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1.
PLoS One ; 17(7): e0271165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35819940

RESUMO

OBJECTIVE: Theological beliefs play an important role in cultural norms and could impact women's prenatal and postpartum decisions in South Asia, which has a high burden of disease in children and pregnant women. The aim of this study is to identify any associations religion may have in affecting a woman's decision-making ability, and how that in turn affects maternal and child health, at a group level in multiple South Asian countries. STUDY DESIGN: Cross-sectional study utilizing secondary data analysis. METHODS: We used Demographic and Health Surveys (DHS) between 2014 and 2018 in Afghanistan, Bangladesh, India, Maldives, Myanmar, Nepal, and Pakistan. Not every country's survey asked about religion, so we imputed these results based on Census data. We assessed maternal and child health through a composite coverage index (CCI), which accounts for family planning, attendance of a skilled attendant at birth, antenatal care, BCG vaccinations, 3 doses of diphtheria-tetanus-pertussis vaccine, measles vaccine, oral rehydration therapy, and seeking care if the child has pneumonia. The relationship between religion, women's empowerment, and CCI was assessed through linear regression models. RESULTS: The sample included 57,972 mothers who had children aged 12-23 months. CCI is observed to be affected by family income, in addition to religion and country. CCI was higher in Hindus (2.8%, 95% CI: 2.4%, 3.1%) and Buddhists (2.0%, 95% CI: 1.2%, 2.9%) than Muslims. Mother's age, education, income, decision-making autonomy, and attitude towards beatings were all related to CCI. In a model stratified by religion, age, education, and income were significant predictors of CCI for both Muslims and non-Muslims, but were more impactful among Muslims. CONCLUSION: Though multiple imputation had to be used to fill in gaps in religion data, this study demonstrates that maternal and child health outcomes continue to be a concern in South Asia, especially for Muslim women. Given the importance of religious beliefs, utilizing a simple indicator, such as the CCI could be helpful for monitoring these outcomes and provides a tangible first step for communities to address gaps in care resulting from disparities in maternal empowerment.


Assuntos
Islamismo , Avaliação de Resultados em Cuidados de Saúde , Criança , Estudos Transversais , Escolaridade , Feminino , Humanos , Índia , Recém-Nascido , Gravidez
2.
Front Psychiatry ; 13: 825460, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35546944

RESUMO

Background: Depression is one of the greatest public health problems worldwide. The potential benefit of social participation (SP) on mental health has been widely acknowledged. Nevertheless, a few studies have used propensity score matching (PSM) to reduce the influence of data bias and confounding variables. This study explored the effect of social participation on depression among middle-aged and older Chinese persons through a PSM method, considering the frequency, type, and quantity of SP. Effects were compared among different age groups, genders, and places of residence. Methods: The datasets were obtained from the 2018 wave of the China Health and Retirement Longitudinal Study. A total of 9,404 respondents aged 45 and above were included in the study. PSM and ordinary least squares methods were used to estimate the effect of social participation on depression. Results: PSM estimation results showed that SP had a significantly positive effect on decreasing depression scores (p < 0.001) by 0.875-0.898 compared with persons without SP. All types of SP had a significantly positive effect (p < 0.001), and participating in community activities had the largest effect (ß = -1.549 to -1.788, p < 0.001). Higher frequency of participation and more types of SP promoted lower depression scores; subgroup analyses revealed that the promotion effect was significantly greater among women, those aged ≥75 years, and those living in urban areas. Conclusion: PSM indicated that SP could alleviate the depression of middle-aged and older Chinese persons. Targeted measures should be adopted to promote SP and thereby improve mental health and promote healthy and active aging.

