Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Plant Physiol Biochem ; 149: 144-152, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32066082

RESUMO

Anthocyanins contribute greatly to the organoleptic and biochemical properties of grapes and wines. Although there are broadly documented factors involved in grape anthocyanin synthesis, the present work focused on fungal endophytes and their possible role in grape coloration. Our results showed that exposure to endophytic fungi within a dual culture system differentially affected total anthocyanin concentrations and PAL activities in grape cells. Grape cells dual cultured with fungal strains XH-2, R2-21 and B2-17 showed significant differences of their anthocyanin concentrations were subjected to further analysis of their anthocyanidin compositions. Compared to the no-fungus controls, grape cells exposed to fungal strains XH-2 and R2-21 exhibited quantitative promotion of their total anthocyanidin concentrations by 74% and 28%, respectively, whereas treatment with the fungus B2-17 reduced the anthocyanidin content by 19%. A total of 14 species of anthocyanidins were detected from the grape cells in these experiments. Most interestingly, exposure to any of these fungal strains differentially modified the compositional patterns of grape cellular anthocyanidins. The obvious upregulation of the transcription of VvMYB in grape cells treated with fungal strains XH-2 and R2-21 implies that the increased anthocyanin levels in these grape cells may be due to the activated transcriptional factors. In addition, the exposure of grape cells to extracts of these fungi initiated similar responses of anthocyanin contents and PAL activities to exposure to the living fungi and appeared obvious dosage effects. The influence of fungal endophytes on the coloration of grape berries was also examined in this study.

2.
BMC Microbiol ; 19(1): 158, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291888

RESUMO

BACKGROUND: Gastrodia elata is a widely distributed achlorophyllous orchid and is highly valued as both medicine and food. Gastrodia elata produces dust-like seeds and relies on mycorrhizal fungi for its germination and growth. In its life cycle, G. elata is considered to switch from a specific single-fungus relationship (Mycena) to another single-fungus relationship (Armillaria). However, no studies have investigated the changes in the plant-fungus relationship during the growth of G. elata in the wild. In this study, high-throughput sequencing was used to characterize the fungal community of tubers in different growth phases as well as the soils surrounding G. elata. RESULTS: The predominant fungi were Basidiomycota (60.44%) and Ascomycota (26.40%), which exhibited changes in abundance and diversity with the growth phases of G. elata. Diverse basidiomycetes in protocorms (phase P) were Hyphodontia, Sistotrema, Tricholoma, Mingxiaea, Russula, and Mycena, but the community changed from a large proportion of Resinicium bicolor (40%) in rice-like tubers (phase M) to an unidentified Agaricales operational taxonomic unit 1(OTU1,98.45%) in propagation vegetation tubers (phase B). The soil fungi primarily included Simocybe, Psathyrella, Conocybe, and Subulicystidium. Three Mycena OTUs obtained in this study were differentially distributed among the growth phases of G. elata, accounting for less than 1.0% of the total reads, and were phylogenetically close to Mycena epipterygia and M. alexandri. CONCLUSIONS: Our data indicated that G. elata interacts with a broad range of fungi beyond the Mycena genus. These fungi changed with the growth phases of G. elata. In addition, these data suggested that the development of the fungal community during the growth of G. elata was more complex than previously assumed and that at least two different fungi could be involved in development before the arrival of Armillaria.

3.
PLoS One ; 13(5): e0196996, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734364

RESUMO

Since endophytes can affect metabolism of host plants, they are expected to be used to improve crop quality, especially for crops with organoleptic sensitive products such as wine grape. However, details of metabolic interactions between endophytes and host plants were less understood. In this work, we used high pressure liquid chromatography (HPLC) to analyze the metabolites of fruit flesh cells of grape treated with dual culture of different endophytic fungal strains (EFS). We observed that the dual-culture with different fungal strains show different metabolites composition in grape cells. In response to different EFS, quantities of detected metabolites in grape cells varied from 6 to 17 in this assay, and 1 to 11 novel metabolites were introduced into metabolome of grape cells. Dual-culture with fungal strains CS2, RH16 and RH5 introduced the highest quantities (10 or 11) of novel metabolites in grape cells. More importantly, the modification of metabolic profiles in grape cells via fungal endophytes appeared to be fungal strain/genus-specificity. Overall, this work revealed that introduction of specific metabolites in host plants may be one consequence during the process of endophytes-host metabolic interactions, which raise the possibility to shape grape qualities and characteristics using tool of fungal endophytes.


