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1.
Plant Cell ; 31(11): 2711-2733, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31484683

RESUMO

Plant surface waxes form an outer barrier that protects the plant from many forms of environmental stress. The deposition of cuticular waxes on the plant surface is regulated by external environmental changes, including light and dark cycles. However, the underlying molecular mechanisms controlling light regulation of wax production are still poorly understood, especially at the posttranscriptional level. In this paper, we report the regulation of cuticular wax production by the miR156-SPL9 (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9) module in Arabidopsis (Arabidopsis thaliana). When compared with wild-type plants, miR156 and SPL9 mutants showed significantly altered cuticular wax amounts in both stems and leaves. Furthermore, it was found that SPL9 positively regulates gene expression of the alkane-forming enzyme ECERIFERUM1 (CER1), as well as the primary (1-) alcohol-forming enzyme ECERIFERUM4 (CER4), to enhance alkane and 1-alcohol synthesis, respectively. Our results indicate that complex formation of SPL9 with a negative regulator of wax synthesis, DEWAX, will hamper SPL9 DNA binding ability, possibly by interfering with SPL9 homodimerization. Combined with their diurnal gene and protein expressions, this dynamic repression-activation transcriptional module defines a dynamic mechanism that may allow plants to optimize wax synthesis during daily cycles. These findings provide a regulatory framework for environmental signal integration in the regulation of wax synthesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epiderme Vegetal/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Ceras/metabolismo , Aldeído Oxirredutases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Epiderme Vegetal/genética , Plantas Geneticamente Modificadas , Estresse Fisiológico , Transativadores/genética
2.
Plant Cell Physiol ; 59(10): 1990-2003, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137600

RESUMO

The tung tree (Vernicia fordii) is one of only a few plant species that produces high oil-yielding seeds rich in α-eleostearic acid (α-ESA, 18:3Δ9cis, 11trans, 13trans), a conjugated trienoic fatty acid with valuable industrial and medical properties. Previous attempts have been made to engineer tung oil biosynthesis in transgenic oilseed crops, but these efforts have met with limited success. Here we present a high-quality genome assembly and developing seed transcriptomic data set for this species. Whole-genome shotgun sequencing generated 176 Gb of genome sequence data used to create a final assembled sequence 1,176,320 kb in size, with a scaffold N50 size of >474 kb, and containing approximately 47,000 protein-coding genes. Genomic and transcriptomic data revealed full-length candidate genes for most of the known and suspected reactions that are necessary for fatty acid desaturation/conjugation, acyl editing and triacylglycerol biosynthesis. Seed transcriptomic analyses also revealed features unique to tung tree, including unusual transcriptional profiles of fatty acid biosynthetic genes, and co-ordinated (and seemingly paradoxical) simultaneous up-regulation of both fatty acid ß-oxidation and triacylglycerol biosynthesis in mid-development seeds. The precise temporal control of the expression patterns for these two pathways may account for α-ESA enrichment in tung seeds, while controlling the levels of potentially toxic by-products. Deeper understanding of these processes may open doors to the design of engineered oilseeds containing high levels of α-ESA.


Assuntos
Genoma de Planta/genética , Ácidos Linolênicos/metabolismo , Sementes/metabolismo , Transcriptoma/genética , Triglicerídeos/biossíntese , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia
3.
Plant Physiol ; 173(2): 1109-1124, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28069670

RESUMO

We report n-6 monounsaturated primary alcohols (C26:1, C28:1, and C30:1 homologs) in the cuticular waxes of Arabidopsis (Arabidopsis thaliana) inflorescence stem, a class of wax not previously reported in Arabidopsis. The Arabidopsis cer17 mutant was completely deficient in these monounsaturated alcohols, and CER17 was found to encode a predicted ACYL-COENZYME A DESATURASE LIKE4 (ADS4). Studies of the Arabidopsis cer4 mutant and yeast variously expressing CER4 (a predicted fatty acyl-CoA reductase) with CER17/ADS4, demonstrated CER4's principal role in synthesis of these monounsaturated alcohols. Besides unsaturated alcohol deficiency, cer17 mutants exhibited a thickened and irregular cuticle ultrastructure and increased amounts of cutin monomers. Although unsaturated alcohols were absent throughout the cer17 stem, the mutation's effects on cutin monomers and cuticle ultrastructure were much more severe in distal than basal stems, consistent with observations that the CER17/ADS4 transcript was much more abundant in distal than basal stems. Furthermore, distal but not basal stems of a double mutant deficient for both CER17/ADS4 and LONG-CHAIN ACYL-COA SYNTHETASE1 produced even more cutin monomers and a thicker and more disorganized cuticle ultrastructure and higher cuticle permeability than observed for wild type or either mutant parent, indicating a dramatic genetic interaction on conversion of very long chain acyl-CoA precursors. These results provide evidence that CER17/ADS4 performs n-6 desaturation of very long chain acyl-CoAs in both distal and basal stems and has a major function associated with governing cutin monomer amounts primarily in the distal segments of the inflorescence stem.