3.
BMJ Open ; 12(1): e047753, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017231

RESUMO

OBJECTIVES: This study aimed to examine the prevalence of peritraumatic stress symptoms (PTSSs), perceived threat, social support and factors contributing to clinically significant PTSS among frontline COVID-19 healthcare workers (HCWs) in China. DESIGN AND SETTING: An online survey through self-administered questionnaires was conducted from 18 February to 4 March 2020, during the outbreak of COVID-19. OUTCOMES MEASURES: PTSS was assessed using the post-traumatic stress disorder (PTSD) self-rating scale. Demographic and socioeconomic characteristics, self-reported health, physical/psychological symptoms, perceived threat from frontline work and perceived social support were investigated. Multivariable line regression analysis distinguished factors associated with HCWs' PTSS scores. RESULTS: A total of 676 (58.1%) HCWs have shown clinically significant high levels of PTSS. Only 441 (37.9%) self-reported good health. Most had physical symptom(s) (915 (78.7%)), psychological symptom(s) (906 (77.9%)), inability to vent emotions (284 (24.4%)), emotional exhaustion (666 (57.3%)) and 1037 (89.2%) needed professional respect. Moreover, social support received was less than expected, and the receipt of psychological services/help scored the lowest (3.11±1.73). Combined psychological and physical symptoms, difficulty in releasing tension and venting emotions timely, fear of infection, emotional exhaustion and depersonalisation are significantly associated with PTSS scores among frontline HCWs. Working ≥8 hours, having the senior professional title, self-reported health, enjoying perfect protection and control measures, economic subsidy and control policy on reducing discriminatory practices are negatively correlated with PTSS scores. CONCLUSIONS: During the outbreak of COVID-19, frontline HCWs experienced clinically significant high levels of PTSS and heavy workload, and the emergency resulted in their inadequate psychosocial support. If this is left unchecked, HCWs have a higher risk of developing PTSD. Early detection, identification and person-directed, targeted multidisciplinary interventions should be undertaken to address various influencing factors. Comprehensive measures, including setting up emotional release channels, as well as providing psychological and social support intervention for HCWs globally, are highly recommended.


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , China/epidemiologia , Estudos Transversais , Surtos de Doenças , Pessoal de Saúde , Humanos , SARS-CoV-2 , Transtornos de Estresse Pós-Traumáticos/epidemiologia
4.
Metab Eng ; 62: 20-29, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32841680

RESUMO

Punicic acid (PuA; 18:3Δ9cis,11trans,13cis), a conjugated linolenic acid isomer bearing three conjugated double bonds, is associated with various health benefits and has potential for industrial use. The major nature source of this unusual fatty acid is pomegranate (Punica granatum) seed oil, which contains up to 80% (w/w) of its fatty acids as PuA. Pomegranate seed oil, however, is low yielding with unstable production and thus limits the supply of PuA. Metabolic engineering of established temperate oil crops for PuA production, therefore, has the potential to be a feasible strategy to overcome the limitations associated with sourcing PuA from pomegranate. In this study, the cDNAs encoding a pomegranate fatty acid conjugase and a pomegranate oleate desaturase were co-expressed in canola-type Brassica napus. Transgenic B. napus lines accumulated up to 11% (w/w) of the total fatty acids as PuA in the seed oil, which is the highest level of PuA reported in metabolically engineered oilseed crops so far. Levels of seed oil PuA were stable over two generations and had no negative effects on seed germination. The transgenic B. napus lines with the highest PuA levels contained multiple transgene insertions and the PuA content of B. napus seed oil was correlated with efficiency of oleic acid desaturation and linoleic acid conjugation. In addition, PuA accumulated at lower levels in polar lipids (5.0-6.9%) than triacylglycerol (7.5-10.6%), and more than 60% of triacylglycerol-associated PuA was present at the sn-2 position. This study provides the basis for the commercial production of PuA in transgenic oilseed crops and thus would open new prospects for the application of this unusual fatty acid in health and industry.