Assuntos
Endófitos/metabolismo , Fungos/metabolismo , Metaboloma/genética , Vitis/metabolismo , Cromatografia Líquida de Alta Pressão , Endófitos/patogenicidade , Frutas/metabolismo , Frutas/microbiologia , Fungos/patogenicidade , Filogenia , Vitis/microbiologia
4.
PLoS One ; 11(9): e0163186, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656886

RESUMO

Endophytes proved to exert multiple effects on host plants, including growth promotion, stress resistance. However, whether endophytes have a role in metabolites shaping of grape has not been fully understood. Eight endophytic fungal strains which originally isolated from grapevines were re-inoculated to field-grown grapevines in this study, and their effects on both leaves and berries of grapevines at maturity stage were assessed, with special focused on secondary metabolites and antioxidant activities. High-density inoculation of all these endophytic fungal strains modified the physio-chemical status of grapevine to different degrees. Fungal inoculations promoted the content of reducing sugar (RS), total flavonoids (TF), total phenols (TPh), trans-resveratrol (Res) and activities of phenylalanine ammonia-lyase (PAL), in both leaves and berries of grapevine. Inoculation of endophytic fungal strains, CXB-11 (Nigrospora sp.) and CXC-13 (Fusarium sp.) conferred greater promotion effects in grape metabolic re-shaping, compared to other used fungal strains. Additionally, inoculation of different strains of fungal endophytes led to establish different metabolites patterns of wine grape. The work implies the possibility of using endophytic fungi as fine-tuning regulator to shape the quality and character of wine grape.

5.
Sensors (Basel) ; 15(1): 1623-34, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25594598

RESUMO

The design and fabrication of an ethanol microsensor integrated with a readout circuit on-a-chip using the complementary metal oxide semiconductor (CMOS)-microelectro -mechanical system (MEMS) technique are investigated. The ethanol sensor is made up of a heater, a sensitive film and interdigitated electrodes. The sensitive film is tin dioxide that is prepared by the sol-gel method. The heater is located under the interdigitated electrodes, and the sensitive film is coated on the interdigitated electrodes. The sensitive film needs a working temperature of 220 °C. The heater is employed to provide the working temperature of sensitive film. The sensor generates a change in capacitance when the sensitive film senses ethanol gas. A readout circuit is used to convert the capacitance variation of the sensor into the output frequency. Experiments show that the sensitivity of the ethanol sensor is 0.9 MHz/ppm.

6.
Sensors (Basel) ; 14(11): 20360-71, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25353984

RESUMO

The study develops an integrated humidity microsensor fabricated using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The integrated humidity sensor consists of a humidity sensor and a ring oscillator circuit on-a-chip. The humidity sensor is composed of a sensitive film and branch interdigitated electrodes. The sensitive film is zinc oxide prepared by sol-gel method. After completion of the CMOS process, the sensor requires a post-process to remove the sacrificial oxide layer and to coat the zinc oxide film on the interdigitated electrodes. The capacitance of the sensor changes when the sensitive film adsorbs water vapor. The circuit is used to convert the capacitance of the humidity sensor into the oscillation frequency output. Experimental results show that the output frequency of the sensor changes from 84.3 to 73.4 MHz at 30 °C as the humidity increases 40 to 90%RH.


