful tree species, was indentified from a red leaf mutant of Populus deltoids. In higher plants, the biosynthesis of anthocyanins is regulated by several classes of transcription factors (TFs), including R2R3-MYB, bHLH and WD-repeat proteins. In this work, we isolated an MYB gene regulating anthocyanin biosynthesis from a red leaf mutant of Populus deltoids, which accumulated more anthocyanins in the leaves and showed higher expression levels of anthocyanin biosynthesis genes than did the wild type. Gene expression analyses of all TFs regulating anthocyanin biosynthesis demonstrated that only a MYB118 homologous gene, PdMYB118, was up-regulated in the mutant compared with the wide type. Subcellular localization analyses in poplar leaf mesophyll protoplasts showed that PdMYB118-YFP fusion protein was specifically located in nucleus. When transiently expressed in poplar leaf protoplasts, PdMYB118 specifically promoted the expression of anthocyanidin biosynthesis genes. Dual-luciferase assays revealed that PdMYB118 can directly activate the promoters of these genes. When overexpressed in Shanxin Yang (P. davidiana × P. bolleana), a hybrid clone commercially grown for landscaping in the northern part of China, transgenic plants overexpressing PdMYB118 produced more anthocyanins in the leaves and turned their color into redness when grown in both greenhouse and field. Consistently, transcripts of some important anthocyanidin biosynthesis genes were significantly increased in the leaves of transgenic plants. All these results indicate that PdMYB118 functions as an essential transcription factor regulating anthocyanin biosynthesis in poplar and could be used for the genetic engineering of colorful tree species.


Assuntos
Antocianinas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Mutação/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Populus/genética , Fatores de Transcrição/genética
13.
Pestic Biochem Physiol ; 157: 186-195, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153467

RESUMO

The sugarcane shoot borer Chilo infuscatellus (Snellen) is known for causing severe damage to sugarcane yield in China. Methods have been developed to control this pest, including Cry toxin pesticide and transgenic Bt plants. In order to investigate the molecular mechanism of the Cry toxin binding process and provide a basis for understanding the insect's resistance mechanism, we used a high throughput sequencing platform to perform a de novo transcriptome assembly across different larval developmental stages and analyzed Cry toxin receptors based on our assembled transcripts. We cloned twelve Cry toxin receptor genes including 1 cadherin (Cad), 7 aminopeptidase-Ns (APNs), 3 alkaline phosphatases (ALPs), and 1 ATP-binding cassette transporter subfamily C2 (ABCC2), and three of them with full length. The sublethal dosage of Cry1Ac toxin was applied to sugarcane shoot borer and identified some Cry toxin receptor genes that were significantly induced after 48 h of exposure. Furthermore, quantitative RT-PCR was conducted to detect the expression profiles of these genes. Our transcriptome sequence data provided a valuable molecular resource for further study and the identified Cry toxin receptor data gave insights for improved research into the mechanism of Bt resistance.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Hemolisinas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Saccharum/metabolismo , Animais , Proteínas de Bactérias/genética , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Resistência a Inseticidas/genética , Mariposas , Plantas Geneticamente Modificadas/genética , Saccharum/genética
14.
Plant Mol Biol ; 101(3): 235-255, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254267

RESUMO

KEY MESSAGE: The core set of biosynthetic genes potentially involved in developmental lignification was identified in the model C4 grass Setaria viridis. Lignin has been recognized as a major recalcitrant factor negatively affecting the processing of plant biomass into bioproducts. However, the efficient manipulation of lignin deposition in order to generate optimized crops for the biorefinery requires a fundamental knowledge of several aspects of lignin metabolism, including regulation, biosynthesis and polymerization. The current availability of an annotated genome for the model grass Setaria viridis allows the genome-wide characterization of genes involved in the metabolic pathway leading to the production of monolignols, the main building blocks of lignin. Here we performed a comprehensive study of monolignol biosynthetic genes as an initial step into the characterization of lignin metabolism in S. viridis. A total of 56 genes encoding bona fide enzymes catalyzing the consecutive ten steps of the monolignol biosynthetic pathway were identified in the S. viridis genome. A combination of comparative phylogenetic studies, high-throughput expression analysis and quantitative RT-PCR analysis was further employed to identify the family members potentially involved in developmental lignification. Accordingly, 14 genes clustered with genes from closely related species with a known function in lignification and showed an expression pattern that correlates with lignin deposition. These genes were considered the "core lignin toolbox" responsible for the constitutive, developmental lignification in S. viridis. These results provide the basis for further understanding lignin deposition in C4 grasses and will ultimately allow the validation of biotechnological strategies to produce crops with enhanced processing properties.