Assuntos
Brassica napus , Lythraceae , Brassica napus/genética , Ácidos Linolênicos , Lythraceae/genética , Óleos de Plantas , Sementes/genética
5.
J Biol Chem ; 292(43): 17819-17831, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-28900030

RESUMO

The apparent bottleneck in the accumulation of oil during seed development in some oleaginous plant species is the formation of triacylglycerol (TAG) by the acyl-CoA-dependent acylation of sn-1,2-diacylglycerol catalyzed by diacylglycerol acyltransferase (DGAT, EC 2.3.1.20). Improving DGAT activity using protein engineering could lead to improvements in seed oil yield (e.g. in canola-type Brassica napus). Directed evolution of B. napus DGAT1 (BnaDGAT1) previously revealed that one of the regions where amino acid residue substitutions lead to higher performance in BnaDGAT1 is in the ninth predicted transmembrane domain (PTMD9). In this study, several BnaDGAT1 variants with amino acid residue substitutions in PTMD9 were characterized. Among these enzyme variants, the extent of yeast TAG production was affected by different mechanisms, including increased enzyme activity, increased polypeptide accumulation, and possibly reduced substrate inhibition. The kinetic properties of the BnaDGAT1 variants were affected by the amino acid residue substitutions, and a new kinetic model based on substrate inhibition and sigmoidicity was generated. Based on sequence alignment and further biochemical analysis, the amino acid residue substitutions that conferred increased TAG accumulation were shown to be present in the DGAT1-PTMD9 region of other higher plant species. When amino acid residue substitutions that increased BnaDGAT1 enzyme activity were introduced into recombinant Camelina sativa DGAT1, they also improved enzyme performance. Thus, the knowledge generated from directed evolution of DGAT1 in one plant species can be transferred to other plant species and has potentially broad applications in genetic engineering of oleaginous crops and microorganisms.


Assuntos
Brassica napus/genética , Diacilglicerol O-Aciltransferase , Metabolismo dos Lipídeos , Proteínas de Plantas , Saccharomyces cerevisiae/enzimologia , Substituição de Aminoácidos , Brassica napus/enzimologia , Diacilglicerol O-Aciltransferase/biossíntese , Diacilglicerol O-Aciltransferase/genética , Mutação de Sentido Incorreto , Organismos Geneticamente Modificados/genética , Organismos Geneticamente Modificados/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética
6.
J Exp Bot ; 65(15): 4201-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24821955

RESUMO

The enzyme sn-glycerol-3-phosphate acyltransferase 4 (GPAT4) is involved in the biosynthesis of plant lipid poly-esters. The present study further characterizes the enzymatic activities of three endoplasmic reticulum-bound GPAT4 isoforms of Brassica napus and examines their roles in the development of reproductive organs and the embryo. All three BnGPAT4 isoforms exhibited sn-2 acyltransferase and phosphatase activities with dicarboxylic acid-CoA as acyl donor. When non-substituted acyl-CoA was used as acyl donor, the rate of acylation was considerably lower and phosphatase activity was not manifested. RNA interference (RNAi)-mediated down-regulation of all GPAT4 homologues in B. napus under the control of the napin promoter caused abnormal development of several reproductive organs and reduced seed set. Microscopic examination and reciprocal crosses revealed that both pollen grains and developing embryo sacs of the B. napus gpat4 lines were affected. The gpat4 mature embryos showed decreased cutin content and altered monomer composition. The defective embryo development further affected the oil body morphology, oil content, and fatty acid composition in gpat4 seeds. These results suggest that GPAT4 has a critical role in the development of reproductive organs and the seed of B. napus.


Assuntos
Brassica napus/enzimologia , Flores/crescimento & desenvolvimento , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Sementes/crescimento & desenvolvimento , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , Família Multigênica , Monoéster Fosfórico Hidrolases/metabolismo , Óleos de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/metabolismo
7.
Arch Biochem Biophys ; 554: 55-64, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24841490

