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1.
Physiol Plant ; 176(4): e14423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945803

RESUMO

Maize (Zea mays L.) is an important food crop with a wide range of uses in both industry and agriculture. Drought stress during its growth cycle can greatly reduce maize crop yield and quality. However, the molecular mechanisms underlying maize responses to drought stress remain unclear. In this work, a WRKY transcription factor-encoding gene, ZmWRKY30, from drought-treated maize leaves was screened out and characterized. ZmWRKY30 gene expression was induced by dehydration treatments. The ZmWRKY30 protein localized to the nucleus and displayed transactivation activity in yeast. Compared with wild-type (WT) plants, Arabidopsis lines overexpressing ZmWRKY30 exhibited a significantly enhanced drought stress tolerance, as evidenced by the improved survival rate, increased antioxidant enzyme activity by superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), elevated proline content, and reduced lipid peroxidation recorded after drought stress treatment. In contrast, the mutator (Mu)-interrupted ZmWRKY30 homozygous mutant (zmwrky30) was more sensitive to drought stress than its null segregant (NS), characterized by the decreased survival rate, reduced antioxidant enzyme activity (SOD, POD, and CAT) and proline content, as well as increased malondialdehyde accumulation. RNA-Seq analysis further revealed that, under drought conditions, the knockout of the ZmWRKY30 gene in maize affected the expression of genes involved in reactive oxygen species (ROS), proline, and myo-inositol metabolism. Meanwhile, the zmwrky30 mutant exhibited significant downregulation of myo-inositol content in leaves under drought stress. Combined, our results suggest that ZmWRKY30 positively regulates maize responses to water scarcity. This work provides potential target genes for the breeding of drought-tolerant maize.


Assuntos
Resistência à Seca , Inositol , Proteínas de Plantas , Espécies Reativas de Oxigênio , Zea mays , Antioxidantes/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Homeostase , Inositol/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/genética , Zea mays/fisiologia
2.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38203611

RESUMO

Maize is an important food and cash crop worldwide. The WUSCHEL (WUS)-related homeobox (WOX) transcription factor (TF) family plays a significant role in the development process and the response to abiotic stress of plants. However, few studies have been reported on the function of WOX genes in maize. This work, utilizing the latest maize B73 reference genome, results in the identification of 22 putative ZmWOX gene family members. Except for chromosome 5, the 22 ZmWOX genes were homogeneously distributed on the other nine chromosomes and showed three tandem duplication and 10 segmental duplication events. Based on phylogenetic characteristics, ZmWOXs are divided into three clades (e.g., WUS, intermediate, and ancient groups), and the majority of ZmWOXs in same group display similar gene and protein structures. Cross-species collinearity results indicated that some WOX genes might be evolutionarily conservative. The promoter region of ZmWOX family members is enriched in light, plant growth/hormone, and abiotic stress-responsive elements. Tissue-specific expression evaluation showed that ZmWOX genes might play a significant role in the occurrence of maize reproductive organs. Transcriptome data and RT-qPCR analysis further showed that six ZmWOX genes (e.g., ZmWOX1, 4, 6, 13, 16, and 18) were positively or negatively modulated by temperature, salt, and waterlogging stresses. Moreover, two ZmWOXs, ZmWOX1 and ZmWOX18, both were upregulated by abiotic stress. ZmWOX18 was localized in the nucleus and had transactivation activities, while ZmWOX1 was localized in both the cytoplasm and nucleus, without transactivation activity. Overall, this work offers new perspectives on the evolutionary relationships of ZmWOX genes and might provide a resource for further detecting the biological functions of ZmWOXs.


Assuntos
Genes Homeobox , Zea mays , Zea mays/genética , Filogenia , Fatores de Transcrição/genética , Estresse Fisiológico/genética
3.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834181

RESUMO

Maize is often subjected to various environmental stresses. The strictosidine synthase-like (SSL) family is thought to catalyze the key step in the monoterpene alkaloids synthesis pathway in response to environmental stresses. However, the role of ZmSSL genes in maize growth and development and its response to stresses is unknown. Herein, we undertook the systematic identification and analysis of maize SSL genes. Twenty SSL genes were identified in the maize genome. Except for chromosomes 3, 5, 6, and 10, they were unevenly distributed on the remaining 6 chromosomes. A total of 105 SSL genes from maize, sorghum, rice, Aegilops tauschii, and Arabidopsis were divided into five evolutionary groups, and ZmSSL gene structures and conserved protein motifs in the same group were similar. A collinearity analysis showed that tandem duplication plays an important role in the evolution of the SSL family in maize, and ZmSSL genes share more collinear genes in crops (maize, sorghum, rice, and Ae. tauschii) than in Arabidopsis. Cis-element analysis in the ZmSSL gene promoter region revealed that most genes contained many development and stress response elements. We evaluated the expression levels of ZmSSL genes under normal conditions and stress treatments. ZmSSL4-9 were widely expressed in different tissues and were positively or negatively regulated by heat, cold, and infection stress from Colletotrichum graminicola and Cercospora zeina. Moreover, ZmSSL4 and ZmSSL5 were localized in the chloroplast. Taken together, we provide insight into the evolutionary relationships of the ZmSSL genes, which would be useful to further identify the potential functions of ZmSSLs in maize.


Assuntos
Arabidopsis , Zea mays , Zea mays/genética , Zea mays/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regiões Promotoras Genéticas , Motivos de Aminoácidos , Família Multigênica , Filogenia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
4.
J Clin Microbiol ; 48(2): 503-11, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19955277

RESUMO

Although 16S rRNA gene sequence analysis is employed most often for the definitive identification of Nocardia species, alternate molecular methods and polymorphisms in other gene targets have also enabled species determinations. We evaluated a combined Nocardia PCR-based reverse line blot (RLB) hybridization assay based on 16S and 16S-23S rRNA gene spacer region polymorphisms to identify 12 American Type Culture Collection and 123 clinical Nocardia isolates representing 14 species; results were compared with results from 16S rRNA gene sequencing. Thirteen 16S rRNA gene-based (two group-specific and 11 species-specific) and five 16S-23S spacer-targeted (two taxon-specific and three species-specific) probes were utilized. 16S rRNA gene-based probes correctly identified 124 of 135 isolates (sensitivity, 92%) but were unable to identify Nocardia paucivorans strains (n = 10 strains) and a Nocardia asteroides isolate with a novel 16S rRNA gene sequence. Nocardia farcinica and Nocardia cyriacigeorgica strains were identified by the sequential use of an N. farcinica-"negative" probe and a combined N. farcinica/N. cyriacigeorgica probe. The assay specificity was high (99%) except for weak cross-reactivity between the Nocardia brasiliensis probe with the Nocardia thailandica DNA product; however, cross-hybridization with closely related nontarget species may occur. The incorporation of 16S-23S rRNA gene spacer-based probes enabled the identification of all N. paucivorans strains. The overall sensitivity using both probe sets was >99%. Both N. farcinica-specific 16S-23S rRNA gene spacer-directed probes were required to identify all N. farcinica stains by using this probe set. The study demonstrates the utility of a combined PCR/RLB assay for the identification of clinically relevant Nocardia species and its potential for studying subtypes of N. farcinica. Where species assignment is ambiguous or not possible, 16S rRNA gene sequencing is recommended.


Assuntos
Técnicas Bacteriológicas/métodos , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , DNA Ribossômico/genética , Técnicas de Diagnóstico Molecular/métodos , Nocardia/classificação , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos , Humanos , Nocardia/genética , Sondas de Oligonucleotídeos/genética , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade
5.
IEEE Trans Neural Netw ; 19(6): 1075-89, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18541505

RESUMO

In this paper, the recurrent neural networks (RNNs) with a generalized activation function class is proposed. In this proposed model, every component of the neuron's activation function belongs to a convex hull which is bounded by two odd symmetric piecewise linear functions that are convex or concave over the real space. All of the convex hulls are composed of generalized activation function classes. The novel activation function class is not only with a more flexible and more specific description of the activation functions than other function classes but it also generalizes some traditional activation function classes. The absolute exponential stability (AEST) of the RNN with a generalized activation function class is studied through three steps. The first step is to demonstrate the global exponential stability (GES) of the equilibrium point of original RNN with a generalized activation function being equivalent to that of RNN under all vertex functions of convex hull. The second step transforms the RNN under every vertex activation function into neural networks under an array of saturated linear activation functions. Because the GES of the equilibrium point of three systems are equivalent, the next stability analysis focuses on the GES of the equilibrium point of RNN system under an array of saturated linear activation functions. The last step is to study both the existence of equilibrium point and the GES of the RNN under saturated linear activation functions using the theory of M-matrix. In the end, a two-neuron RNN with a generalized activation function is constructed to show the effectiveness of our results.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Dinâmica não Linear , Animais , Simulação por Computador , Modelos Neurológicos , Neurônios/fisiologia , Reconhecimento Automatizado de Padrão/métodos , Fatores de Tempo
6.
Zhongguo Zhong Yao Za Zhi ; 32(9): 831-4, 2007 May.
Artigo em Zh | MEDLINE | ID: mdl-17639987

RESUMO

OBJECTIVE: To investigate the effects of Fufang Banmao capusle on the proteome of SMMC-7721 cells and discover potential molecular mechanism of anti-cancer at molecular level. METHOD: SMMC-7721 cells were treated by Fufang Banmao capusle serum prepared with serum pharmacological method; proteomic protocol involving 2-DE, image analysis and mass spectrometry were used to detect the proteins in cells influenced by Fufang Banmao capusle. RESULT: Approximately 450 protein spots in SMMC-7721 cells were resolved and detected in 2-D gel maps from pH3-10L IEF. 47 protein plots varied over 2-fold quantitively between treated sample and control sample were uncovered. 13 differentially expressed proteins spots were further identified by MALDI-TOF-MS analysis and four of them were successfully identified. Annexin A5, heatshock 70 x 10(3) protein 8 was significantly up-regulated in treated sample compared with control sample, while Eukaryotic translation initiation factor 5A and Peroxiredoxin-2 was significantly down-regulated in treated sample. CONCLUSION: 4 differently expressed proteins associated with the proliferation, apoptosis, immunity of tumor were detected and they might provide clues for the coming research. The protocol of proteomics combined with serum pharmacological method is an effective platform to research complicated formulas in that it is capable of laying out many proteins associated with Fufang Banmao capusle.


Assuntos
Antineoplásicos/farmacologia , Materia Medica/farmacologia , Proteoma/efeitos dos fármacos , Proteômica/métodos , Animais , Anexina A5/metabolismo , Antineoplásicos/isolamento & purificação , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Besouros/química , Combinação de Medicamentos , Eletroforese em Gel Bidimensional , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Materia Medica/isolamento & purificação , Fatores de Iniciação de Peptídeos/metabolismo , Peroxirredoxinas/metabolismo , Proteoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Coelhos , Soro , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fator de Iniciação de Tradução Eucariótico 5A
7.
Exp Ther Med ; 13(3): 971-975, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28450928

RESUMO

The effect of etomidate on the oxidative stress response and levels of inflammatory factors resulting from ischemia-reperfusion injury of the lower extremities during tibial fracture surgery were investigated. From December 2013 to June 2015, 60 tibial fracture patients with surgical indications for open reduction and internal fixation were selected. Patients were randomly divided into the observation group and the control group. All patients were stanched by tourniquet hemostasis. Patients in the observation group were anesthetized with etomidate (3-6 mg/kg·h) + remifentanil (0.1-0.25 µg/kg/min) administered with an injection pump to maintain intraoperative sedation and analgesia anesthesia. Patients in the control group received propofol (3-6 mg/kg·h) + remifentanil (0.1-0.25 µg/kg/min). Before surgery (T0), before surgery was completed and anesthesia was stopped (T1), 24 h after surgery (T3), 48 h after surgery (T4), and 1 week after surgery (T5), serum superoxide dismutase (SOD) activity was determined with a kit, and ELISA was used to measure the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1, and IL-6 in peripheral blood from both groups of patients. Surgery in both groups was completed smoothly. We found that serum SOD levels of patients in the observation group were significantly higher than those of the control group, while the levels of TNF-α, IL-1, and IL-6 released by neutrophils were significantly decreased after ischemia-reperfusion injury (P<0.05). Postoperative length of stay in hospital of the observation group was significantly shorter and the occurrence rate of anesthesia complications was significantly lower than in the control group (P<0.05). In conclusion, during surgery for lower limb fracture, the use of etomidate for maintaining sedation can effectively maintain serum SOD activity and inhibit the release of inflammatory factors after ischemia-reperfusion injury of the fracture, to reduce the occurrence rate of anesthesia complications after surgery.

8.
Artigo em Inglês | MEDLINE | ID: mdl-18238166

RESUMO

In this paper, we consider the H/sub 2/ sampled-data control for uncertain linear systems by the impulse response interpretation of the H/sub 2/ norm. Two H/sub 2/ measures for sampled-data systems are considered. The robust optimal control procedures subject to these two H/sub 2/ criteria are proposed. The development is primarily concerned with a multirate treatment in which a periodic time-varying robust optimal control for uncertain linear systems is presented. To facilitate multirate control design, a new result of stability of hybrid system is established. Moreover, the single-rate case is also obtained as a special case. The sampling period is explicitly involved in the result which is superior to traditional methods. The solution procedures proposed in this paper are formulated as an optimization problem subject to linear matrix inequalities. Finally, we present a numerical example to demonstrate the proposed techniques.

9.
Pathology ; 43(5): 488-94, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21670723

RESUMO

OBJECTIVES: Human adenoviruses are common pathogens associated with a broad spectrum of disease. There is a growing clinical interest in typing clinical isolates since it is becoming increasingly clear that individual serotypes are associated with different disease spectra, virulence, severity of consequences, and outbreaks. Current methods cannot detect all known adenoviruses simultaneously and rapidly. We designed a practical adenovirus typing method with polymerase chain reaction (PCR)-based reverse line blot hybridisation assay (RLB) using hypervariable region-7 (HVR-7) in the hexon gene. METHODS: A PCR-RLB assay was developed based on HVR-7 in the hexon region for potentially genotyping 51 adenovirus serotypes by hybridisation of 62 genotype-specific probes using amplicons generated from one genus-specific primer pair. Single PCR and sequencing were performed for confirmation of RLB results. Eighty-seven previously serotyped clinical isolates (representing 28 serotypes) were studied. RESULTS: Thirty-two different genotypes were detected by RLB from 87 adenovirus isolates, of which 82 isolates showed consistent results with sequencing. Another five isolates revealed evidence by RLB of co-infection, and were confirmed with a combination of genotype-specific single PCR and sequencing. CONCLUSIONS: In comparison to sequencing and serological methods, the advantages of the RLB assay include: (1) rapid genotyping of multiple samples in a single run; (2) successful detection of co-infection; (3) detection of subgenotype variants. This will allow rapid and inexpensive characterisation of adenovirus infections and outbreaks.


Assuntos
Adenoviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adenoviridae/classificação , Adenoviridae/genética , Sequência de Bases , DNA Viral/análise , Genótipo , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sorotipagem
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