Assuntos
Lignina/metabolismo , Poaceae/metabolismo , Biomassa , Vias Biossintéticas , Coenzima A Ligases/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Funções Verossimilhança , Metiltransferases/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Filogenia , Plantas Geneticamente Modificadas/metabolismo , Transcinamato 4-Mono-Oxigenase/metabolismo
15.
Plant Cell Physiol ; 60(8): 1734-1746, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076755

RESUMO

Pentatricopeptide repeat (PPR) proteins play crucial roles in intron splicing, which is important for RNA maturation. Identification of novel PPR protein with the function of intron splicing would help to understand the RNA splicing mechanism. In this study, we identified the maize empty pericarp602 (emp602) mutants, the mature kernels of which showed empty pericarp phenotype. We cloned the Emp602 gene from emp602 mutants and revealed that Emp602 encodes a mitochondrial-localized P-type PPR protein. We further revealed that Emp602 is specific for the cis-splicing of mitochondrial Nad4 intron 1 and intron 3, and mutation of Emp602 led to the loss of mature Nad4 transcripts. The loss of function of Emp602 nearly damaged the assembly and accumulation of complex I and arrested mitochondria formation, which arrested the seed development. The failed assembly of complex I triggers significant upregulation of Aox expression in emp602 mutants. Transcriptome analysis showed that the expression of mitochondrial-related genes, e.g. the genes associated with mitochondrial inner membrane presequence translocase complex and electron carrier activity, were extensively upregulated in emp602 mutant. These results demonstrate that EMP602 functions in the splicing of Nad4 intron 1 and intron 3, and the loss of function of Emp602 arrested maize seed development by disrupting the mitochondria complex I assembly.


Assuntos
Sementes/metabolismo , Zea mays/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Íntrons/genética , Íntrons/fisiologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Processamento de RNA/genética , Processamento de RNA/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Zea mays/genética , Zea mays/crescimento & desenvolvimento
16.
Plant Cell Physiol ; 60(8): 1747-1760, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076768

RESUMO

Artemisinin, the frontline drug against malaria, is a sesquiterpenoid extracted from Artemisia annua. Light has been proposed to play an important role in the activation of artemisinin biosynthesis. Here, we report the basic leucine zipper transcription factor (TF) AaHY5 as a key regulator of light-induced biosynthesis of artemisinin. We show that AaHY5 transcription overlaps with that of artemisinin biosynthesis genes in response to light and in A. annua tissues. Analysis of AaHY5 overexpression and RNAi-suppression lines suggests that AaHY5 is a positive regulator of the expression of artemisinin biosynthesis genes and accumulation of artemisinin. We show that AaHY5 complements the hy5 mutant in Arabidopsis thaliana. Our data further suggest that AaHY5 interacts with AaCOP1, the ubiquitin E3 ligase CONSTITUTIVE PHOTOMORPHOGENIC1 in A. annua. In yeast one-hybrid and transient expression assays, we demonstrate that AaHY5 acts via the TF GLANDULAR TRICHOME-SPECIFIC WRKY 1 (AaGSW1) in artemisinin regulation. In summary, we present a novel regulator of artemisinin gene expression and propose a model in which AaHY5 indirectly controls artemisinin production in response to changing light conditions.


Assuntos
Artemisia annua/metabolismo , Artemisininas/metabolismo , Luz , Artemisia annua/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/efeitos da radiação , Fatores de Transcrição
17.
Int J Mol Sci ; 20(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091755

RESUMO

In this study, we generated transgenic durum wheat cv. Maali overexpressing the wheat plasma membrane aquaporin TdPIP2;1 gene under the control of PrTdPIP2;1 promoter or under the constitutive PrCaMV35S promoter. Histochemical analysis of the fusion PrTdPIP2;1::TdPIP2;1::GusA in wheat plants showed that the ß-glucuronidase (GUS) activity was detected in the leaves, stems and roots of stably transformed wheat T3 plants. Our results showed that transgenic wheat lines overexpressing the TdPIP2;1 gene exhibited improved germination rates and biomass production and retained low Na+ and high K+ concentrations in their shoots under high salt and osmotic stress conditions. In a long-term study under greenhouse conditions on salt or drought stress, transgenic TdPIP2;1 lines produced filled grains, whereas wild-type (WT) plants either died at the vegetative stage under salt stress or showed drastically reduced grain filling under drought stress. Performing real time RT-PCR experiments on wheat plants transformed with the fusion PrTdPIP2;1::GusA, we showed an increase in the accumulation of GusA transcripts in the roots of plants challenged with salt and drought stress. Study of the antioxidant defence system in transgenic wheat TdPIP2;1 lines showed that these lines induced the antioxidative enzymes Catalase (CAT) and Superoxide dismutase (SOD) activities more efficiently than the WT plants, which is associated with lower malondialdehyde and hydrogen peroxide contents. Taken together, these results indicate the high potential of the TdPIP2;1 gene for reducing water evaporation from leaves (water loss) in response to water deficit through the lowering of transpiration per unit leaf area (stomatal conductance) and engineering effective drought and salt tolerance in transgenic TdPIP2;1 lines.