RESUMO

Plastidial acyl-acyl carrier protein:sn-glycerol-3-phosphate acyltransferase (GPAT; EC 2.3.1.15) catalyzes the acyl-acyl carrier protein-dependent sn-1 acylation of sn-glycerol 3-phosphate (G3P) to produce lysophosphatic acid. Functional recombinant Erysimum asperum GPAT (EaGPAT), devoid of transit peptide, was produced in yeast. Analysis of the dependence of EaGPAT activity on increasing G3P concentration resulted in a hyperbolic response. EaGPAT exhibited a preference for 18-carbon unsaturated acyl-CoAs. Assays with concentrations of oleoyl-CoA up to 90µM revealed an exponential response to increasing concentrations of acyl donor, and the introduction of increasing concentrations of unlabeled linoleoyl-CoA into the standard reaction mixture resulted in increased incorporation of radiolabeled oleoyl moieties into lysophosphatidic acid. Collectively, the kinetic results suggest that acyl-CoA may act as both substrate and allosteric effector. EaGPAT was also shown to oligomerize to form higher molecular mass multimers, with the monomer and trimer being the predominant forms of the enzyme. Since most allosteric enzyme exhibit quaternary structure, the self-associating properties of EaGPAT are consistent with those of an allosteric enzyme. These results could have important regulatory implications when plastidial GPAT is introduced into a cytoplasmic environment where acyl-CoA is the acyl donor supporting cytoplasmic glycerolipid assembly.


Assuntos
Proteínas de Cloroplastos/química , Proteínas de Cloroplastos/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/química , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Acilação , Regulação Alostérica , Sequência de Bases , Proteínas de Cloroplastos/genética , Clonagem Molecular , DNA de Plantas/genética , Erysimum/enzimologia , Erysimum/genética , Glicerol-3-Fosfato O-Aciltransferase/genética , Glicerofosfatos/metabolismo , Cinética , Filogenia , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
8.
Plant Physiol Biochem ; 58: 142-50, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22809685

RESUMO

A wide range of plant hormones, including gibberellins (GAs) and auxins are known to be involved in regulating seed and fruit growth and development. Changes in ethylene biosynthesis are also associated with seed and fruit development, but ethylene's role in these processes is poorly understood, as is its possible interaction with the other plant hormones. A major complication of investigating ethylene-induced regulation of developmental processes is ethylene's biphasic mode of action. To investigate ethylene's actions and interactions we used a 1-amino-cyclopropane-1-carboxylic acid (ACC) deaminase transgenic canola line. This line evolves significantly less ethylene from its siliques and seeds, relative to plants from a wild type (WT) background. Plants of the transgenic line also had smaller siliques which were associated with reductions in both seed size and seed number. Application of ethephon, a compound that produces ethylene, to plants of the transgenic line restored the WT phenotype for both siliques and seeds. Application of the same dose of ethephon to WT plants diminished both silique and seed development, showing ethylene's biphasic effect and effectively producing the ACC deaminase transgenic phenotype. There were significant decreases in endogenous concentrations of GA(1) and GA(4) and also of indole-3-acetic acid (IAA), between WT seeds and seedless siliques and seeds and siliques from the transgenic line plants. These differences were emphasized during early stages (10-20 days after pollination) of seed and silique development. The above results strongly suggest that ethylene interacts with other endogenous plant hormones in regulating silique and seed development and growth in WT lines of canola.


Assuntos
Brassica napus/metabolismo , Etilenos/metabolismo , Frutas/metabolismo , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/metabolismo , Sementes/metabolismo , Aminoácidos Cíclicos/metabolismo , Brassica napus/efeitos dos fármacos , Brassica napus/crescimento & desenvolvimento , Etilenos/farmacologia , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Fenótipo , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
9.
Plant Mol Biol ; 79(1-2): 61-74, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22351159