Assuntos
Álcoois/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Ácidos Graxos Dessaturases/metabolismo , Lipídeos de Membrana/metabolismo , Ceras/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Cromatografia Gasosa , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Epistasia Genética , Ácidos Graxos Dessaturases/química , Ácidos Graxos Dessaturases/genética , Regulação da Expressão Gênica de Plantas , Inflorescência/metabolismo , Mutação/genética , Epiderme Vegetal/citologia , Epiderme Vegetal/metabolismo , Epiderme Vegetal/ultraestrutura , Caules de Planta/metabolismo , Caules de Planta/ultraestrutura , Transporte Proteico
4.
Proc Natl Acad Sci U S A ; 112(37): E5123-32, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26324896

RESUMO

Seed weight (SW), which is one of the three major factors influencing grain yield, has been widely accepted as a complex trait that is controlled by polygenes, particularly in polyploid crops. Brassica napus L., which is the second leading crop source for vegetable oil around the world, is a tetraploid (4×) species. In the present study, we identified a major quantitative trait locus (QTL) on chromosome A9 of rapeseed in which the genes for SW and silique length (SL) were colocated. By fine mapping and association analysis, we uncovered a 165-bp deletion in the auxin-response factor 18 (ARF18) gene associated with increased SW and SL. ARF18 encodes an auxin-response factor and shows inhibitory activity on downstream auxin genes. This 55-aa deletion prevents ARF18 from forming homodimers, in turn resulting in the loss of binding activity. Furthermore, reciprocal crossing has shown that this QTL affects SW by maternal effects. Transcription analysis has shown that ARF18 regulates cell growth in the silique wall by acting via an auxin-response pathway. Together, our results suggest that ARF18 regulates silique wall development and determines SW via maternal regulation. In addition, our study reveals the first (to our knowledge) QTL in rapeseed and may provide insights into gene cloning involving polyploid crops.


Assuntos
Brassica napus/genética , Brassica rapa/genética , Proteínas de Plantas/fisiologia , Sementes/fisiologia , Fatores de Transcrição/fisiologia , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , Brassica napus/fisiologia , Brassica rapa/fisiologia , Primers do DNA , Deleção de Genes , Ligação Genética , Marcadores Genéticos , Íntrons , Dados de Sequência Molecular , Mutação , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Poliploidia , Locos de Características Quantitativas , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Fatores de Transcrição/genética , Transcriptoma , Transgenes
5.
Biochem Biophys Res Commun ; 487(2): 362-367, 2017 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-28414129

RESUMO

The Cytosolic Protein Response (CPR) in the cytosol and the Unfolded Protein Response (UPR) and ER-associated degradation (ERAD) in the endoplasmic reticulum are major pathways of the cellular proteostasis network. However, despite years of effort, how these protein quality control systems coordinated in vivo remains largely unknown, particularly in plants. In this study, the roles of two evolutionarily conserved ERAD pathways (DOA10 and HRD1) in heat stress response were investigated through reverse genetic approaches in Arabidopsis. Phenotypic analysis of the mutants showed that the two ERAD pathways additively play negative roles in heat tolerance, which was demonstrated by higher survival rate and lower electrolyte leakage in the loss of function mutants compared to the wild type plants. Importantly, gene expression analysis revealed that the mutant plants showed elevated transcriptional regulation of several downstream genes, including those encoding CPR and UPR marker genes, under both basal and heat stress conditions. Finally, multiple components of ERAD genes exhibited rapid response to increasing temperature. Taken together, our data not only unravels key insights into the crosstalk between different protein quality control processes, but also provides candidate genes to genetically improve plant heat tolerance in the future.