Assuntos
Condutometria/instrumentação , Eletrodos , Umidade , Oscilometria/instrumentação , Semicondutores , Transdutores , Água/análise , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização , Transição de Fase , Integração de Sistemas
7.
Sensors (Basel) ; 14(7): 12735-47, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25036331

RESUMO

This study investigates the fabrication and characterization of an acetone microsensor with a ring oscillator circuit using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The acetone microsensor contains a sensitive material, interdigitated electrodes and a polysilicon heater. The sensitive material is α-Fe2O3 synthesized by the hydrothermal method. The sensor requires a post-process to remove the sacrificial oxide layer between the interdigitated electrodes and to coat the α-Fe2O3 on the electrodes. When the sensitive material adsorbs acetone vapor, the sensor produces a change in capacitance. The ring oscillator circuit converts the capacitance of the sensor into the oscillation frequency output. The experimental results show that the output frequency of the acetone sensor changes from 128 to 100 MHz as the acetone concentration increases 1 to 70 ppm.


Assuntos
Acetona/química , Desenho de Equipamento/instrumentação , Óxidos/química , Semicondutores , Capacitância Elétrica , Eletrodos , Compostos Férricos/química , Gases/química
8.
Sensors (Basel) ; 13(11): 14728-39, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24172287

RESUMO

This study investigates the design and fabrication of magnetic microsensors using the commercial 0.35 µm complementary metal oxide semiconductor (CMOS) process. The magnetic sensor is composed of springs and interdigitated electrodes, and it is actuated by the Lorentz force. The finite element method (FEM) software CoventorWare is adopted to simulate the displacement and capacitance of the magnetic sensor. A post-CMOS process is utilized to release the suspended structure. The post-process uses an anisotropic dry etching to etch the silicon dioxide layer and an isotropic dry etching to remove the silicon substrate. When a magnetic field is applied to the magnetic sensor, it generates a change in capacitance. A sensing circuit is employed to convert the capacitance variation of the sensor into the output voltage. The experimental results show that the output voltage of the magnetic microsensor varies from 0.05 to 1.94 V in the magnetic field range of 5-200 mT.

9.
Sensors (Basel) ; 13(10): 12760-70, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24072022

RESUMO

The study investigates the fabrication and characterization of an ethanol microsensor equipped with a heater. The ethanol sensor is manufactured using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The sensor consists of a sensitive film, a heater and interdigitated electrodes. The sensitive film is zinc oxide prepared by the sol-gel method, and it is coated on the interdigitated electrodes. The heater is located under the interdigitated electrodes, and it is used to supply a working temperature to the sensitive film. The sensor needs a post-processing step to remove the sacrificial oxide layer, and to coat zinc oxide on the interdigitated electrodes. When the sensitive film senses ethanol gas, the resistance of the sensor generates a change. An inverting amplifier circuit is utilized to convert the resistance variation of the sensor into the output voltage. Experiments show that the sensitivity of the ethanol sensor is 0.35 mV/ppm.


Assuntos
Condutometria/instrumentação , Eletrodos , Etanol/análise , Calefação/instrumentação , Semicondutores , Impedância Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Etanol/química , Miniaturização , Transdutores
10.
Sensors (Basel) ; 13(3): 3664-74, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23503294

RESUMO

The study presents an ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 µm complementary metal oxide semiconductor (CMOS) process. The integrated sensor chip consists of a heater, an ammonia sensor and a readout circuit. The ammonia sensor is constructed by a sensitive film and the interdigitated electrodes. The sensitive film is zirconium dioxide that is coated on the interdigitated electrodes. The heater is used to provide a working temperature to the sensitive film. A post-process is employed to remove the sacrificial layer and to coat zirconium dioxide on the sensor. When the sensitive film adsorbs or desorbs ammonia gas, the sensor produces a change in resistance. The readout circuit converts the resistance variation of the sensor into the output voltage. The experiments show that the integrated ammonia sensor has a sensitivity of 4.1 mV/ppm.