RESUMO

Canola (Brassica napus), an agriculturally important oilseed crop, can be significantly affected by diseases such as sclerotinia stem rot, blackleg, and alternaria black spot resulting in significant loss of crop productivity and quality. Cysteine-rich antimicrobial peptides isolated from plants have emerged as a potential resource for protection of plants against phytopathogens. Here we report the significance of an antimicrobial peptide, PmAMP1, isolated from western white pine (Pinus monticola), in providing canola with resistance against multiple phytopathogenic fungi. The cDNA encoding PmAMP1 was successfully incorporated into the genome of B. napus, and it's in planta expression conferred greater protection against Alternaria brassicae, Leptosphaeria maculans and Sclerotinia sclerotiorum. In vitro experiments with proteins extracted from transgenic canola expressing Pm-AMP1 demonstrated its inhibitory activity by reducing growth of fungal hyphae. In addition, the in vitro synthesized peptide also inhibited the growth of the fungi. These results demonstrate that generating transgenic crops expressing PmAMP1 may be an effective and versatile method to protect susceptible crops against multiple phytopathogens.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Brassica napus/microbiologia , Cisteína/metabolismo , Resistência à Doença/efeitos dos fármacos , Fungos/efeitos dos fármacos , Pinus/metabolismo , Doenças das Plantas/microbiologia , Alternaria/efeitos dos fármacos , Alternaria/fisiologia , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/metabolismo , Ascomicetos/efeitos dos fármacos , Ascomicetos/fisiologia , Brassica napus/efeitos dos fármacos , Brassica napus/genética , Sistema Livre de Células , DNA Complementar/genética , Fungos/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta/genética , Immunoblotting , Imuno-Histoquímica , Testes de Sensibilidade Microbiana , Pinus/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Caules de Planta/efeitos dos fármacos , Caules de Planta/microbiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transformação Genética/efeitos dos fármacos
10.
Plant Signal Behav ; 6(11): 1695-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22057337

RESUMO

sn-Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the acylation at sn-1 position of glycerol-3-phosphate to produce lysophosphatidic acid (LPA). LPA is an important intermediate for the formation of different types of acyl-lipids, such as extracellular lipid polyesters, storage and membrane lipids. Three types of GPAT have been found in plants, localizing to the plastid, endoplasmic reticulum, and mitochondria. These GPATs are involved in several lipid biosynthetic pathways and play important biological roles in plant development. In the present review, we will focus on the recent progress in studying the physiological functions of GPATs and their metabolic roles in glycerolipid biosynthesis.


Assuntos
Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Metabolismo dos Lipídeos , Plantas/enzimologia , Retículo Endoplasmático/enzimologia , Ácidos Graxos/biossíntese , Glicerol-3-Fosfato O-Aciltransferase/fisiologia , Glicolipídeos/biossíntese , Mitocôndrias/enzimologia , Plastídeos/enzimologia
11.
FEBS J ; 278(5): 764-75, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21205207

RESUMO

The identification of the yeast phosphatidate phosphohydrolase (PAH1) gene encoding an enzyme with phosphatidate phosphatase (PAP; 3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4) activity led to the discovery of mammalian Lipins and subsequently to homologous genes from plants. In the present study, we describe the functional characterization of Arabidopsis and Brassica napus homologs of PAH1. Recombinant expression studies confirmed that homologous PAHs from plants can rescue different phenotypes exhibited by the yeast pah1Δ strain, such as temperature growth sensitivity and atypical neutral lipid composition. Using this expression system, we examined the role of the putative catalytic motif DXDXT and other conserved residues by mutational analysis. Mutants within the carboxy-terminal lipin domain displayed significantly decreased PAP activity, which was reflected by their limited ability to complement different phenotypes of pah1Δ. Subcellular localization studies using a green fluorescent protein fusion protein showed that Arabidopsis PAH1 is mostly present in the cytoplasm of yeast cells. However, upon oleic acid stimulation, green fluorescent protein fluorescence was predominantly found in the nucleus, suggesting that plant PAH1 might be involved in the transcriptional regulation of gene expression. In addition, we demonstrate that mutation of conserved residues that are essential for the PAP activity of the Arabidopsis PAH1 enzyme did not impair its nuclear localization in response to oleic acid. In conclusion, the present study provides evidence that Arabidopsis and B. napus PAHs restore lipid synthesis in yeast and that DXDXT is a functional enzymic motif within plant PAHs.


