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1.
J Infect Public Health ; 17(6): 956-960, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608456

RESUMO

BACKGROUND: After the eradication of smallpox, there have been no specific public health measures for any Orthopoxviruses (OPXVs). Therefore, it is necessary to countermeasure OPXV infections after Mpox (formerly monkeypox) occurrences, such as the latest global outbreak in 2022-2023. This study aimed to provide crucial insights for the development of effective public health policy making against mpox in populations residing in regions where the virus is not prevalent. METHODS: This study used enzyme-linked immunosorbent assays (ELISA) to examine smallpox and mpox antibodies in Koreans with three different age groups. We analyzed 56 sera obtained from a tertiary care hospital in South Korea between September 2022 and April 2023. Plasma levels of antibodies against the viral proteins of smallpox (variola cytokine response-modifying protein B) and MPXV (A29) were measured using enzyme-linked immunosorbent assays. RESULTS: Plasma samples from participants in their early 40 s and older exhibited higher reactivity to viral antigens than those from younger participants. Furthermore, there was a strong positive correlation in antibody positivity for the two different viruses across the sera. CONCLUSIONS: The presence of low antibody levels in participants ˂40 years may hinder their ability to defend against OPXV. Therefore, it is imperative to implement effective public health measures to mitigate the transmission of OPXV within the community. These findings serve as fundamental information for devising strategies to combat mpox efficiently, particularly in regions where the virus is not prevalent.


Assuntos
Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Orthopoxvirus , Humanos , Adulto , Anticorpos Antivirais/sangue , República da Coreia/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Feminino , Orthopoxvirus/imunologia , Fatores Etários , Saúde Pública , Idoso , Adolescente , Formação de Anticorpos , Varíola/prevenção & controle , Varíola/imunologia , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/epidemiologia , Mpox/epidemiologia , Mpox/imunologia
2.
Commun Biol ; 6(1): 879, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640792

RESUMO

Characterizing the host response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the molecular level is necessary to understand viral pathogenesis and identify clinically relevant biomarkers. However, in humans, the pulmonary host response during disease onset remains poorly understood. Herein, we utilized a spatial transcriptome atlas to identify pulmonary microstructure-specific COVID-19 gene signatures during the acute phase of lung infection in cynomolgus macaques. The innate immune response to virus-induced cell death was primarily active in the alveolar regions involving activated macrophage infiltration. Inflamed vascular regions exhibited prominent upregulation of interferon and complement pathway genes that mediate antiviral activity and tissue damage response. Furthermore, known biomarker genes were significantly expressed in specific microstructures, and some of them were universally expressed across all microstructures. These findings underscore the importance of identifying key drivers of disease progression and clinically applicable biomarkers by focusing on pulmonary microstructures appearing during SARS-CoV-2 infection.


Assuntos
Ascomicetos , COVID-19 , Humanos , Animais , COVID-19/genética , SARS-CoV-2 , Transcriptoma , Macaca fascicularis , Pulmão
3.
J Med Virol ; 95(6): e28847, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37272485

RESUMO

Recently emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variants are generally less pathogenic than previous strains. However, elucidating the molecular basis for pulmonary immune response alterations is challenging owing to the virus's heterogeneous distribution within complex tissue structure. Here, we revealed the spatial transcriptomic profiles of pulmonary microstructures at the SARS-CoV-2 infection site in the nine cynomolgus macaques upon inoculation with the Delta and Omicron variants. Delta- and Omicron-infected lungs had upregulation of genes involved in inflammation, cytokine response, complement, cell damage, proliferation, and differentiation pathways. Depending on the tissue microstructures (alveoli, bronchioles, and blood vessels), there were differences in the types of significantly upregulated genes in each pathway. Notably, a limited number of genes involved in cytokine and cell damage response were differentially expressed between bronchioles of the Delta- and Omicron-infection groups. These results indicated that despite a significant antigenic shift in SARS-CoV-2, the host immune response mechanisms induced by the variants were relatively consistent, with limited transcriptional alterations observed only in large airways. This study may aid in understanding the pathogenesis of SARS-CoV-2 and developing a clinical strategy for addressing immune dysregulation by identifying potential transcriptional biomarkers within pulmonary microstructures during infection with emerging variants.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , SARS-CoV-2/genética , Transcriptoma , COVID-19/genética , Alvéolos Pulmonares , Citocinas/genética , Macaca
4.
Cancers (Basel) ; 13(21)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34771705

