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1.
aBIOTECH ; 4(4): 277-290, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38106436

RESUMO

Herbicide tolerance has been the dominant trait introduced during the global commercialization of genetically modified (GM) crops. Herbicide-tolerant crops, especially glyphosate-resistant crops, offer great advantages for weed management; however, despite these benefits, glyphosate-resistant maize (Zea mays L.) has not yet been commercially deployed in China. To develop a new bio-breeding resource for glyphosate-resistant maize, we introduced a codon-optimized glyphosate N-acetyltransferase gene, gat, and the enolpyruvyl-shikimate-3-phosphate synthase gene, gr79-epsps, into the maize variety B104. We selected a genetically stable high glyphosate resistance (GR) transgenic event, designated GG2, from the transgenic maize population through screening with high doses of glyphosate. A molecular analysis demonstrated that single copy of gat and gr79-epsps were integrated into the maize genome, and these two genes were stably transcribed and translated. Field trials showed that the transgenic event GG2 could tolerate 9000 g acid equivalent (a.e.) glyphosate per ha with no effect on phenotype or yield. A gas chromatography-mass spectrometry (GC-MS) analysis revealed that, shortly after glyphosate application, the glyphosate (PMG) and aminomethylphosphonic acid (AMPA) residues in GG2 leaves decreased by more than 90% compared to their levels in HGK60 transgenic plants, which only harbored the epsps gene. Additionally, PMG and its metabolic residues (AMPA and N-acetyl-PMG) were not detected in the silage or seeds of GG2, even when far more than the recommended agricultural dose of glyphosate was applied. The co-expression of gat and gr79-epsps, therefore, confers GG2 with high GR and a low risk of herbicide residue accumulation, making this germplasm a valuable GR event in herbicide-tolerant maize breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s42994-023-00114-8.

2.
Plants (Basel) ; 11(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365278

RESUMO

The influence of biotech crops on microbial communities in rhizosphere soil is an important issue in biosafety assessments. The transgenic maize HGK60 harboring the Bt cry1Ah gene enhanced the resistance to lepidopteran pests, while the ecological risk of HGK60 maize on rhizosphere microorganisms is unclear. In this study, we comprehensively analyzed the diversity and composition of bacterial and fungal communities in the rhizosphere soil around Bt maize HGK60 and the near-isogenic non-Bt maize ZD958 at four growth stages via a high-throughput sequencing technique. The results showed that HGK60 maize unleashed temporary effects on the bacterial and fungal diversity and richness during the study plant's development, which would be restored after one cycle of plant cultivation due to the application of the same agricultural management. The differences of bacterial and fungal communities were marked by seasonality, while the different growth stage was the important factor as opposed to the cultivar contributing to the shifts in the bacterial and fungal communities' structure. This study will provide useful information regarding the impact of Bt transgenic maize on the soil microbiome and a theoretical basis for the development of a safety assessment approach for Bt maize in China.