Assuntos
Amônia/química , Dispositivos Lab-On-A-Chip , Semicondutores , Zircônio/química , Eletrodos , Gases/química , Temperatura Ambiente
11.
Sensors (Basel) ; 13(2): 2359-67, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23396193

RESUMO

This paper presents the fabrication and characterization of energy harvesting thermoelectric micro generators using the commercial complementary metal oxide semiconductor (CMOS) process. The micro generator consists of 33 thermocouples in series. Thermocouple materials are p-type and n-type polysilicon since they have a large Seebeck coefficient difference. The output power of the micro generator depends on the temperature difference in the hot and cold parts of the thermocouples. In order to increase this temperature difference, the hot part of the thermocouples is suspended to reduce heat-sinking. The micro generator needs a post-CMOS process to release the suspended structures of hot part, which the post-process includes an anisotropic dry etching to etch the sacrificial oxide layer and an isotropic dry etching to remove the silicon substrate. Experiments show that the output power of the micro generator is 9.4 mW at a temperature difference of 15 K.

12.
Sensors (Basel) ; 11(10): 9798-806, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163726

RESUMO

A high Q-factor (quality-factor) spiral inductor fabricated by the CMOS (complementary metal oxide semiconductor) process and a post-process was investigated. The spiral inductor is manufactured on a silicon substrate. A post-process is used to remove the underlying silicon substrate in order to reduce the substrate loss and to enhance the Q-factor of the inductor. The post-process adopts RIE (reactive ion etching) to etch the sacrificial oxide layer, and then TMAH (tetramethylammonium hydroxide) is employed to remove the silicon substrate for obtaining the suspended spiral inductor. The advantage of this post-processing method is its compatibility with the CMOS process. The performance of the spiral inductor is measured by an Agilent 8510C network analyzer and a Cascade probe station. Experimental results show that the Q-factor and inductance of the spiral inductor are 15 at 15 GHz and 1.8 nH at 1 GHz, respectively.


Assuntos
Eletrônica/instrumentação , Eletrônica/normas , Metais/química , Sistemas Microeletromecânicos/instrumentação , Sistemas Microeletromecânicos/métodos , Óxidos/química , Semicondutores , Desenho de Equipamento , Interferometria , Microscopia Eletrônica de Varredura , Controle de Qualidade
13.
Sensors (Basel) ; 11(8): 8143-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22164067

RESUMO

This study presents the fabrication and characterization of a humidity microsensor that consists of interdigitated electrodes and a sensitive film. The area of the humidity microsensor is about 2 mm(2). The sensitive film is polyaniline doping polyvinyl alcohol (PVA) that is prepared by the sol-gel method, and the film has nanofiber and porous structures that help increase the sensing reaction. The commercial 0.35 µm Complimentary Metal Oxide Semiconductor (CMOS) process is used to fabricate the humidity microsensor. The sensor needs a post-CMOS process to etch the sacrificial layer and to coat the sensitive film on the interdigitated electrodes. The sensor produces a change in resistance as the polyaniline/PVA film absorbs or desorbs vapor. Experimental results show that the sensitivity of the humidity sensor is about 12.6 kΩ/%RH at 25 °C.


Assuntos
Compostos de Anilina/química , Sistemas Microeletromecânicos/métodos , Polímeros/química , Álcool de Polivinil/química , Monitoramento Ambiental/métodos , Desenho de Equipamento , Umidade , Metais/química , Sistemas Microeletromecânicos/instrumentação , Microscopia Eletrônica de Varredura/métodos , Óxidos/química , Semicondutores , Espectrofotometria/métodos , Temperatura Ambiente
14.
Sensors (Basel) ; 11(12): 11112-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22247656

RESUMO

A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 µm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature.