RESUMO

Previous studies have suggested that statins can be repurposed for cancer treatment. However, the therapeutic efficacy of statins in chronic myeloid leukemia (CML) has not yet been demonstrated. In this study, we retrospectively evaluated the outcomes of 408 CML patients who underwent imatinib therapy. The deep molecular response rates in patients treated with the statin/TKI combination were significantly higher than those in patients treated with TKI alone (p = 0.0016). The statin/TKI combination exerted potent cytotoxic effects against wild-type and ABL1 mutant CML, BaF3, and K562/T315I mutant cells. Furthermore, the statin/TKI combination additively inhibited the colony-forming capacity of murine CML-KLS+ cells in vitro. In addition, we examined the additive growth-inhibitory effects of the statin/tyrosine kinase inhibitor (TKI) combination against CML patient-derived CD34+ cells. The growth-inhibitory effects of the statin/imatinib combination against CD34+/CML primary cells were higher than those against CD34+/Norm cells (p = 0.005), suggesting that the combination of rosuvastatin and imatinib exerted growth-inhibitory effects against CML CD34+ cells, but not against normal CD34+ cells. Furthermore, results from RNA sequencing of control and statin-treated cells suggested that statins inhibited c-Myc-mediated and hematopoietic cell differentiation pathways. Thus, statins can be potentially repurposed to improve treatment outcomes in CML patients when combined with TKI therapy.

5.
ChemSusChem ; 11(1): 120-124, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29105332

RESUMO

Lithium-mediated reduction of dinitrogen is a promising method to evade electron-stealing hydrogen evolution, a critical challenge which limits faradaic efficiency (FE) and thus hinders the success of traditional protic-solvent-based ammonia electro-synthesis. A viable implementation of the lithium-mediated pathway using lithium-ion conducting glass ceramics involves i) lithium deposition, ii) nitridation, and iii) ammonia formation. Ammonia was successfully synthesized from molecular nitrogen and water, yielding a maximum FE of 52.3 %. With an ammonia synthesis rate comparable to previously reported approaches, the fairly high FE demonstrates the possibility of using this nitrogen fixation strategy as a substitute for firmly established, yet exceedingly complicated and expensive technology, and in so doing represents a next-generation energy storage system.


Assuntos
Amônia/síntese química , Cerâmica/química , Técnicas Eletroquímicas/métodos , Vidro/química , Lítio/química , Nitrogênio/química , Água/química
6.
J Agric Food Chem ; 61(43): 10354-9, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24070395

RESUMO

The transgenic rice cultivar of Oryza sativa spp. japonica cv. Hwa-Young, C1/R-S transgenic rice (C1/R-S rice), is a flavonoid-rich cultivar of rice. The grains of C1/R-S rice were extracted with aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH, and H2O, successively. Repeated silica gel, octadecyl silica gel (ODS), and Sephadex LH-20 column chromatographies for the EtOAc and n-BuOH fractions afforded four new flavonoids (compounds 2, 3, 7, and 8) along with four known flavonoids: (+)-3'-O-methyltaxifolin (1), brassicin (4), isorhamnetin-4'-O-ß-D-glucosyranoside (5), and 3'-O-methyltaxifolin-5-O-ß-D-glucopyranoside (6). The new flavonoids were identified as 3'-O-methyltaxifolin-7-O-ß-D-glucopyranoside (2), 3'-O-methyltaxifolin-4'-O-ß-D-glucopyranoside (3), isorhamnetin-7-O-ß-D-cellobioside (brassicin-4″-O-ß-D-glucopyranoside) (7), and brassicin-4'-O-ß-D-glucosyranoside (8) from the result of spectroscopic data including nuclear magnetic resonance spectrometry (NMR), mass spectrometry (MS), and infrared spectroscopy (IR). Also, quantitative analysis of major flavonoids (compounds 2, 3, and 8) in C1/R-S rice, O. sativa spp. japonica cv. Hwa-Young (HY), and a hybrid of two cultivar (C1/R-S rice/HY) extracts was performed using HPLC experiment. The isolated flavonoids were evaluated for their radical-scavenging effect on DPPH and ABTS radicals.