3.
Lancet Psychiatry ; 8(11): 981-990, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34559991

RESUMO

BACKGROUND: In China, depressive disorders have been estimated to be the second leading cause of years lived with disability. However, nationally representative epidemiological data for depressive disorders, in particular use of mental health services by adults with these disorders, are unavailable in China. The present study, part of the China Mental Health Survey, 2012-15, aims to describe the socioeconomic characteristics and the use of mental health services in people with depressive disorders in China. METHODS: The China Mental Health Survey was a cross-sectional epidemiological survey of mental disorders in a multistage clustered-area probability sample of adults of Chinese nationality (≥18 years) from 157 nationwide representative population-based disease surveillance points in 31 provinces across China. Trained investigators interviewed the participants with the Composite International Diagnostic Interview 3.0 to ascertain the presence of lifetime and 12-month depressive disorders according to DSM-IV criteria, including major depressive disorder, dysthymic disorder, and depressive disorder not otherwise specified. Participants with 12-month depressive disorders were asked whether they received any treatment for their emotional problems during the past 12 months and, if so, the specific types of treatment providers. The Sheehan Disability Scale (SDS) was used to assess impairments associated with 12-month depressive symptoms. Data-quality control procedures included logic check by computers, sequential recording check, and phone-call check by the quality controllers, and reinterview check by the psychiatrists. Data were weighted according to the age-sex-residence distribution data from China's 2010 census population survey to adjust for differential probabilities of selection and differential response, as well as to post-stratify the sample to match the population distribution. FINDINGS: 28 140 respondents (12 537 [44·6%] men and 15 603 [55·4%] women) completed the survey between July 22, 2013, and March 5, 2015. Ethnicity data (Han or non-Han) were collected for only a subsample. Prevalence of any depressive disorders was higher in women than men (lifetime prevalence odds ratio [OR] 1·44 [95% CI 1·20-1·72] and 12-month prevalence OR 1·41 [1·12-1·78]), in unemployed people than employed people (lifetime OR 2·38 [95% CI 1·68-3·38] and 12-month OR 2·80 [95% CI 1·88-4·18]), and in people who were separated, widowed, or divorced compared with those who were married or cohabiting (lifetime OR 1·87 [95% CI 1·39-2·51] and 12-month OR 1·85 [95% CI 1·40-2·46]). Overall, 574 (weighted % 75·9%) of 744 people with 12-month depressive disorders had role impairment of any SDS domain: 439 (83·6%) of 534 respondents with major depressive disorder, 207 (79·8%) of 254 respondents with dysthymic disorder, and 122 (59·9%) of 189 respondents with depressive disorder not otherwise specified. Only an estimated 84 (weighted % 9·5%) of 1007 participants with 12-month depressive disorders were treated in any treatment sector: 38 (3·6%) in speciality mental health, 20 (1·5%) in general medical, two (0·3%) in human services, and 21 (2·7%) in complementary and alternative medicine. Only 12 (0·5%) of 1007 participants with depressive disorders were treated adequately. INTERPRETATION: Depressive disorders in China were more prevalent in women than men, unemployed people than employed, and those who were separated, widowed, or divorced than people who were married or cohabiting. Most people with depressive disorders reported social impairment. Treatment rates were very low, and few people received adequate treatment. National programmes are needed to remove barriers to availability, accessibility, and acceptability of care for depression in China. FUNDING: National Health Commission and Ministry of Science and Technology of People's Republic of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Transtorno Distímico/epidemiologia , Serviços de Saúde Mental/estatística & dados numéricos , Vigilância da População/métodos , Adulto , Distribuição por Idade , Idoso , China/epidemiologia , Estudos Transversais , Transtorno Depressivo Maior/tratamento farmacológico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtorno Distímico/tratamento farmacológico , Carga Global da Doença , Humanos , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por Sexo , Fatores Socioeconômicos , Inquéritos e Questionários
4.
Plant Cell ; 31(6): 1328-1343, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30996077

RESUMO

It has long been recognized that stomatal movement modulates CO2 availability and as a consequence the photosynthetic rate of plants, and that this process is feedback-regulated by photoassimilates. However, the genetic components and mechanisms underlying this regulatory loop remain poorly understood, especially in monocot crop species. Here, we report the cloning and functional characterization of a maize (Zea mays) mutant named closed stomata1 (cst1). Map-based cloning of cst1 followed by confirmation with the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR associated protein 9 system identified the causal mutation in a Clade I Sugars Will Eventually be Exported Transporters (SWEET) family gene, which leads to the E81K mutation in the CST1 protein. CST1 encodes a functional glucose transporter expressed in subsidiary cells, and the E81K mutation strongly impairs the oligomerization and glucose transporter activity of CST1. Mutation of CST1 results in reduced stomatal opening, carbon starvation, and early senescence in leaves, suggesting that CST1 functions as a positive regulator of stomatal opening. Moreover, CST1 expression is induced by carbon starvation and suppressed by photoassimilate accumulation. Our study thus defines CST1 as a missing link in the feedback-regulation of stomatal movement and photosynthesis by photoassimilates in maize.