Assuntos
Fosfatidato Fosfatase/metabolismo , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Arabidopsis/enzimologia , Brassica napus/enzimologia , Núcleo Celular/metabolismo , Citosol/metabolismo , Microscopia Confocal , Dados de Sequência Molecular , Fosfatidato Fosfatase/genética , Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética
12.
Plant Physiol ; 155(2): 851-65, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21173024

RESUMO

Brassica napus is an allotetraploid (AACC) formed from the fusion of two diploid progenitors, Brassica rapa (AA) and Brassica oleracea (CC). Polyploidy and genome-wide rearrangement during the evolution process have resulted in genes that are present as multiple homologs in the B. napus genome. In this study, three B. napus homologous genes encoding endoplasmic reticulum-bound sn-glycerol-3-phosphate acyltransferase 4 (GPAT4) were identified and characterized. Although the three GPAT4 homologs share a high sequence similarity, they exhibit different expression patterns and altered epigenetic features. Heterologous expression in yeast further revealed that the three BnGPAT4 homologs encoded functional GPAT enzymes but with different levels of polypeptide accumulation. Complementation of the Arabidopsis (Arabidopsis thaliana) gpat4 gpat8 double mutant line with individual BnGPAT4 homologs suggested their physiological roles in cuticle formation. Analysis of gpat4 RNA interference lines of B. napus revealed that the BnGPAT4 deficiency resulted in reduced cutin content and altered stomatal structures in leaves. Our results revealed that the BnGPAT4 homologs have evolved into functionally divergent forms and play important roles in cutin synthesis and stomatal development.


Assuntos
Brassica napus/genética , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Sequência de Bases , Brassica napus/enzimologia , Clonagem Molecular , Retículo Endoplasmático/enzimologia , Epigenômica , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Glicerol-3-Fosfato O-Aciltransferase/genética , Isoenzimas/genética , Isoenzimas/metabolismo , Lipídeos de Membrana/análise , Dados de Sequência Molecular , Mutação , Filogenia , Folhas de Planta/química , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Estômatos de Plantas/fisiologia , Interferência de RNA , RNA de Plantas/genética , Tetraploidia
13.
Plant Cell Rep ; 30(1): 75-80, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21052676

RESUMO

In search for seed coat-specific promoters for canola (Brassica napus), transgenic plants carrying a 2,121 bp fragment of Arabidopsis thaliana At4g12960 promoter (AtGILTpro) fused to the uidA reporter gene (GUS) were generated. Out of 7 independent events in transgenic canola plants raised, 2 exhibited GUS activity exclusively in the outer integument of the seed coat. GUS activity in other tissues was also observed in the remaining five transformants. Therefore, the AtGILT promoter can be used as a canola seed coat outer integument-specific promoter after the generation and selection of desired transformants from several transgenic lines.


Assuntos
Brassica napus/genética , Regiões Promotoras Genéticas , Sementes/genética , Arabidopsis/genética , Brassica napus/citologia , Brassica napus/efeitos dos fármacos , Cinamatos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Glucuronidase/genética , Glucuronidase/metabolismo , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Plantas Geneticamente Modificadas , Polinização/efeitos dos fármacos , Polinização/genética , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Sementes/efeitos dos fármacos , Transformação Genética/efeitos dos fármacos
14.
N Biotechnol ; 27(6): 816-21, 2010 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20933110

RESUMO

Canola is an important agricultural crop imparting a significant contribution to global oilseed production. As such, optimizing yield and quality is of paramount importance and canola production can be significantly affected by sclerotinia stem rot. The utility of recombinant antibody technology in plant protection has been explored by many researchers and shows promise for the generation of new lines of agriculturally significant crops with greater resistance to diseases. The objective of the current study was to generate recombinant pathogen specific antibody (scFv)-expressing transgenic Brassica napus plants with increased tolerance to the phytopathogenic fungus, Sclerotinia sclerotiorum. Transgenic canola (B. napus) lines expressing S. sclerotiorum-specific scFv antibody showed a significant level of tolerance towards S. sclerotiorum as compared to their non-transformed counterparts. Both incidence and progression of S. sclerotiorum-induced disease symptoms were reduced in plants expressing the recombinant scFv.