Assuntos
Flavonoides/análise , Sequestradores de Radicais Livres/análise , Oryza/química , Extratos Vegetais/análise , Plantas Geneticamente Modificadas/química , Cromatografia Líquida de Alta Pressão , Flavonoides/metabolismo , Sequestradores de Radicais Livres/metabolismo , Oryza/genética , Oryza/metabolismo , Extratos Vegetais/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
7.
Planta ; 235(2): 387-97, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21927949

RESUMO

In eukaryotes, the cell cycle consists of four distinct phases: G1, S, G2 and M. In certain condition, the cells skip M-phase and undergo endoreduplication. Endoreduplication, occurring during a modified cell cycle, duplicates the entire genome without being followed by M-phase. A cycle of endoreduplication is common in most of the differentiated cells of plant vegetative tissues and it occurs extensively in cereal endosperm cells. Endoreduplication occurs when CDK/Cyclin complex low or inactive caused by ubiquitin-mediated degradation by APC and their activators. In this study, rice cell cycle switch 52 A (OsCCS52A), an APC activator, is functionally characterized using the reverse genetic approach. In rice, OsCCS52A is highly expressed in seedlings, flowers, immature panicles and 15 DAP kernels. Localization studies revealed that OsCCS52A is a nuclear protein. OsCCS52A interacts with OsCdc16 in yeast. In addition, overexpression of OsCCS52A inhibits mitotic cell division and induces endoreduplication and cell elongation in fission yeast. The homozygous mutant exhibits dwarfism and smaller seeds. Further analysis demonstrated that endoreduplication cycles in the endosperm of mutant seeds were disturbed, evidenced by reduced nuclear and cell sizes. Taken together, these results suggest that OsCCS52A is involved in maintaining normal seed size formation by mediating the exit from mitotic cell division to enter the endoreduplication cycles in rice endosperm.


Assuntos
Endosperma/genética , Oryza/genética , Proteínas de Plantas/metabolismo , RNA de Plantas/genética , Sequência de Aminoácidos , Ciclossomo-Complexo Promotor de Anáfase , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Crescimento Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Tamanho Celular , Clonagem Molecular , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Endosperma/crescimento & desenvolvimento , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mitose , Dados de Sequência Molecular , Mutação , Fases de Leitura Aberta , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Componentes Aéreos da Planta/genética , Componentes Aéreos da Planta/crescimento & desenvolvimento , Componentes Aéreos da Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Polinização , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Transformação Genética , Técnicas do Sistema de Duplo-Híbrido , Complexos Ubiquitina-Proteína Ligase/genética , Complexos Ubiquitina-Proteína Ligase/metabolismo
8.
New Phytol ; 185(1): 103-13, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19765229

RESUMO

We identified and functionally characterized the AtSKIP gene (At1g77180), an Arabidopsis homologue of SNW/SKIP, under abiotic stresses. Although the SNW/SKIP protein has been implicated as a critical transcription cofactor, its biological functions have yet to be reported in any plant. Recently, we have isolated Salt-tolerance genes (SATs) via the overexpression screening of yeast with a maize cDNA library. One of the selected genes (SAT2) appeared to confer elevated tolerance to salt. Maize SAT2 cDNA encodes a homologue of the human SNW/SKIP transcriptional coregulator. Treatment with salt, mannitol and abscisic acid induced AtSKIP expression. Ectopic expression of the AtSKIP gene modulated the induction of salt tolerance, dehydration resistance and insensitivity towards abscisic acid under stress conditions. By contrast, atskip antisense lines displayed reduced tolerance to abiotic stresses during germination. Moreover, a decrease in AtSKIP expression resulted in an abnormal phenotype. We further determined that the AtSKIP protein activated the transcription of a reporter gene in yeast. Green fluorescent protein-tagged AtSKIP was localized in the nuclei of both onion cells and transgenic Arabidopsis cells. Taken together, these results suggest that AtSKIP functions as both a positive regulator and putative potential transcription factor in the abiotic stress signalling pathway.