Assuntos
Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Fotossíntese/fisiologia , Proteínas Facilitadoras de Transporte de Glucose/genética , Fotossíntese/genética , Folhas de Planta/metabolismo , Estômatos de Plantas/metabolismo , Zea mays/metabolismo
5.
Sci Rep ; 8(1): 508, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323243

RESUMO

To improve the novel Bacillus thuringiensis insecticidal gene cry2Ah1 toxicity, two mutants cry2Ah1-vp (V354VP) and cry2Ah1-sp (V354SP) were performed. SWISS-MODEL analysis showed two mutants had a longer loop located between ß-4 and ß-5 of domain II, resulting in higher binding affinity with brush border membrane vesicles (BBMV) of Helicoverpa armigera comparing with Cry2Ah1. The cry2Ah1, cry2Ah1-vp, and cry2Ah1-sp were optimized codon usage according to plant codon bias, and named mcry2Ah1, mcry2Ah1-vp, and mcry2Ah1-sp. They were transformed into tobacco via Agrobacterium-mediated transformation and a total of 4, 8, and 24 transgenic tobacco plants were obtained, respectively. The molecular detection showed the exogenous gene was integrated into tobacco genome, and successfully expressed at the transcript and translation levels. Cry2Ah1 protein in transgenic tobacco plants varied from 4.41 to 40.28 µg g-1 fresh weight. Insect bioassays indicated that all transgenic tobacco plants were highly toxic to both susceptible and Cry1Ac-resistant cotton bollworm larvae, and the insect resistance efficiency to Cry1Ac-resistant cotton bollworm was highest in mcry2Ah1-sp transgenic tobacco plants. The results demonstrated that cry2Ah1 was a useful Bt insecticidal gene to susceptible and Cry1Ac-resistant cotton bollworm and had potential application for insect biocontrol and as a candidate for pyramid strategy in Bt crops.


Assuntos
Proteínas de Bactérias/genética , Criptocromos/genética , Resistência a Inseticidas/genética , Mariposas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/farmacologia , Criptocromos/metabolismo , Endotoxinas/farmacologia , Vesículas Extracelulares/metabolismo , Proteínas Hemolisinas/farmacologia , Controle de Insetos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/efeitos dos fármacos , Mutagênese , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Nicotiana/metabolismo
6.
PLoS One ; 12(5): e0177739, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28520800

RESUMO

Chewing insects cause severe yield losses in crop production worldwide. Crop plants counteract chewing insects by transcriptionally promoting a repertoire of defense gene products that are either toxic to, or attractive to the natural enemies of, pest insects. However, the complexity of the transcriptional reprogramming in plant defense response against chewing insects is still not well understood. In this study, the genome-wide early responses in maize seedlings to Asian corn borer (ACB, Ostrinia furnacalis) and also to jasmonic acid(JA), the pivotal phytohormone controlling plant defense response against herbivory, were transcriptionally profiled by RNA-Seq. Clustering of differentially expressed genes (DEGs) along with functional enrichment analysis revealed important biological processes regulated in response to ACB infestation and/or jasmonic acid. Moreover, DEGs with distinct expression patterns were differentially enriched with diverse families of cis-elements on their promoters. Multiple inventories of differentially expressed transcription factors (DETFs) in each DEG group were also analyzed. A transient expression assay using transfected maize protoplastswas established to examine the potential roles of DETFs in maize defense response and JA signaling, and this was used to show that ZmNAC60, an ACB- and JA-inducible DETF, represented a novel positive regulator of JA and defense pathway genes. This study provided a comprehensive transcriptional picture for the early dynamics of maize defense responses and JA signaling, and the identification of DETFs offered potential targets for further functional genomics investigation of master regulators in maize defense responses against herbivory.