Assuntos
Arabidopsis/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Degradação Associada com o Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/fisiologia , Resposta ao Choque Térmico/fisiologia , Termotolerância/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Transdução de Sinais/fisiologia
6.
Plant Physiol ; 168(1): 343-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25818700

RESUMO

The development of the plant root system is highly plastic, which allows the plant to adapt to various environmental stresses. Salt stress inhibits root elongation by reducing the size of the root meristem. However, the mechanism underlying this process remains unclear. In this study, we explored whether and how auxin and nitric oxide (NO) are involved in salt-mediated inhibition of root meristem growth in Arabidopsis (Arabidopsis thaliana) using physiological, pharmacological, and genetic approaches. We found that salt stress significantly reduced root meristem size by down-regulating the expression of PINFORMED (PIN) genes, thereby reducing auxin levels. In addition, salt stress promoted AUXIN RESISTANT3 (AXR3)/INDOLE-3-ACETIC ACID17 (IAA17) stabilization, which repressed auxin signaling during this process. Furthermore, salt stress stimulated NO accumulation, whereas blocking NO production with the inhibitor N(ω)-nitro-l-arginine-methylester compromised the salt-mediated reduction of root meristem size, PIN down-regulation, and stabilization of AXR3/IAA17, indicating that NO is involved in salt-mediated inhibition of root meristem growth. Taken together, these findings suggest that salt stress inhibits root meristem growth by repressing PIN expression (thereby reducing auxin levels) and stabilizing IAA17 (thereby repressing auxin signaling) via increasing NO levels.


Assuntos
Arabidopsis/anatomia & histologia , Arabidopsis/fisiologia , Ácidos Indolacéticos/metabolismo , Meristema/anatomia & histologia , Óxido Nítrico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Meristema/efeitos dos fármacos , Meristema/genética , Tamanho do Órgão/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos
7.
Plant Physiol ; 165(3): 1255-1268, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24812105

RESUMO

The ECERIFERUM9 (CER9) gene encodes a putative E3 ubiquitin ligase that functions in cuticle biosynthesis and the maintenance of plant water status. Here, we found that CER9 is also involved in abscisic acid (ABA) signaling in seeds and young seedlings of Arabidopsis (Arabidopsis thaliana). The germinated embryos of the mutants exhibited enhanced sensitivity to ABA during the transition from reversible dormancy to determinate seedling growth. Expression of the CER9 gene is closely related to ABA levels and displays a similar pattern to that of ABSCISIC ACID-INSENSITIVE5 (ABI5), which encodes a positive regulator of ABA responses in seeds. cer9 mutant seeds exhibited delayed germination that is independent of seed coat permeability. Quantitative proteomic analyses showed that cer9 seeds had a protein profile similar to that of the wild type treated with ABA. Transcriptomics analyses revealed that genes involved in ABA biosynthesis or signaling pathways were differentially regulated in cer9 seeds. Consistent with this, high levels of ABA were detected in dry seeds of cer9. Blocking ABA biosynthesis by fluridone treatment or by combining an ABA-deficient mutation with cer9 attenuated the phenotypes of cer9. Whereas introduction of the abi1-1, abi3-1, or abi4-103 mutation could completely eliminate the ABA hypersensitivity of cer9, introduction of abi5 resulted only in partial suppression. These results indicate that CER9 is a novel negative regulator of ABA biosynthesis and the ABA signaling pathway during seed germination.

8.
Plant Cell Rep ; 33(7): 1091-108, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24682522

RESUMO

KEY MESSAGE: Cosuppression of an Arabidopsis Rubisco small subunit gene RBCS3B at Arabidopsis resulted in albino or pale green phenotypes which were caused by ROS accumulation As the most abundant protein on Earth, Rubisco has received much attention in the past decades. Even so, its function is still not understood thoroughly. In this paper, four Arabidopsis transgenic lines (RBCS3B-7, 18, 33, and 35) with albino or pale green phenotypes were obtained by transformation with a construct driving expression of sense RBCS3B, a Rubisco small subunit gene. The phenotypes produced in these transgenic lines were found to be caused by cosuppression. Among these lines, RBCS3B-7 displayed the most severe phenotypes including reduced height, developmental arrest and plant mortality before flowering when grown under normal light on soil. Chloroplast numbers in mesophyll cells were decreased compared to WT, and stacked thylakoids of chloroplasts were broken down gradually in RBCS3B-7 throughout development. In addition, the RBCS3B-7 line was light sensitive, and PSII activity measurement revealed that RBCS3B-7 suffered severe photoinhibition, even under normal light. We found that photoinhibition was due to accumulation of ROS, which accelerated photodamage of PSII and inhibited the repair of PSII in RBCS3B-7.