Assuntos
Ácido Abscísico/genética , Adaptação Fisiológica/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo , Ácido Abscísico/fisiologia , Acetiltransferases/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , DNA Complementar , Desidratação , Biblioteca Gênica , Genes de Plantas , Genes Reporter , Germinação , Humanos , Manitol , Mutação , Cebolas , Osmose , Fenótipo , Plantas Geneticamente Modificadas , Tolerância ao Sal/genética , Cloreto de Sódio , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Leveduras/genética , Zea mays/genética
9.
Plant Cell Rep ; 28(3): 397-406, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19050897

RESUMO

Purple-colored transgenic creeping bentgrass (Agrostis stolonifera L.) plants were developed for ornamental purpose by means of Agrobacterium-mediated transformation. Embryogenic creeping bentgrass calli were transformed with the pCAMBIA 3301 vector harboring maize (Zea mays) flavonoid/anthocyanin biosynthetic pathway transcription factor genes, Lc (Leaf color) and Pl (Purple leaf), individually and in combination, and three types of putative transgenic plants (Lc, Pl, and Lc + Pl) were generated. Genomic integration and expression of the transgenes were confirmed by Southern and northern blot analyses, respectively. The transgenic creeping bentgrass plants expressing both Lc and Pl genes were entirely purple, whereas those expressing Pl alone had purple stems and those expressing Lc alone lacked purple pigmentation in adult plants. The anthocyanin content was estimated in all the three types of transgenic plant and correlated well with the degree of purple coloration observed. These results suggest that both Lc and Pl genes are necessary and sufficient to confer purple coloration to creeping bentgrass.


Assuntos
Agrostis/genética , Pigmentação/genética , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética , Zea mays/genética , Antocianinas/biossíntese , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Técnicas de Transferência de Genes , Genes de Plantas , Fenótipo , Proteínas de Plantas/genética , Rhizobium/genética , Transformação Genética
10.
Plant J ; 55(3): 455-66, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18410480

RESUMO

Despite the fact that glycine-rich RNA-binding proteins (GRPs) have been implicated in the responses of plants to environmental stresses, their physiological functions and mechanisms of action in stress responses remain largely unknown. Here, we assessed the functional roles of GRP7, one of the eight GRP family members in Arabidopsis thaliana, on seed germination, seedling growth, and stress tolerance under high salinity, drought, or cold stress conditions. The transgenic Arabidopsis plants overexpressing GRP7 under the control of the cauliflower mosaic virus 35S promoter displayed retarded germination and poorer seedling growth compared with the wild-type plants and T-DNA insertional mutant lines under high salinity or dehydration stress conditions. By contrast, GRP7 overexpression conferred freezing tolerance in Arabidopsis plants. GRP7 is expressed abundantly in the guard cells, and has been shown to influence the opening and closing of the stomata, in accordance with the prevailing stress conditions. GRP7 is localized to both the nucleus and the cytoplasm, and is involved in the export of mRNAs from the nucleus to the cytoplasm under cold stress conditions. Collectively, these results provide compelling evidence that GRP7 affects the growth and stress tolerance of Arabidopsis plants under high salt and dehydration stress conditions, and also confers freezing tolerance, particularly via the regulation of stomatal opening and closing in the guard cells.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Estômatos de Plantas/fisiologia , Proteínas de Ligação a RNA/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/análise , Proteínas de Arabidopsis/genética , Núcleo Celular/química , Núcleo Celular/metabolismo , Citoplasma/química , Citoplasma/metabolismo , Congelamento , Germinação/genética , Mutagênese Insercional , Plantas Geneticamente Modificadas/fisiologia , Poli A/metabolismo , Transporte de RNA/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/análise , Proteínas de Ligação a RNA/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Cloreto de Sódio/metabolismo , Água/metabolismo
11.
Plant Physiol ; 147(1): 156-68, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18354041

