RESUMO
The anti-malarial drug, artemisinin, is quite expensive as a result of its slow content in Artemisia annua. Recent investigations have suggested that genetic engineering of A. annua is a promising approach to improve the yield of artemisinin. In this study, the transgenic A. annua strain GYR, which has high artemisinin content, was evaluated in an environmental release trial. First, GYR plants were compared with the wild-type variety NON-GYR, with regard to phenotypic characters (plant height, crown width, stem diameter, germination rate, leaf dry weight, 1000-seed weight, leave shape). Second, stress resistance in the two varieties (salt, drought, herbicide, and cold resistance) was evaluated under different experimental conditions. Finally, gene flow was estimated. The results indicated that there were significant differences in several agronomic traits (plant height, stem diameter, and leave dry weight) between the transgenic GYR and NON-GYR plants. Salt stress in transgenic and control plants was similar, except under high NaCl concentrations (1.6%, w/w). Leaf water, proline, and MDA content (increased significantly) were significantly different. Transgenic A. annua GYR plants did not grow better than NON-GYR plants with respect to drought and herbicide resistance. The two varieties maintained vitality through the winter. Third, gene flow was studied in an environmental risk trial for transgenic GYR. The maximum gene flow frequency was 2.5%, while the maximum gene flow distance was 24.4 m; gene flow was not detected at 29.2 m at any direction. Our findings may provide an opportunity for risk assessment in future commercialization of transgenic A. annua varieties.
Assuntos
Antimaláricos/metabolismo , Artemisia annua/genética , Artemisininas/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Adaptação Fisiológica/genética , Antimaláricos/isolamento & purificação , Artemisia annua/metabolismo , Artemisininas/isolamento & purificação , Temperatura Baixa , Secas , Fluxo Gênico , Engenharia Genética , Germinação/genética , Temperatura Alta , Malondialdeído/metabolismo , Fenótipo , Folhas de Planta/metabolismo , Prolina/metabolismo , Salinidade , Estresse FisiológicoRESUMO
The demand for molecular analysis of aquatic microbial communities in freshwater has highlighted the need for efficient methods of DNA extraction. The centrifugation method and filtration-membrane method are 2 widely used methods for extracting DNA. The objective of this study was to compare the extraction efficiency of 3 methods, including the centrifugation method, filtration-membrane method, and modified filtration-membrane method, by evaluating the quantity and purity of DNA extracts obtained from water. DNA extraction was analyzed by agarose gel electrophoresis, ultraviolet-spectroscopy, restriction enzyme digestion, and polymerase chain reaction. The results showed that the modified filtration-membrane method was the most efficient for extracting microbial DNA from freshwater with high integrity and purity and is suitable for molecular applications.
Assuntos
Bactérias/isolamento & purificação , Centrifugação/métodos , Cromatografia em Gel/métodos , DNA Bacteriano/isolamento & purificação , Bactérias/genética , DNA Bacteriano/genética , Água Doce/microbiologiaRESUMO
OBJECTIVE: Glioblastomas are one of the most dangerous types of malignancies because of their metastatic capacity and challenge to treat with chemotherapy or radiotherapy. Hence, detailed research to explain the molecular mechanisms of glioblastoma metastasis is crucial to improve glioblastoma treatment. PATIENTS AND METHODS: The expression level of fatty acid-binding protein 4 (FABP4) in glioblastoma cell lines and tissues was detected by Western blotting and quantitative Real-time polymerase chain reaction (qRT-PCR) assays. Proliferation assay, colon formation analysis and transwell/migration assay were performed to detect the relationship between FABP4 and malignant behaviors of glioblastoma cells in vitro. Subcutaneous xenograft and intravenous metastasis models were used to determine the role of FABP4 in vitro. Rescue assays were conducted to confirm the contribution of Wingless-Type MMTV Integration Site Family, Member 10B (Wnt10b) to the progression of glioblastoma cells regulated by FABP4. RESULTS: Glioblastoma cells exhibited a higher level of FABP4 expression than control cells, and down-regulation of FABP4 suppressed tumor cell growth and metastasis in vitro and in vivo. Wnt10b, as a regulator gene of FABP4, restored the effects of FABP4 down-regulation in glioblastoma cells. CONCLUSIONS: We provided substantive evidence that FABP4 is a growth and metastasis promoter in vivo and revealed that it functions in part through Wnt10b, which suggests that FABP4 might act as a probable target to block glioblastoma metastasis.