Assuntos
Ascomicetos/imunologia , Brassica napus , Tolerância Imunológica/imunologia , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas , Anticorpos de Cadeia Única/imunologia , Ascomicetos/patogenicidade , Brassica napus/genética , Brassica napus/imunologia , Brassica napus/microbiologia , Produtos Agrícolas/genética , Produtos Agrícolas/imunologia , Produtos Agrícolas/microbiologia , Doenças das Plantas/imunologia , Folhas de Planta/imunologia , Folhas de Planta/microbiologia , Caules de Planta/imunologia , Caules de Planta/microbiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/microbiologia
15.
Anal Biochem ; 405(1): 138-40, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20522329

RESUMO

Eight reference genes of Brassica napus were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) data, focusing on vegetative tissues and developing embryos. Analyses of expression stability indicated that UP1, UBC9, UBC21, and TIP41 were the top four choices as stably expressed reference genes for vegetative tissues, whereas ACT7, UBC21, TIP41, and PP2A were the top four choices for maturing embryos. In addition, radiolabeling of overall messenger RNA (mRNA) of maturing embryos indicated that the expression patterns of the top four ranked reference genes reflected the overall mRNA content changes in maturing embryos.


Assuntos
Brassica napus/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase/métodos , Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica , Proteínas de Plantas/normas , Reação em Cadeia da Polimerase/normas , RNA Mensageiro/metabolismo , Padrões de Referência
16.
Biotechnol Lett ; 31(12): 1961-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19690805

RESUMO

The canola industry generates more than $11 billion of yearly income to the Canadian economy. One problem of meal quality is the dark polyphenolic pigments that accumulate in the seed coat. Seed coat-specific promoters are a pre-requisite to regulate the genes involved in seed coat development and metabolism. The beta-glucuronidase (GUS) reporter gene was used to test an Arabidopsis promoter in developing and mature seeds of canola (Brassica napus). The promoter tested is the regulatory region of the laccase gene (AtLAC15) from Arabidopsis thaliana. The AtLAC15 promoter::GUS construct was inserted into canola double haploid line DH12075 using Agrobacterium-mediated transformation. Southern blot analysis using a 536 bp GUS probe showed variation among the transformed plants in the T-DNA copy numbers and the position of the insertion in their genomes. Histochemical assay of the GUS enzyme in different tissues (roots, leaves, stem, pollen grains, flowers, siliques, embryos and seed coats) showed ascending GUS activity only in the seed coat from 10 days after pollination (DAP) to the fully mature stage (35 DAP). GUS stain was observed in the mucilage cell layer, in the outer integument layer of the seed coat but not in the inner integument. The AtLAC15 promoter exhibited a specificity and expression level that is useful as a seed coat-specific promoter for canola.


Assuntos
Brassica napus/genética , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Sementes/genética , Arabidopsis/genética , Fusão Gênica Artificial , Brassica napus/química , Brassica napus/fisiologia , Genes Reporter , Vetores Genéticos , Glucuronidase/análise , Glucuronidase/genética , Histocitoquímica , Lacase/genética , Proteínas de Plantas/genética , Rhizobium/genética , Sementes/química
17.
Physiol Plant ; 137(1): 61-71, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19602173

RESUMO

Diacylglycerol acyltransferase (DGAT) catalyzes the acyl-coenzyme A (CoA) dependent acylation of sn-1,2-diacylglycerol to form triacylglycerol in the terminal step of seed oil formation. Previous work has suggested that the level of DGAT activity may have a substantial effect on the flow of carbon into triacylglycerol, implying that the enzyme may represent a promising target for seed oil modification through biotechnological approaches. In the current study, Brassica napus DH12075 was transformed with an antisense type 1 DGAT construct, resulting in a reduction in DGAT1 gene expression, total DGAT activity and seed oil content. In addition, reduced seed yield and germination rates were observed along with severe developmental abnormalities. These data suggest that in addition to its critical role in seed oil formation, DGAT1 enzyme may also be important for normal seed development in B. napus, although the underlying mechanism(s) remain to be determined.