Assuntos
Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Mariposas/patogenicidade , Oxilipinas/farmacologia , Transcriptoma , Zea mays/genética , Animais , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/efeitos dos fármacos , Zea mays/parasitologia
7.
Plant J ; 84(2): 296-308, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26303437

RESUMO

Over the past two decades, Zea mays (maize) has been established as a model system for the study of indirect plant defense against herbivores. When attacked by lepidopteran larvae, maize leaves emit a complex blend of volatiles, mainly composed of sesquiterpenes, to attract the natural enemies of the herbivores. This is associated with a swift transcriptional induction of terpene synthases such as TPS10; however, the molecular components controlling the complex transcriptional reprogramming in this process are still obscure. Here, by exploiting the finding that the maize TPS10 promoter retained its full responsiveness to herbivory in Arabidopsis, we identified the region from -300 to -200 of the TPS10 promoter as both necessary and sufficient for its herbivore inducibility through 5' deletion mapping. A high-throughput screening of an Arabidopsis transcription factor library using this promoter region as the bait identified seven AP2/ERF family transcription factors. Among their close homologs in maize, EREB58 was the only gene responsive to herbivory, with a spatiotemporal expression pattern highly similar to that of TPS10. Meanwhile, EREB58 was also responsive to Jasmonate. In vivo and in vitro assays indicated that EREB58 promotes TPS10 expression by directly binding to the GCC-box within the region from -300 to -200 of the TPS10 promoter. Transgenic maize plants overexpressing EREB58 constitutively over-accumulate TPS10 transcript, and also (E)-ß-farnesene and (E)-α-bergamotene, two major sesquiterpenes produced by TPS10. In contrast, jasmonate induction of TPS10 and its volatiles was abolished in EREB58-RNAi transgenic lines. In sum, these results demonstrate that EREB58 is a positive regulator of sesquiterpene production by directly promoting TPS10 expression.


Assuntos
Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Proteínas de Plantas/metabolismo , Sesquiterpenos/metabolismo , Fatores de Transcrição/metabolismo , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/genética , Zea mays/genética
8.
Plant Cell Rep ; 32(8): 1299-308, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23620344

RESUMO

KEY MESSAGE: The study of insect-resistant transgenic tobacco provides a good foundation for the further application of the cry1Ah gene in other important crops. To improve transgene expression levels and insect resistance, the coding sequence of the novel Bacillus thuringiensis insecticidal gene cry1Ah (truncated cry1Ah) was modified according to the codon bias of the plant by increasing its GC content from the original 37 % to 48, 55, and 63 % (designated m1-cry1Ah, m2-cry1Ah, and m3-cry1Ah, respectively). In addition, the m3-cry1Ah gene was linked with a transit peptide sequence for chloroplast-targeted expression (designated ctp-m3-cry1Ah). Four plant expression vectors were constructed harboring m1-cry1Ah, m2-cry1Ah, m3-cry1Ah, or ctp-m3-cry1Ah. A total of 23 transgenic tobacco lines were produced with the four constructs by Agrobacterium tumefaciens-mediated transformation. PCR, Southern hybridization, quantitative RT-PCR and ELISA indicated that the cry1Ah gene was not only integrated into the tobacco genome, but was also successfully expressed at the mRNA and protein levels. The Cry1Ah protein level in ctp-m3-cry1Ah plants reached 4.42 µg/g fresh weight, which was a 2- to 10-fold increase over the levels observed in m1-cry1Ah, m2-cry1Ah, and m3-cry1Ah plants and resulted in the highest resistance to Helicoverpa armigera based on bioassays. Our results demonstrated that combining the codon optimization of cry1Ah gene with the targeting of Cry1Ah protein to the chloroplasts conferred a high level of protection against insects. The results of our experiments in tobacco, an important model system, provide a good foundation for enhancing the insecticidal efficacy of staple crops.