Assuntos
Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Espécies Reativas de Oxigênio/metabolismo , Ribulose-Bifosfato Carboxilase/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/genética , Luz , Células do Mesofilo/metabolismo , Células do Mesofilo/ultraestrutura , Dados de Sequência Molecular , Fenótipo , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Ribulose-Bifosfato Carboxilase/metabolismo , Solo , Tilacoides/metabolismo
9.
Plant J ; 69(3): 432-44, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21954986

RESUMO

Seed oil content is an important agronomic trait in rapeseed. However, our understanding of the regulatory processes controlling oil accumulation is still limited. Using two rapeseed lines (zy036 and 51070) with contrasting oil content, we found that maternal genotype greatly affects seed oil content. Genetic and physiological evidence indicated that difference in the local and tissue-specific photosynthetic activity in the silique wall (a maternal tissue) was responsible for the different seed oil contents. This effect was mimicked by in planta manipulation of silique wall photosynthesis. Furthermore, the starch content and expression of the important lipid synthesis regulatory gene WRINKLED1 in developing seeds were linked with silique wall photosynthetic activity. 454 pyrosequencing was performed to explore the possible molecular mechanism for the difference in silique wall photosynthesis between zy036 and 51070. Interestingly, the results suggested that photosynthesis-related genes were over-represented in both total silique wall expressed genes and genes that were differentially expressed between genotypes. A potential regulatory mechanism for elevated photosynthesis in the zy036 silique wall is proposed on the basis of knowledge from Arabidopsis. Differentially expressed ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)-related genes were used for further investigations. Oil content correlated closely with BnRBCS1A expression levels and Rubisco activities in the silique wall, but not in the leaf. Taken together, our results highlight an important role of silique wall photosynthesis in the regulation of seed oil content in terms of maternal effects.


Assuntos
Brassica napus/genética , Flores/fisiologia , Fotossíntese/fisiologia , Óleos de Plantas/química , Sementes/química , Brassica napus/fisiologia , Etiquetas de Sequências Expressas , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genes de Plantas , Genótipo , RNA de Plantas/genética , Ribulose-Bifosfato Carboxilase/metabolismo , Análise de Sequência de DNA , Amido/biossíntese , Transcriptoma
10.
Plant Cell Physiol ; 53(2): 344-57, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22186181

RESUMO

Nitric oxide (NO) plays essential roles in many physiological and developmental processes in plants, including biotic and abiotic stresses, which have adverse effects on agricultural production. However, due to the lack of findings regarding nitric oxide synthase (NOS), many difficulties arise in investigating the physiological roles of NO in vivo and thus its utilization for genetic engineering. Here, to explore the possibility of manipulating the endogenous NO level, rat neuronal NOS (nNOS) was expressed in Arabidopsis thaliana. The 35S::nNOS plants showed higher NOS activity and accumulation of NO using the fluorescent probe 3-amino, 4-aminomethyl-2', 7'-difluorescein, diacetate (DAF-FM DA) assay and the hemoglobin assay. Compared with the wild type, the 35S::nNOS plants displayed improved salt and drought tolerance, which was further confirmed by changes in physiological parameters including reduced water loss rate, reduced stomatal aperture, and altered proline and malondialdehyde content. Quantitative real-time PCR analyses revealed that the expression of several stress-regulated genes was up-regulated in the transgenic lines. Furthermore, the transgenic lines also showed enhanced disease resistance against Pseudomonas syringae pv. tomato (Pst) DC3000 by activating the expression of defense-related genes. In addition, we found that the 35S::nNOS lines flowered late by regulating the expression of CO, FLC and LFY genes. Together, these results demonstrated that it is a useful strategy to exploit the roles of plant NO in various processes by the expression of rat nNOS. The approach may also be useful for genetic engineering of crops with increased environmental adaptations.


Assuntos
Arabidopsis/metabolismo , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico/biossíntese , Estresse Fisiológico , Animais , Arabidopsis/genética , Arabidopsis/fisiologia , Resistência à Doença , Secas , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Engenharia Genética , Peroxidação de Lipídeos , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Prolina/análise , Pseudomonas syringae/patogenicidade , Ratos , Cloreto de Sódio/farmacologia
11.
J Exp Bot ; 63(10): 3727-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22442419

RESUMO

Seed yield and oil content are two important agricultural characteristics in oil crop breeding, and a lot of functional gene research is being concentrated on increasing these factors. In this study, by differential gene expression analyses between rapeseed lines (zy036 and 51070) which exhibit different levels of seed oil production, BnGRF2 (Brassica napus growth-regulating factor 2-like gene) was identified in the high oil-producing line zy036. To elucidate the possible roles of BnGRF2 in seed oil production, the cDNA sequences of the rapeseed GRF2 gene were isolated. The Blastn result showed that rapeseed contained BnGRF2a/2b which were located in the A genome (A1 and A3) and C genome (C1 and C6), respectively, and the dominantly expressed gene BnGRF2a was chosen for transgenic research. Analysis of 35S-BnGRF2a transgenic Arabidopsis showed that overexpressed BnGRF2a resulted in an increase in seed oil production of >50%. Moreover, BnGRF2a also induced a >20% enlargement in extended leaves and >40% improvement in photosynthetic efficiency because of an increase in the chlorophyll content. Furthermore, transcriptome analyses indicated that some genes associated with cell proliferation, photosynthesis, and oil synthesis were up-regulated, which revealed that cell number and plant photosynthesis contributed to the increased seed weight and oil content. Because of less efficient self-fertilization induced by the longer pistil in the 35S-BnGRF2a transgenic line, Napin-BnGRF2a transgenic lines were further used to identify the function of BnGRF2, and the results showed that seed oil production also could increase >40% compared with the wild-type control. The results suggest that improvement to economically important characteristics in oil crops may be achieved by manipulation of the GRF2 expression level.


Assuntos
Brassica napus/metabolismo , Fotossíntese , Óleos de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Sementes/citologia , Regulação para Cima , Sequência de Aminoácidos , Brassica napus/química , Brassica napus/citologia , Brassica napus/genética , Contagem de Células , Proliferação de Células , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Sementes/química , Sementes/genética , Sementes/metabolismo , Alinhamento de Sequência
12.
Materials (Basel) ; 15(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36295351

RESUMO

The construction of subways, hydroelectric stations and water substations is exposed to stray currents, which can accelerate concrete corrosion. The influence of stray currents on reinforced concrete structures is unclear. In this paper, the influence of concrete strength grade, reinforcement diameter and stray current intensity on the extent of reinforcement corrosion and calcium ion dissolution were investigated, and the damage of reinforcement and calcium ion corrosion to concrete strength was investigated by simulating a stray current environment and conducting an electrified acceleration test. The test results show that the higher the strength grade of concrete, the lower the stray current intensity and the smaller the corrosion rate and calcium ion dissolution rate of reinforcement; with the increase in the diameter of reinforcement the corrosion rate decreases, but the calcium ion dissolution rate is not affected by reinforcement diameter. The damage effect of reinforcement corrosion on concrete compressive strength is more obvious than that of calcium ion corrosion.

13.
Hortic Res ; 9: uhac208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467268

RESUMO

Cissus is the largest genus in Vitaceae and is mainly distributed in the tropics and subtropics. Crassulacean acid metabolism (CAM), a photosynthetic adaptation to the occurrence of succulent leaves or stems, indicates that convergent evolution occurred in response to drought stress during species radiation. Here we provide the chromosomal level assembly of Cissus rotundifolia (an endemic species in Eastern Africa) and a genome-wide comparison with grape to understand genome divergence within an ancient eudicot family. Extensive transcriptome data were produced to illustrate the genetics underpinning C. rotundifolia's ecological adaption to seasonal aridity. The modern karyotype and smaller genome of C. rotundifolia (n = 12, 350.69 Mb/1C), which lack further whole-genome duplication, were mainly derived from gross chromosomal rearrangements such as fusions and segmental duplications, and were sculpted by a very recent burst of retrotransposon activity. Bias in local gene amplification contributed to its remarkable functional divergence from grape, and the specific proliferated genes associated with abiotic and biotic responses (e.g. HSP-20, NBS-LRR) enabled C. rotundifolia to survive in a hostile environment. Reorganization of existing enzymes of CAM characterized as diurnal expression patterns of relevant genes further confer the ability to thrive in dry savannas.

14.
J Clin Gastroenterol ; 45(7): 643-50, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21301360

RESUMO

OBJECTIVE: This study was designed to determine whether a transjugular intrahepatic portosystemic shunt (TIPS) combined with embolotherapy was superior to TIPS alone. METHODS: Seventy-nine patients were included in the study (43 in the TIPS and embolotherapy group and 36 in the TIPS alone group). Embolotherapy was performed after TIPS using coils and a tissue adhesive agent. The portosystemic pressure gradient (PPG) after TIPS was lower than 12 mm Hg in all patients. Multivariate analyses were performed using a Cox regression model, and the probabilities of survival and rebleeding were estimated with the Kaplan-Meier method. RESULTS: Baseline patient survey data showed similar distributions in both groups. The mean follow-up time was 45.6 months (range: 1 to 85.6 mo). There were no significant differences in the incidences of rebleeding (P=0.889), stent revision (P=0.728), encephalopathy (P=0.728), the cumulative survival rate (P=0.552), or the probability of being free of rebleeding (P=0.806) between the 2 groups. Of 9 patients with rebleeding after TIPS plus embolotherapy, 7 had a history of esophageal variceal bleeding and 2 had gastric variceal bleeding. Of 8 patients with rebleeding after TIPS alone, 4 had a history of esophageal variceal bleeding and 4 had gastric variceal bleeding (P=0.247). Multivariate analysis showed that PPG after TIPS was an independent predictor of rebleeding (P=0.036). Age and Model of End-stage Liver Disease score were independent predictors of survival (P=0.048 and 0.037). CONCLUSIONS: The results suggest that TIPS with embolotherapy cannot reduce the risk of rebleeding if PPG is less than 12 mm Hg after TIPS. PPG after TIPS is an independent predictor of rebleeding.


Assuntos
Embolização Terapêutica/métodos , Cirrose Hepática/cirurgia , Cirrose Hepática/terapia , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Adulto , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Varizes Esofágicas e Gástricas/terapia , Feminino , Hemorragia Gastrointestinal/complicações , Hemorragia Gastrointestinal/cirurgia , Hemorragia Gastrointestinal/terapia , Humanos , Hipertensão Portal/cirurgia , Hipertensão Portal/terapia , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
15.
Plant Cell Rep ; 30(8): 1533-40, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21461604

RESUMO

Pyruvate dehydrogenase kinase (PDK) is a negative regulator of the mitochondrial pyruvate dehydrogenase complex (mtPDC), which plays a key role in intermediary metabolism. In this study, a 1,490-bp PDK in Brassica napus (BnPDK1) was isolated and cloned from Brassica cDNA library. BnPDK1 has an 1,104 open reading frame encoding 367 amino acids. Genomic DNA gel blot analysis result indicated that BnPDK1 is a multi-copy gene. RNA gel blot analysis and RNA in situ hybridization were used to determine the expression of BnPDK1 in different organs. BnPDK1 gene was ubiquitously expressed in almost all the tissues tested, having the highest expression in the stamen and the young silique. Over-expression of BnPDK1 in transgenic Arabidopsis lines would repress the PDC activity, and resulted in the decrease of seed oil content and leaf photosynthesis. These results implied that BnPDK1 was involved in the regulation of fatty acid biosynthesis in developing seeds.


Assuntos
Brassica napus/genética , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/genética , Brassica napus/enzimologia , Clonagem Molecular , Ácidos Graxos/biossíntese , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteínas Serina-Treonina Quinases/genética , Piruvato Desidrogenase Quinase de Transferência de Acetil , RNA de Plantas/genética , Sementes/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-33859707

RESUMO

The effect of perioperative acupuncture on accelerating gastrointestinal function recovery has been reported in colorectal surgery and distal gastrectomy (Billroth-II). However, the evidence in pancreatectomy and other gastrectomy is still limited. A prospective, randomized controlled trial was conducted between May 2018 and August 2019. Consecutive patients undergoing pancreatectomy or gastrectomy in our hospital were randomly assigned to the electroacupuncture (EA) group and the control group. The patients in the EA group received transcutaneous EA on Bai-hui (GV20), Nei-guan (PC6), Tian-shu (ST25), and Zu-san-li (ST36) once a day in the afternoon, and the control group received sham EA. Primary outcomes were the time to first flatus and time to first defecation. In total, 461 patients were randomly assigned to the groups, and 385 were analyzed finally (EA group, n = 201; control group, n = 184). Time to first flatus (3.0 ± 0.7 vs 4.2 ± 1.0, P < 0.001) and first defecation (4.2 ± 0.9 vs 5.4 ± 1.2, P < 0.001) in the EA group were significantly shorter than those in the control group. Of patients undergoing pancreatectomy, those undergoing pancreaticoduodenectomy and intraoperative radiation therapy (IORT) surgery benefitted from EA in time to first flatus (P < 0.001) and first defecation (P < 0.001), while those undergoing distal pancreatectomy did not (P flatus=0.157, P defecation=0.007) completely. Of patients undergoing gastrectomy, those undergoing total gastrectomy and distal gastrectomy (Billroth-II) benefitted from EA (P < 0.001), as did those undergoing proximal gastrectomy (P=0.015). Patients undergoing distal gastrectomy (Billroth-I) benefitted from EA in time to first defecation (P=0.012) but not flatus (P=0.051). The time of parenteral nutrition, hospital stay, and time to first independent walk in the EA group were shorter than those in the control group. No severe EA complications were reported. EA was safe and effective in accelerating postoperative gastrointestinal function recovery. Patients undergoing pancreaticoduodenectomy, IORT surgery, total gastrectomy, proximal gastrectomy, or distal gastrectomy (Billroth-II) could benefit from EA. This trial is registered with NCT03291574.

17.
Zhongguo Zhen Jiu ; 40(10): 1119-21, 2020 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-33068357

RESUMO

Professor XUE Li-gong's clinical experiences were summarized in treatment of painful bi syndrome of meridian muscle region with the "unknotting" method of long-round needle. It is believed that painful bi syndrome of meridian muscle region is related chiefly with the invasion of wind, cold and damp pathogens, exertion and traumatic injury. These pathogenic factors induce the "transverse-collateral" entrapment in the local and result in refractory painful bi syndrome of meridian muscle region. The "unknotting" method is adopted with long-round needle, which can either separate bluntly the knotted lesions or cut them sharply. "Taking the painful sites as the points" is the principle of point selection in treatment of meridian muscle disorder. Regarding needling techniques, joint needling, lateral needling and short needling are predominated.


Assuntos
Terapia por Acupuntura/métodos , Meridianos , Músculos/fisiopatologia , Mialgia/terapia , Humanos , Medicina Tradicional Chinesa , Agulhas
18.
Liver Int ; 29(7): 1101-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19386025

RESUMO

BACKGROUND/AIMS: The transjugular intrahepatic portosystemic shunt (TIPS) is technically divided into TIPS through the left branch of the portal vein (TIPS-LBPV) and TIPS through the right branch of the portal vein (TIPS-RBPV). In order to compare their advantages and disadvantages, this randomized, controlled trial was designed to investigate their outcomes in advanced cirrhotic patients. METHODS: Seventy-two patients were randomly placed into TIPS-LBPV (36 patients) and TIPS-RBPV (36 patients, with four failures) groups, and they were prospectively followed for 2 years after TIPS implantation. RESULTS: Patients who underwent the two different kinds of TIPS were balanced during recruitment for this study. The incidences of overall encephalopathy and de novo encephalopathy in the TIPS-LBPV group were significantly lower than that of the TIPS-RBPV group during follow-up (P=0.036 and 0.012 respectively). The incidences of rebleeding or re-intervention and improvement of ascites were similar between groups (P>0.05). Patients undergoing TIPS-RBPV required more rehospitalization and incurred more costs than those who underwent TIPS-LBPV (P=0.030 and 0.039 respectively). There was no significant difference between the two groups in survival based on a survival curve constructed according to the Kaplan-Meier method (P>0.05). CONCLUSION: Patients undergoing TIPS-LBPV had a lower incidence of encephalopathy, less rehospitalization and lower costs after TIPS implantation compared with patients undergoing TIPS-RBPV.


Assuntos
Cirrose Hepática/cirurgia , Veia Porta , Derivação Portossistêmica Transjugular Intra-Hepática/métodos , Adulto , Ascite/etiologia , Ascite/cirurgia , Redução de Custos , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Encefalopatia Hepática/etiologia , Custos Hospitalares , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/complicações , Cirrose Hepática/economia , Cirrose Hepática/mortalidade , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Derivação Portossistêmica Transjugular Intra-Hepática/economia , Derivação Portossistêmica Transjugular Intra-Hepática/mortalidade , Estudos Prospectivos , Recidiva , Reoperação , Medição de Risco , Fatores de Tempo , Resultado do Tratamento
19.
Colloids Surf B Biointerfaces ; 169: 384-394, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29803154

RESUMO

Nanofibers fabricated by electrospinning simulate the extracellular matrix of bone cells and so researchers have taken a keen interest in them for regenerating bone tissue. The aim of this study was to fabricate ideal Zein/PLLA nanofibers by coaxial electrospinning and to load them with bone morphogenetic protein 2 (BMP-2) and dexamethasone (DEX) for dual controlled-release for bone tissue engineering applications. Morphology, surface hydrophilicity and core-shell construction were analyzed by environmental scanning electron microscopy (SEM), water contact angle and transmission electron microscopy (TEM). The properties of the scaffolds were studied in terms of the viability, morphology and osteogenic differentiation of mesenchymal stem cells (MSCs) that had been cultured on nanofiber mats of the Zein/PLLA and were determined using SEM, CCK-8 assay, quantitative ALP staining analysis, quantitative mineral deposition using Alizarin red staining (ARS), immunofluorescence staining and western blot analysis of osteogenic proteins. In vitro studies demonstrated that the biological activity of DEX and BMP-2 was retained in the dual-drug-loaded nanofiber scaffolds. A large quantity of DEX was released in the first three days, while the release of BMP-2 lasted for more than 21 days. In vitro osteogenesis studies showed that the drug-loaded nanofiber scaffolds induced osteogenic differentiation. Furthermore, the dual controlled-release of BMP-2 and DEX enhanced the osteogenic differentiation of MSCs resulting from synergistic effects. Therefore, Zein/PLLA nanofiber scaffolds loaded with BMP-2 and DEX have great potential in bone tissue engineering applications.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Dexametasona/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poliésteres/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Zeína/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Propriedades de Superfície
20.
J Biomater Sci Polym Ed ; 28(18): 2205-2219, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28988518

RESUMO

In this study, we fabricated recombinant human bone morphogenetic protein-2 (rhBMP-2) loaded Poly(lactic-co-glycolic acid) (PLGA) microspheres with core-shell structures and particle sizes ranging from 2.5 to 8 µm by coaxial electrospraying. The manufacturing process of core-shell microspheres by coaxial electrospraying is simpler than that with other methods, and a smaller diameter can be obtained. The microspheres were analyzed by environmental scanning electron microscopy, transmission electron microscopy (TEM), and laser scanning confocal microscopy (LSCM). Moreover, the drug release profiles and degradation of rhBMP-2-loaded PLGA microspheres in vitro were investigated for 21 days and for 7 weeks, respectively. The rhBMP-2 was stabilized by using bovine serum albumin (BSA) to ensure protein activity in the electrospraying process. Fluorescently labeled protein that was loaded into the core-shell PLGA microspheres was verified by LSCM. The distinct layered structure that existed in the manufactured core-shell microspheres can be observed by TEM. Cell Counting Kit-8 (CCK-8) indicated that the core-shell PLGA microspheres loaded with rhBMP-2 have great potential for the treatment of bone defects, for bone regeneration, and in bone tissue engineering.


Assuntos
Proteína Morfogenética Óssea 2/química , Portadores de Fármacos/química , Eletricidade , Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Fator de Crescimento Transformador beta/química , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas Recombinantes/química , Soroalbumina Bovina/química
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