Assuntos
Brassica napus/enzimologia , Brassica napus/crescimento & desenvolvimento , Diacilglicerol O-Aciltransferase/metabolismo , Desenvolvimento Vegetal , RNA Antissenso/metabolismo , Biomassa , Vias Biossintéticas , Ácidos Graxos/metabolismo , Germinação , Microssomos/enzimologia , Óleos de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Transformação Genética , Triglicerídeos/biossíntese
18.
Biotechnol Adv ; 27(6): 866-878, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19625012

RESUMO

The demand for vegetable oils for food, fuel (bio-diesel) and bio-product applications is increasing rapidly. In Canada alone, it is estimated that a 50 to 75% increase in canola oil production will be required to meet the demand for seed oil in the next 7-10years. Plant breeding and genetics have demonstrated that seed oil content is a quantitative trait based on a number of contributing factors including embryo genetic effects, cytoplasmic effects, maternal genetic effects, and genotype-environment interactions. Despite the involvement of numerous quantitative trait loci in determining seed oil content, genetic engineering to over-express/repress specific genes encoding enzymes and other proteins involved in the flow of carbon into seed oil has led to the development of transgenic lines with significant increases in seed oil content. Proteins encoded by these genes include enzymes catalyzing the production of building blocks for oil assembly, enzymes involved in oil assembly, enzymes regulating metabolic carbon partitioning between oil, carbohydrate and secondary metabolite fractions, and transcription factors which orchestrate metabolism at a more general level.


Assuntos
Carbono/química , Óleos de Plantas/química , Sementes/química , DNA Complementar , Fatores de Transcrição/metabolismo , Triglicerídeos/biossíntese
19.
J Exp Bot ; 59(13): 3543-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18703491

RESUMO

Top-down control analysis (TDCA) is a useful tool for quantifying constraints on metabolic pathways that might be overcome by biotechnological approaches. Previous studies on lipid accumulation in oilseed rape have suggested that diacylglycerol acyltransferase (DGAT), which catalyses the final step in seed oil biosynthesis, might be an effective target for enhancing seed oil content. Here, increased seed oil content, increased DGAT activity, and reduced substrate:product ratio are demonstrated, as well as reduced flux control by complex lipid assembly, as determined by TDCA in Brassica napus (canola) lines which overexpress the gene encoding type-1 DGAT. Lines overexpressing DGAT1 also exhibited considerably enhanced seed oil content under drought conditions. These results support the use of TDCA in guiding the rational selection of molecular targets for oilseed modification. The most effective lines had a seed oil increase of 14%. Moreover, overexpression of DGAT1 under drought conditions reduced this environmental penalty on seed oil content.


Assuntos
Brassica napus/genética , Brassica napus/metabolismo , Óleos de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Brassica napus/enzimologia , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/enzimologia
20.
Curr Microbiol ; 57(2): 170-4, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18560939

RESUMO

Four bacterial strains were isolated from soils at nickel-contaminated sites based on their ability to utilize 1-aminocyclopropane-1-carboxylate (ACC) as a sole source of nitrogen. The four isolates were all identified as Pseudomonas putida Biovar B, and subsequent testing revealed that they all exhibited traits previously associated with plant growth promotion (i.e., indoleacetic acid and siderophore production and ACC deaminase activity). These four strains were also tolerant of nickel concentrations of up to 13.2 mM in the culture medium. The strain, HS-2, selected for further characterization, was used in pot experiments to inoculate both nontransformed and transgenic canola plants (expressing a bacterial ACC deaminase gene in its roots). Plants inoculated with the HS-2 strain produced an increase in plant biomass as well as in nickel (Ni) uptake by shoots and roots. The results suggest that this strain is a potential candidate to be used as an inoculant in both phytoremediation protocols and in plant growth promotion.


Assuntos
Antibacterianos/farmacologia , Brassica napus/crescimento & desenvolvimento , Brassica napus/microbiologia , Carbono-Carbono Liases/metabolismo , Níquel/farmacologia , Pseudomonas putida/metabolismo , Antibacterianos/metabolismo , Biomassa , Farmacorresistência Bacteriana , Níquel/metabolismo , Raízes de Plantas/química , Brotos de Planta/química , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/microbiologia , Pseudomonas putida/classificação , Pseudomonas putida/isolamento & purificação , Microbiologia do Solo
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