Assuntos
Aquaporinas/genética , Secas , Proteínas de Plantas/genética , Tolerância ao Sal , Triticum/genética , Aquaporinas/metabolismo , Catalase/genética , Catalase/metabolismo , Germinação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Triticum/metabolismo , Triticum/fisiologia , Regulação para Cima
18.
Plant Cell Physiol ; 60(8): 1842-1854, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31135032

RESUMO

Cytokinins are known to regulate various physiological events in plants. Cytokinin signaling is mediated by the phosphorelay system, one of the most ancient mechanisms controlling hormonal pathways in plants. The liverwort Marchantia polymorpha possesses all components necessary for cytokinin signaling; however, whether they respond to cytokinins and how the signaling is fine-tuned remain largely unknown. Here, we report cytokinin function in Marchantia development and organ formation. Our measurement of cytokinin species revealed that cis-zeatin is the most abundant cytokinin in Marchantia. We reduced the endogenous cytokinin level by overexpressing the gene for cytokinin oxidase, MpCKX, which inactivates cytokinins, and generated overexpression and knockout lines for type-A (MpRRA) and type-B (MpRRB) response regulators to manipulate the signaling. The overexpression lines of MpCKX and MpRRA, and the knockout lines of MpRRB, shared phenotypes such as inhibition of gemma cup formation, enhanced rhizoid formation and hyponastic thallus growth. Conversely, the knockout lines of MpRRA produced more gemma cups and exhibited epinastic thallus growth. MpRRA expression was elevated by cytokinin treatment and reduced by knocking out MpRRB, suggesting that MpRRA is upregulated by the MpRRB-mediated cytokinin signaling, which is antagonized by MpRRA. Our findings indicate that when plants moved onto land they already deployed the negative feedback loop of cytokinin signaling, which has an indispensable role in organogenesis.


Assuntos
Citocininas/metabolismo , Marchantia/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Marchantia/genética , Organogênese Vegetal/genética , Organogênese Vegetal/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
19.
Plant Cell Rep ; 38(8): 915-926, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31037366

RESUMO

KEY MESSAGE: Transgenic callus and roots of ice plant with altered SnRK1 function were established using Agrobacterium-mediated transformation. The role of McSnRK1 in controlling Na+ influx and Na/K ratio was demonstrated. SnRK1 kinases (SNF1-related protein kinase1) control metabolic adaptation during energy deprivation and regulate protective mechanisms against environmental stress. Yeast SNF1 activates a P-type ATPase, the Na+ exclusion pump, under glucose starvation. The involvement of plant SnRK1 in salt stress response is largely unknown. We previously identified a salt-induced McSnRK1 in the halophyte ice plant (Mesembryanthemum crystallinum). In the current study, the function of McSnRK1 in salt tolerance was analyzed in transgenic cultured cells and roots of ice plant. Ice plant callus constitutively expressed a high level of McSnRK1 and introducing the full-length McSnRK1 did not alter the Na/K ratio at 24 h after 200 mM NaCl treatment. However, interfering with McSnRK1 activity by introducing a truncate McSnRK1 to produce a dominant-negative form of McSnRK1 increased cellular Na+ accumulation and Na/K ratio. As a result, the growth of cultured cells diminished under salt treatment. Hydroponically grown ice plants with roots expressing full-length McSnRK1 had better growth and lowered Na/K ratio compared to the wild-type or vector-only plants. Roots expressing a truncate McSnRK1 had reduced growth and high Na/K ratio under 400 mM NaCl treatment. The changes in Na/K ratio in transgenic cells and whole plants demonstrated the function of SnRK1 in controlling Na+ flux and maintaining Na/K homeostasis under salinity. The Agrobacterium-mediated transformation system could be a versatile tool for functional analysis of genes involved in salt tolerance in the ice plant.


Assuntos
Mesembryanthemum/enzimologia , Mesembryanthemum/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Homeostase , Mesembryanthemum/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Potássio/metabolismo , Proteínas Serina-Treonina Quinases/genética , Plantas Tolerantes a Sal/efeitos dos fármacos , Plantas Tolerantes a Sal/genética , Sódio/metabolismo , Cloreto de Sódio/farmacologia
20.
J Agric Food Chem ; 67(21): 5997-6006, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31056906

RESUMO

A fluoride export gene ( CsFEX) was newly found and isolated from Camellia sinensis, and its functions in detoxifying F were investigated in transgenic Escherichia coli and Arabidopsis thaliana. CsFEX contains two crcB domains, which is the typical structure in plants. The expression of CsFEX in C. sinensis is tissue-specific and related to maturity of leaves, and its expression is significantly induced by F treatments in different tissues of C. sinensis, particularly in leaves. Additionally, the growth of C. sinensis, E. coli, and A. thaliana can all be inhibited by F treatment. However, the growth of CsFEX-overexpression E. coli was increased with lower F content under F treatment compared to the control. Similarly, the germination and growth of CsFEX-overexpression A. thaliana were enhanced with lower F content under F treatment compared to the wild type. CsFEX relieves F toxicity in the transgenic E. coli and A. thaliana by alleviating F accumulation.


Assuntos
Arabidopsis/metabolismo , Camellia sinensis/genética , Escherichia coli/metabolismo , Fluoretos/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Transporte Biológico , Camellia sinensis/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Fluoretos/toxicidade , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética
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