Assuntos
Amônia/análise , Nanotubos , Semicondutores , Óxido de Zinco/química , Eletrodos
15.
J Microbiol ; 48(2): 139-45, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20437143

RESUMO

Invasive plants have caused great economic losses and environmental problems worldwide. Eupatorium adenophorum is one of the most invasive weeds in China. To better understand its invasive mechanisms, in the present paper, the microbial communities of healthy and diseased leaves of E. adenophorum were obtained using both culture-independent and -dependent methods and their diversities were compared. The bacteria obtained from culture-independent method belong to Proteobacteria (95.8%), Actinobacteria (2.1%), and Firmicutes (2.1%) and fungi belong to Ascomycota (65.2%) and Basidiomycota (34.8%). Very few overlapped microbial species were found by culture-dependent and -independent methods. Healthy leaves display higher bacterial diversity than diseased leaves. Phylogenetic structures are very different between healthy and diseased phyllosphere microbial communities. Bacteria close to Acinetobacter and Pseudomonas were dominant on healthy leaves, whereas those close to Shigella were dominant on diseased leaves. 52.9% of fungal clones from healthy leaves were Ustilaginomycetes, close to Rhodotorula phylloplana and uncultured basidomycete; by contrast, 60% of clones from diseased leaves were Lecanoromycetes, close to Umbilicaria muehlenbergii. No bacteria but four fungal strains phylogenetically close to Myrothecium sp. and Alternaria alternate were pathogenic to seedlings and detached leaves of the invasive plant. Therefore, this plant may be resistant to pathogens from bacteria but not fungi in its introduced range.


Assuntos
Ageratina/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Fungos/classificação , Fungos/isolamento & purificação , Doenças das Plantas/microbiologia , Bactérias/genética , Bactérias/crescimento & desenvolvimento , China , Análise por Conglomerados , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/genética , Fungos/crescimento & desenvolvimento , Metagenômica , Dados de Sequência Molecular , Filogenia , Folhas de Planta/microbiologia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
16.
Sensors (Basel) ; 10(11): 10095-104, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22163459

RESUMO

This study presents the design and fabrication of a capacitive micro humidity sensor integrated with a five-stage ring oscillator circuit on chip using the complimentary metal oxide semiconductor (CMOS) process. The area of the humidity sensor chip is about 1 mm(2). The humidity sensor consists of a sensing capacitor and a sensing film. The sensing capacitor is constructed from spiral interdigital electrodes that can enhance the sensitivity of the sensor. The sensing film of the sensor is polypyrrole, which is prepared by the chemical polymerization method, and the film has a porous structure. The sensor needs a post-CMOS process to coat the sensing film. The post-CMOS process uses a wet etching to etch the sacrificial layers, and then the polypyrrole is coated on the sensing capacitor. The sensor generates a change in capacitance when the sensing film absorbs or desorbs vapor. The ring oscillator circuit converts the capacitance variation of the sensor into the oscillation frequency output. Experimental results show that the sensitivity of the humidity sensor is about 99 kHz/%RH at 25 °C.


Assuntos
Umidade , Sistemas Microeletromecânicos/métodos , Polímeros/química , Pirróis/química , Desenho de Equipamento , Sistemas Microeletromecânicos/instrumentação
17.
World J Gastroenterol ; 15(15): 1892-6, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19370789

RESUMO

AIM: To evaluate hepatic recurrence and prognostic factors for survival in patients with surgically resected hilar cholangiocarcinoma in a single institution over the last 13 years. METHODS: From 1994 to 2007, all patients with hilar cholangiocarcinoma referred to a surgical clinic were evaluated. Demographic data, tumor characteristics, and outcome were analyzed retrospectively. Outcome was compared in patients who underwent additional liver resection with resection of the tumor. RESULTS: Of the 69 patients submitted to laparotomy for tumor resection, curative resection (R(0) resection) was performed in 40 patients, and palliative resection in 29. Thirty-one patients had only duct resection, and 38 patients had combined duct resection with liver resection including 34 total or part caudate lobes. Curative rates with the combined hepatectomy were significantly improved compared with those without additional hepatectomy (27/38 vs 13/31; chi2 = 5.94, P < 0.05). Concomitant liver resection was associated with a decreased incidence of initial recurrence in liver one year after surgery (11/38 vs 23/31; chi2 = 13.98, P < 0.01). The 3-year survival rate after R(0) resection was 30.7% and was 10.5% for palliative resection. R(0) resection improved the 3-year survival rate (30.7% vs 10.5%; chi2 = 12.47, P < 0.01). CONCLUSION: Hepatectomy, especially including the caudate lobe combined with bile duct resection should be considered standard treatment to cure hilar cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/cirurgia , Neoplasias Hepáticas/patologia , Idoso , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Hepatectomia , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
18.
Yi Chuan ; 30(6): 776-80, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18550503