Assuntos
Proteínas de Bactérias/genética , Cloroplastos/metabolismo , Códon/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Lepidópteros/fisiologia , Nicotiana/genética , Nicotiana/parasitologia , Controle Biológico de Vetores , Alelos , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Composição de Bases/genética , Endotoxinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Vetores Genéticos/genética , Proteínas Hemolisinas/metabolismo , Larva/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transformação Genética
9.
Fa Yi Xue Za Zhi ; 24(6): 433-4, 441, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19241970

RESUMO

OBJECTIVE: To investigate changes of brainstem auditory evoked potential (BAEP) in patients with brain concussion. METHODS: Nineteen patients with brain concussion were studied with BAEP examination. The data was compared to the healthy persons reported in literatures. RESULTS: The abnormal rate of BAEP for patients with brain concussion was 89.5%. There was a statistically significant difference between the abnormal rate of patients and that of healthy persons (P<0.05). The abnormal rate of BAEP in the brainstem pathway for patients with brain concussion was 73.7%, indicating dysfunction of the brainstem in those patients. CONCLUSION: BAEP might be helpful in forensic diagnosis of brain concussion.


Assuntos
Concussão Encefálica/diagnóstico , Concussão Encefálica/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Medicina Legal , Acidentes de Trânsito , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Fa Yi Xue Za Zhi ; 23(4): 269-73, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17896517

RESUMO

OBJECTIVE: To analyze epidemiological characteristics of road traffic accidents that resulted in injuries in Chengdu area, to find out the cause and to provide scientific a base for accident prevention. METHODS: Appraisal data of the injured in road traffic accident from January 2003 to October 2006 were re-examined. Detailed statistics were made which include gender, age, transportation mode, person types, the accident date and day, and location. RESULTS: Six thousand three hundred and sixty four cases involving road traffic accident were analyzed. Among the injured, male to female ratio was 1.84:1, and the age group of 18-50 were the largest proportion (66.34%). Bicyclists, motorcyclists and pedestrians made up 80.90% of the injured persons. Different age groups, different genders and those who were injured in different regions varied greatly in terms of transport modes they employed. In terms of injured parts, lower limb injury took up the highest proportion (39.49%), with cranium & cerebrum ranking second (22.77%). CONCLUSION: Different approaches and measures shall be taken in regard to different age groups, different regions, different times and different transport modes, and corresponding policies shall be adopted.


Assuntos
Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Extremidade Inferior/lesões , Masculino , Pessoa de Meia-Idade , Veículos Automotores/estatística & dados numéricos , Traumatismo Múltiplo/epidemiologia , Estudos Retrospectivos , Distribuição por Sexo , Fatores de Tempo , Adulto Jovem
11.
Fa Yi Xue Za Zhi ; 22(1): 61-4, 2006 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-16528833

RESUMO

OBJECTIVE: To discuss the relation between degree of body impairment and that of thoracolumbar spinal injuries resulting from road traffic accidents, and sum up the experiences in body impairment assessment and its regularity. METHODS: For comprehensive body impairment assessment, 477 cases of thoracolumbar spinal injuries in road accidents have been sorted out, reassessed and rediagnosed. In addition, analyses have been undertaken about their treatment, the assessment of the degree of their thoracolumbar dysfunction,nerve dysfunction and the relations between injuries and sequelaes. RESULTS: The analyses show that the degree of thoracolumbar dysfunction and that of the post-injury nerve dysfunction don't necessarily depend on the quantity and degree of spinal injuries. However, the position suffering from the thoracolumbar spinal injuries has an immense impact on the thoracolumbar dysfunction, and the nerve impairment result mainly from the T1-1L spinal injuries. The research also shows that there has been a high misdiagnosis rate in hospital about the spinal injuries. CONCLUSION: In body impairment assessment, the cause and effect relations between the injury and degree of injury extent should be analyzed, the injury extent should be employed as principal evidence, and the degree of spinal dysfunction should be taken into greater consideration.


Assuntos
Acidentes de Trânsito , Avaliação da Deficiência , Vértebras Lombares/lesões , Traumatismos da Coluna Vertebral/diagnóstico , Vértebras Torácicas/lesões , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Escala de Gravidade do Ferimento , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Sistema Nervoso/fisiopatologia , Estudos Retrospectivos , Traumatismos da Coluna Vertebral/fisiopatologia , Vértebras Torácicas/fisiologia , Adulto Jovem
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