RESUMO

Plant MADS-box genes can be divided into 11 groups. Genetic analysis has revealed that most of them function in flowering-time control, reproductive organ development, and vegetative growth. Here, we elucidated the role of OsMADS26, a member of the AGL12 group. Transcript levels of OsMADS26 were increased in an age-dependent manner in the shoots and roots. Transgenic plants of both rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana) overexpressing this gene manifested phenotypes related to stress responses, such as chlorosis, cell death, pigment accumulation, and defective root/shoot growth. In addition, apical hook development was significantly suppressed in Arabidopsis. Plants transformed with the OsMADS26-GR (glucocorticoid receptor) fusion construct displayed those stress-related phenotypes when treated with dexamethasone. Microarray analyses using this inducible system showed that biosynthesis genes for jasmonate, ethylene, and reactive oxygen species, as well as putative downstream targets involved in the stress-related process, were up-regulated in OsMADS26-overexpressing plants. These results suggest that OsMADS26 induces multiple responses that are related to various stresses.


Assuntos
Proteínas de Domínio MADS/genética , Oryza/genética , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Expressão Gênica , Genes de Plantas , Oryza/fisiologia , Fenótipo , Proteínas Recombinantes de Fusão/metabolismo , Regulação para Cima
12.
Plant Foods Hum Nutr ; 63(2): 53-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18213519

RESUMO

Serotonin N-hydroxycinnamoyltransferase (SHT) is a key enzyme in the synthesis of feruloylserotonin (FS) and 4-coumaroylserotonin (CS). These serotonin derivatives show strong antioxidant activity, making them valuable for both nutritional and pharmacological use in humans. Ectopic expression of SHT under the control of the endosperm specific-glutelin and prolamin promoters from rice was produced via Agrobacterium-mediated transformation. SHT expression was confirmed by Southern blot analysis, followed by Northern blotting and SHT enzyme activity analyses using total RNA and protein, respectively, extracted from transgenic seeds. The glutelin A3 (GluA3) promoter produced low SHT mRNA expression in rice seeds, whereas the prolamin promoter expressed high levels of SHT mRNA. In spite of the ectopic expression of SHT in rice seeds, both transgenic genotypes accumulated levels of serotonin derivatives similar to those found in wild-type rice. Furthermore, our data suggest that serotonin, rather than phenylpropanid-CoAs, is the rate-limiting substrate in the biosynthesis of serotonin derivatives in SHT-overexpressing transgenic rice seeds.


Assuntos
Arilalquilamina N-Acetiltransferase/metabolismo , Oryza/enzimologia , Oryza/genética , Serotonina/análogos & derivados , Serotonina/biossíntese , Ácidos Cumáricos/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Serotonina/metabolismo , Tiramina/análogos & derivados , Tiramina/metabolismo
13.
Plant Physiol Biochem ; 45(9): 722-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17761429

RESUMO

We conducted a genetic yeast screen to identify Thermo-tolerance genes (TTOs) in maize kernel cDNA library. During the screening, we identified a maize clone (TTO6) that seemed to confer elevated heat tolerance in comparison to control cells. TTO6 cDNA (GenBank accession no. AY103785) encodes an 11-kDa protein which is 69% similarity to the Arabidopsis GASA4 gene. To further examine heat tolerance in Arabidopsis, we functionally characterized the GASA4 gene and found that heat induced GASA4 expression. Constitutive expression of GASA4 in Arabidopsis led to elevated heat tolerance in transgenic lines. Interestingly, endoplasmic reticulum chaperone expression analysis suggests that GASA4 influences BiP gene expression during heat stress.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Zea mays/genética , Zea mays/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , DNA Bacteriano/genética , DNA de Plantas/genética , Dados de Sequência Molecular , Plantas Geneticamente Modificadas
14.
Plant Mol Biol ; 65(1-2): 125-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17619151

RESUMO

Increasing its root to shoot ratio is a plant strategy for restoring water homeostasis in response to the long-term imposition of mild water stress. In addition to its important role in diverse fundamental processes, indole-3-acetic acid (IAA) is involved in root growth and development. Recent extensive characterizations of the YUCCA gene family in Arabidopsis and rice have elucidated that member's function in a tryptophan-dependent IAA biosynthetic pathway. Through forward- and reverse-genetics screening, we have isolated Tos17 and T-DNA insertional rice mutants in a CONSTITUTIVELY WILTED1 (COW1) gene, which encodes a new member of the YUCCA protein family. Homozygous plants with either a Tos17 or T-DNA-inserted allele of OsCOW1 exhibit phenotypes of rolled leaves, reduced leaf widths, and lower root to shoot ratios. These phenotypes are evident in seedlings as early as 7-10 d after germination, and remain until maturity. When oscow1 seedlings are grown under low-intensity light and high relative humidity, the rolled-leaf phenotype is greatly alleviated. For comparison, in such conditions, the transpiration rate for WT leaves decreases approx. 5- to 10-fold, implying that this mutant trait results from wilting rather than being a morphogenic defect. Furthermore, a lower turgor potential and transpiration rate in their mature leaves indicates that oscow1 plants are water-deficient, due to insufficient water uptake that possibly stems from that diminished root to shoot ratio. Thus, our observations suggest that OsCOW1-mediated IAA biosynthesis plays an important role in maintaining root to shoot ratios and, in turn, affects water homeostasis in rice.


Assuntos
Homeostase , Família Multigênica/genética , Oryza/enzimologia , Oxigenases/metabolismo , Raízes de Plantas/enzimologia , Brotos de Planta/enzimologia , Água/metabolismo , Sequência de Aminoácidos , DNA Bacteriano/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Ácidos Indolacéticos/metabolismo , Dados de Sequência Molecular , Mutação/genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Oxigenases/química , Oxigenases/classificação , Oxigenases/genética , Fenótipo , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Triptaminas/biossíntese
15.
Plant Biotechnol J ; 4(3): 303-15, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-17147636

RESUMO

Flavonoids, compounds that possess diverse health-promoting benefits, are lacking in the endosperm of rice. Therefore, to develop transgenic lines that produce flavonoids, we transformed a white rice cultivar, Oryza sativa japonica cv. Hwa-Young, with maize C1 and R-S regulatory genes. Expression of these transgenes was restricted to the endosperm using the promoter of a rice prolamin gene. The pericarp of the C1/R-S homozygous lines became dark brown in accordance with their maternal genotype, whereas the endosperm turned chalky, similar to the opaque kernel phenotype. Analysis via high-performance liquid chromatography (HPLC) revealed that numerous kinds of flavonoids were produced in these transgenic kernels. To identify individual flavonoids, the number of HPLC peaks was reduced through moderate acid hydrolysis, followed by ethyl acetate partitioning. Amongst the major flavonoids, dihydroquercetin (taxifolin), dihydroisorhamnetin (3'-O-methyl taxifolin) and 3'-O-methyl quercetin were identified through liquid chromatography/mass spectrometry/mass spectrometry and nuclear magnetic resonance analyses. Fluorescence labelling with diphenylboric acid showed that the flavonoids were highly concentrated in the cells of four to five outer endosperm layers. More importantly, a high fluorescence signal was present in the cytosol of the inner endosperm layers. However, the overall signal in the inner layers was significantly lower because starch granules and protein bodies occupied most of the cytosolic space. Our estimate of the total flavonoid content in the transgenic kernels suggests that C1/R-S rice has the potential to be developed further as a novel variety that can produce various flavonoids in its endosperm.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Flavonoides/biossíntese , Oryza/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Sementes/metabolismo , Fatores de Transcrição/metabolismo , Zea mays/genética , Cromatografia Líquida de Alta Pressão , Proteínas de Ligação a DNA/genética , Flavonoides/química , Oryza/anatomia & histologia , Oryza/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/anatomia & histologia , Fatores de Transcrição/genética , Transformação Genética , Transgenes
16.
J Altern Complement Med ; 12(8): 813-5, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17034288

RESUMO

OBJECTIVES: The aim of this study was to ascertain the effects of contralateral acupuncture on brain function using blind-spot mapping. DESIGN AND PARTICIPANTS: Forty (40) healthy volunteers in whom the right-side blind spot was larger than the left-side one-which indicates lower left-brain function-were randomly assigned into the following two groups in which electroacupuncture was applied to: (1) the contralateral ST36 acupuncture point (right side), and (2) the ipsilateral ST36 acupuncture point (left side). OUTCOME MEASURE: Blind-spot perimetry length was the outcome measure. RESULTS: Electroacupuncture to the contralateral side decreased the blind-spot perimetry length by 5.0 (-9.3 to 0.9) [median (interquartile range, IQR)], whereas that to the ipsilateral side increased the length by 4.5 (-3.7 to 7.8) [median, IQR]. There was significant difference in this length between the two groups (p < 0.05). CONCLUSIONS: These results suggest that electroacupuncture application increased or decreased the brain function- as assessed by changes to the blind spot-depending on the treatment side: Contralateral-side treatment has a better effect than ipsilateral-side treatment on brain function. However, further randomized studies that include both right- and left-side-enlarged subjects with a sham needle are needed to convincingly show the effects of contralateral acupuncture on brain function.


Assuntos
Mapeamento Encefálico/métodos , Eletroacupuntura/métodos , Disco Óptico/fisiologia , Pontos de Acupuntura , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valores de Referência
17.
Plant Cell ; 16(7): 1854-69, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15208390

RESUMO

Cells in maize (Zea mays) endosperm undergo multiple cycles of endoreduplication, with some attaining DNA contents as high as 96C and 192C. Genome amplification begins around 10 d after pollination, coincident with cell enlargement and the onset of starch and storage protein accumulation. Although the role of endoreduplication is unclear, it is thought to provide a mechanism that increases cell size and enhances gene expression. To investigate this process, we reduced endoreduplication in transgenic maize endosperm by ectopically expressing a gene encoding a dominant negative mutant form of cyclin-dependent kinase A. This gene was regulated by the 27-kD gamma-zein promoter, which restricted synthesis of the defective enzyme to the endoreduplication rather than the mitotic phase of endosperm development. Overexpression of a wild-type cyclin-dependent kinase A increased enzyme activity but had no effect on endoreduplication. By contrast, ectopic expression of the defective enzyme lowered kinase activity and reduced by half the mean C-value and total DNA content of endosperm nuclei. The lower level of endoreduplication did not affect cell size and only slightly reduced starch and storage protein accumulation. There was little difference in the level of endosperm gene expression with high and low levels of endoreduplication, suggesting that this process may not enhance transcription of genes associated with starch and storage protein synthesis.


Assuntos
Quinases Ciclina-Dependentes/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mutação , Zea mays/genética , Ciclo Celular , Núcleo Celular/metabolismo , Tamanho Celular , Citometria de Fluxo , Histonas/metabolismo , Fosforilação , Plantas Geneticamente Modificadas , Sementes/citologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Zea mays/citologia , Zeína/genética
18.
Proc Natl Acad Sci U S A ; 99(18): 11975-80, 2002 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-12185243

RESUMO

The genome of the Mastreviruses encodes a replication-associated protein (RepA) that interacts with members of the plant retinoblastoma-related protein family, which are putative cell cycle regulators. Expression of ZmRb1, a maize retinoblastoma-related gene, and RepA inhibited and stimulated, respectively, cell division in tobacco cell cultures. The effect of RepA was mitigated by over-expression of ZmRb1. RepA increased transformation frequency and callus growth rate of high type II maize germplasm. RepA-containing transgenic maize calli remained embryogenic, were readily regenerable, and produced fertile plants that transmitted transgene expression in a Mendelian fashion. In high type II, transformation frequency increased with the strength of the promoter driving RepA expression. When a construct in which RepA was expressed behind its native LIR promoter was used, primary transformation frequencies did not improve for two elite Pioneer maize inbreds. However, when LIR:RepA-containing transgenic embryos were used in subsequent rounds of transformation, frequencies were higher in the RepA+ embryos. These data demonstrate that RepA can stimulate cell division and callus growth in culture, and improve maize transformation.


Assuntos
Ciclo Celular , DNA Helicases , Proteínas de Ligação a DNA , Proteína do Retinoblastoma/metabolismo , Transativadores , Zea mays/citologia , Divisão Celular , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Proteínas/fisiologia , Zea mays/metabolismo
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