RESUMO

The cDNA library of Yuanjiang Oryza rifupongon leaf was constructed by using SMART technology. The titers of the non-amplified library and the amplified library were 1.1 x 106 pfu/mL and 3.98 x 107 pfu/mL, respectively. The recombination rate was more than 91%. The DNA sequence length of the most cDNAs in the library was between 500-2 000 bp. Some cDNAs chosen by random were sequenced. After BLAST analysis of some cDNAs, their possible function were predicted. It is found that these cDNAs show 98% similarity to Oryza sativa japonica in the NCBI database. These provided a base for further study on the structure and function of these cDNAs and evolutionary process of Yuanjiang Oryza rifupongon.


Assuntos
Biblioteca Gênica , Oryza/genética , Folhas de Planta/genética , China , Bases de Dados Genéticas , Reação em Cadeia da Polimerase
19.
Yi Chuan ; 30(1): 109-14, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18244911

RESUMO

A 4,672 bp DNA sequence including the whole coding region and partial non-coding region of rice blast resistance gene Pi-ta+ has been cloned from Jinghong erect type of common wild rice (Oryza rufipogon Griff) in Yunnan by polymerase chain reaction method. The coding region shares 99.86% and 98.78% identity with the corresponding regions of the reported cultivated rice Yashiro-mochi and Yuanjiang type of common wild rice respectively. There are 4 nucleotides difference in the coding region and 6 in intron of the cloned Pi-ta+ gene,compared with Pi-ta from Yashiro-mochi. Pi-ta+ gene in Jinghong erect type of common wild rice has been proved to be a rare existing Pi-ta+ allele, because there was a alanine rather than a serine at the position 918 within the predicted amino acid sequence of PITA. Pi-ta+ allele can cause disease resistance response to rice blast pathogens in plant cells. Differences in DNA sequence, deduced amino acid sequence and antibacterial spectrum may make the Pi-ta+ allele new resistant characteristics. Finding and cloning of Pi-ta+ allele from Jinghong erect type of common wild rice in Yunnan provides a basement for further utilization of the wild rice resources.


Assuntos
Alelos , Genes de Plantas/genética , Oryza/genética , Oryza/fisiologia , Doenças das Plantas , Sequência de Aminoácidos , China , Clonagem Molecular , DNA Complementar/genética , Íntrons/genética , Técnicas de Amplificação de Ácido Nucleico , Polimorfismo Genético , Análise de Sequência de DNA , Regiões não Traduzidas/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-18349514

RESUMO

Compared to Pi-ta(-) alleles, Pi-ta(+) alleles can cause blast resistance response. In this work, Pi-ta gene in multiple rice materials, including local rice cultivars, different types of O. rufipogon and O. longistaminata was detected by molecular cloning and sequence analysis. Results indicated that Pi-ta(+) alleles were rare alleles, because in all the tested materials, only the 'Erect' type of O. rufipogon (ETOR) from Jinghong county in Yunnan province contains a Pi-ta(+) allele. Another rice blast resistance gene, Pib, confers resistance to the Japanese strain of M. grisea, was also confirmed to be functional in this type of O. rufipogon. The results of pathogen inoculation test show that ETOR is more strongly resistant to the tested blast pathogen races than other types of O. rufipogon. The resistance of ETOR may at least partially depend upon the functioning of Pi-ta and Pib gene. As O. rufipogon has the same type of genome with the cultivated rice (O. sativa), Pi-ta(+) and Pib gene in Erect type of O. rufipogon can be used to improve the tolerance of cultivated rice to blast, either by traditional hybridization or by genetic engineering.


Assuntos
Imunidade Inata/genética , Magnaporthe/fisiologia , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA