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Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used for human non-small-cell lung cancer (NSCLC) treatment. However, acquired resistance to EGFR-TKIs is the major barrier of treatment success, and new resistance mechanism remains to be elucidated. In this study, we found that elevated NADPH oxidase 4 (NOX4) expression was associated with acquired EGFR-TKIs resistance. Gefitinib is the first-generation FDA-approved EGFR-TKI, and osimertinib is the third-generation FDA-approved EGFR-TKI. We demonstrated that NOX4 knockdown in the EGFR-TKI resistant cells enabled the cells to become sensitive to gefitinib and osimertinib treatment, while forced expression of NOX4 in the sensitive parental cells was sufficient to induce resistance to gefitinib and osimertinib in the cells. To elucidate the mechanism of NOX4 upregulation in increasing TKIs resistance, we found that knockdown of NOX4 significantly down-regulated the expression of transcription factor YY1. YY1 bound directly to the promoter region of IL-8 to transcriptionally activate IL-8 expression. Interestingly, knockdown of NOX4 and IL-8 decreased programmed death ligand 1 (PD-L1) expression, which provide new insight on TKIs resistance and immune escape. We found that patients with higher NOX4 and IL-8 expression levels showed a shorter survival time compared to those with lower NOX4 and IL-8 expression levels in response to the anti-PD-L1 therapy. Knockdown of NOX4, YY1 or IL-8 alone inhibited angiogenesis and tumor growth. Furthermore, the combination of NOX4 inhibitor GKT137831 and gefitinib had synergistic effect to inhibit cell proliferation and tumor growth and to increase cellular apoptosis. These findings demonstrated that NOX4 and YY1 were essential for mediating the acquired EGFR-TKIs resistance. IL-8 and PD-L1 are two downstream targets of NOX4 to regulate TKIs resistance and immunotherapy. These molecules may be used as potential new biomarkers and therapeutic targets for overcoming TKIs resistance in the future.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinogênese , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Interleucina-8/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , NADPH Oxidase 4/genética , /farmacologiaRESUMO
BACKGROUND: Betalain is a natural pigment with important nutritional value and broad application prospects. Previously, we produced betanin biosynthesis transgenic carrots via expressing optimized genes CYP76AD1S, cDOPA5GTS and DODA1S. Betanin can accumulate throughout the whole transgenic carrots. But the effects of betanin accumulation on the metabolism of transgenic plants and whether it produces unexpected effects are still unclear. RESULTS: The accumulation of betanin in leaves can significantly improve its antioxidant capacity and induce a decrease of chlorophyll content. Transcriptome and metabolomics analysis showed that 14.0% of genes and 33.1% of metabolites were significantly different, and metabolic pathways related to photosynthesis and tyrosine metabolism were markedly altered. Combined analysis showed that phenylpropane biosynthesis pathway significantly enriched the differentially expressed genes and significantly altered metabolites. CONCLUSIONS: Results showed that the metabolic status was significantly altered between transgenic and non-transgenic carrots, especially the photosynthesis and tyrosine metabolism. The extra consumption of tyrosine and accumulation of betanin might be the leading causes.
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Daucus carota , Daucus carota/genética , Betacianinas , Fotossíntese/genética , TirosinaRESUMO
Currently, feed enzymes are primarily obtained through fermentation of fungi, bacteria, and other microorganisms. Although the manufacturing technology for feed enzymes has evolved rapidly, the activities of these enzymes decline during the granulating process and the cost of application has increased over time. An alternative approach is the use of genetically modified plants containing complex feed enzymes for direct utilization in animal feedstuff. We co-expressed three commonly used feed enzymes (phytase, ß-glucanase, and xylanase) in barley seeds using the Agrobacterium-mediated transformation method and generated a new barley germplasm. The results showed that these enzymes were stable and had no effect on the development of the seeds. Supplementation of the basal diet of laying hens with only 8% of enzyme-containing seeds decreased the quantities of indigestible carbohydrates, improved the availability of phosphorus, and reduced the impact of animal production on the environment to an extent similar to directly adding exogenous enzymes to the feed. Feeding enzyme-containing seeds to layers significantly increased the strength of the eggshell and the weight of the eggs by 10.0%-11.3% and 5.6%-7.7% respectively. The intestinal microbiota obtained from layers fed with enzyme-containing seeds was altered compared to controls and was dominated by Alispes and Rikenella. Therefore, the transgenic barley seeds produced in this study can be used as an ideal feedstuff for use in animal feed.
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6-Fitase , Hordeum , Animais , Feminino , Galinhas , Dieta , Sementes , Engenharia Genética , Ração Animal/análise , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição AnimalRESUMO
2,4-Dinitrotoluene (2,4-DNT) as a common industrial waste has been massively discharged into the environment with industrial wastewater. Due to its refractory degradation, high toxicity, and bioaccumulation, 2,4-DNT pollution has become increasingly serious. Compared with the currently available physical and chemical methods, in situ bioremediation is considered as an economical and environmentally friendly approach to remove toxic compounds from contaminated environment. In this study, we relocated a complete degradation pathway of 2,4-DNT into Escherichia coli to degrade 2,4-DNT completely. Eight genes from Burkholderia sp. strain were re-synthesized by PCR-based two-step DNA synthesis method and introduced into E. coli. Degradation experiments revealed that the transformant was able to degrade 2,4-DNT completely in 12 h when the 2,4-DNT concentration reached 3 mM. The organic acids in the tricarboxylic acid cycle were detected to prove the degradation of 2,4-DNT through the artificial degradation pathway. The results proved that 2,4-DNT could be completely degraded by the engineered bacteria. In this study, the complete degradation pathway of 2,4-DNT was constructed in E. coli for the first time using synthetic biology techniques. This research provides theoretical and experimental bases for the actual treatment of 2,4-DNT, and lays a technical foundation for the bioremediation of organic pollutants.
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Nitrobenzene is widely present in industrial wastewater and soil. Biodegradation has become an ideal method to remediate organic pollutants due to its low cost, high efficiency, and absence of secondary pollution. In the present study, 10 exogenous genes that can completely degrade nitrobenzene were introduced into Escherichia coli, and their successful expression in the strain was verified by fluorescence quantitative polymerase chain reaction and proteomic analysis. The results of the degradation experiment showed that the engineered strain could completely degrade 4 mM nitrobenzene within 8 h. The formation of intermediate metabolites was detected, and the final metabolites entered the E. coli tricarboxylic acid cycle smoothly. This process was discovered by isotope tracing method. Results indicated the integrality of the degradation pathway and the complete degradation of nitrobenzene. Finally, further experiments were conducted in soil to verify its degradation ability and showed that the engineered strain could also degrade 1 mM nitrobenzene within 10 h. In this study, engineered bacteria that can completely degrade nitrobenzene have been constructed successfully. The construction of remediation-engineered bacteria by synthetic biology laid the foundation for the industrial application of biological degradation of organic pollutants.
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Poluentes Ambientais , Escherichia coli , Bactérias/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Nitrobenzenos/metabolismo , Proteômica , SoloRESUMO
Bougainvillea spectabilis Willd. is an important ornamental flowering plant belonging to the family Nyctaginaceae. It is widely used in landscape designs in tropical and subtropical regions. In December 2020, severe disease-causing leaf spots were discovered on the leaves of B. spectabilis in the Modern Agricultural Park (110°19' E, 21°26' N) Zhanjiang City, Guangdong Province, China. Field surveys revealed that the disease was widespread, with an incidence of 60-80%. Early symptoms on the leaves appeared as tiny leaf spots that later developed into concentric circles surrounded by a yellowish halo (Fig. 1). Diseased leaves with typical symptoms were collected for pathogen isolation. The leading edges of the lesions were excised, sanitized in 75% ethanol for 30 s and in 3% sodium hypochlorite for 3 min, and rinsed three times with sterile distilled water (SDW). The diseased tissue was crushed in 1 mL SDW, soaked for 15 min, and then spread onto nutrient agar medium on a petri dish. Circular, bright yellow colonies with smooth margins were observed after 24 h of incubation at 28 °C. The isolate (SJM1) was a gram-negative bacillus with positive results for catalase, indole synthesis, maltose, and arbutin and negative results for sorbitol, lactose, salicin, and starch hydrolysis. The SJM1 genomic DNA was extracted using the TIANamp Bacterial DNA Kit, and partial 16S rDNA gene segments were amplified using the bacterial generic primers 27F and 1492R. The collated 16S rDNA gene sequences were submitted to the NCBI GenBank (MZ723935). BLAST analysis of the sequences revealed 99.38% identity with Pantoea stewartii (MG517424.1). Amplification using subspecies-specific primers galE (#562/564; Gehring et al. 2014), glmS (#356/341; Wensing et al. 2010), and pstC + pstS (#338/339; Wensing et al. 2010) revealed that the genes showed 99-100% identity with P. stewartii subsp. indologenes (galE = 100%, MZ754494.1; glmS = 99.79%, MZ75496.1; and pstC + pstS = 99.89%, MZ754495.1). Phylogenetic trees were constructed using the neighbor-joining method (MEGA X), with both the 16S rDNA sequence (Fig. 2 2A) and the concatenated 16S rDNA, galE, pstC + pstS, and glmS sequences (Fig.2 2B). The SJM1 isolate belonged to the same clade as P. stewartii subsp. indologenes and was 99% homologous to P. stewartii subsp. indologenes strain ZJ-FGZX1 (Fig. 2 2B; Ren et al. 2020). Pathogenicity tests were performed through prick wound inoculation. Sterile needles were used to create fresh wounds on healthy young leaves of one-year-old B. spectabilis plants. Wounds were inoculated with 20 µl bacterial suspension (1 × 108 CFU/ml) or SDW. Four leaves per plant and three plants per treatment were evaluated. The plants were incubated at 28 °C temperature and 80-90% relative humidity. After 4-7 days of inoculation, all plants inoculated with the bacterial suspension had spot symptoms with a halo, similar to those observed in the field. However, leaves inoculated with SDW alone did not show any symptoms. Furthermore, the colony morphology and 16S rDNA sequences of the strains isolated from the inoculated leaves were identical to those of the original isolates. These results verified Koch's postulates. Based on biochemical identification and sequencing analysis, the pathogen causing B. spectabilis leaf spot was identified as P. stewartii subsp. indologenes. Previous reports have shown that P. stewartii subsp. indologenes can cause diseases in Dracaena sanderiana, Cenchrus americanus, and Allium cepa (Zhang et al. 2020, Ashajyothi et al. 2021, Stumpf et al. 2018). To our knowledge, this is the first report of P. stewartii subsp. indologenes causing B. spectabilis leaf spot disease in China.
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Telemedicine is considered to be an important approach for medical education in rural areas. Due to a significant shortage of radiation oncologists in rural areas of Sichuan Province in China, a tele-radiotherapy system has been designed and developed for training radiation oncologists in the Sichuan Cancer Hospital and Research Institute. The whole process of the radiotherapy teaching platform was designed and established in the tele-radiotherapy system. A detailed radiation therapy process could be obtained in rural areas through the tele-radiotherapy system. Through the tele-radiotherapy system, oncologists in rural hospitals are trained at any time and anywhere. And the experience of experts in the Sichuan Cancer Hospital and Research Institute is effectively and quickly conveyed to rural areas. A tele-radiotherapy system is considered to be an important means to promote the level of radiotherapy and to solve the shortage of radiation oncologists in rural areas.
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Educação Médica , Radioterapia (Especialidade) , Telemedicina , China , Humanos , Radio-OncologistasRESUMO
The high toxicity of persistent pollutants limits the phytoremediation of pollutants-contaminated soil. In this study, heterologous expressing Halorhodospira halophila single-stranded DNA binding protein gene (HhSSB) improves tolerance to 2,4,6-trinitrotoluene (TNT), 2,4,6-trichlorophenol (2,4,6-TCP), and thiocyanate (SCN-) in A. thaliana and tall fescue (Festuca arundinacea). The HhSSB transformed Arabidopsis, and tall fescue also exhibited enhanced phytoremediation of TNT, 2,4,6-TCP, and SCN- separately contaminated soil and co-contaminated soil compared to control plants. TNT assay was selected to explore the mechanism of how HhSSB enhances the phytoremediation of persistent pollutants. Our result indicates that HhSSB enhances the phytoremediation of TNT by enhancing the transformation of TNT in Arabidopsis. Moreover, transcriptomics and comet analysis revealed that HhSSB improves TNT tolerance through three pathways: strengthening the defense system, enhancing the ROS scavenging system, and reducing DNA damage. These results presented here would be particularly useful for further studies in the remediation of soil contaminated by organic and inorganic pollutants.
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Poluentes Ambientais , Poluentes do Solo , Biodegradação Ambiental , Proteínas de Ligação a DNA , Halorhodospira halophila , SoloRESUMO
2,4,6-trinitrotoluene (TNT) and cobalt (Co) contaminants have posed a severe environmental problem in many countries. Phytoremediation is an environmentally friendly technology for the remediation of these contaminants. However, the toxicity of TNT and cobalt limit the efficacy of phytoremediation application. The present research showed that expressing the Acidithiobacillus ferrooxidans single-strand DNA-binding protein gene (AfSSB) can improve the tolerance of Arabidopsis and tall fescue to TNT and cobalt. Compared to control plants, the AfSSB transformed Arabidopsis and tall fescue exhibited enhanced phytoremediation of TNT and cobalt separately contaminated soil and co-contaminated soil. The comet analysis revealed that the AfSSB transformed Arabidopsis suffer reduced DNA damage than control plants under TNT or cobalt exposure. In addition, the proteomic analysis revealed that AfSSB improves TNT and cobalt tolerance by strengthening the reactive superoxide (ROS) scavenging system and the detoxification system. Results presented here serve as strong theoretical support for the phytoremediation potential of organic and metal pollutants mediated by single-strand DNA-binding protein genes. SUMMARIZES: This is the first report that AfSSB enhances phytoremediation of 2,4,6-trinitrotoluene and cobalt separately contaminated and co-contaminated soil.
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Cobalto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Poluentes do Solo/metabolismo , Trinitrotolueno/metabolismo , Acidithiobacillus/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Biodegradação Ambiental , Proteínas de Ligação a DNA/genética , Lolium/genética , Lolium/metabolismo , Plantas Geneticamente Modificadas/genética , ProteômicaRESUMO
Betanin has been widely used as an additive for many centuries, and its use has increased because of its market application as an additive, high free radical scavenging activity, and safety, health-promoting properties. The main source of betanin is red beet, but many factors notably affect the yield of betanin from red beets. Betanin is not produced in cereal grains. Thus, developing biofortified crops with betanin is another alternative to health-promoting food additives. Here, rice endosperm was bioengineered for betanin biosynthesis by introducing three synthetic genes (meloS, BvDODA1S, and BvCYP76AD1S). The overexpression of these genes driven by rice endosperm-specific promoter established the betanin biosynthetic pathways in the endosperm, resulting in new types of germplasm - 'Betanin Rice' (BR). The BR grains were enriched with betanin and had relatively high antioxidant activity. Our results proved that betanin can be biosynthesized de novo in rice endosperm by introducing three genes in the committed betanin biosynthetic pathway. The betanin-fortified rice in this study can be used as a functional grain to promote health and as a raw material to process dietary supplements.
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Endosperma , Oryza , Betacianinas , Grão Comestível , Endosperma/genética , Engenharia Metabólica , Oryza/genéticaRESUMO
By developing a 'two-crystal' method for color erasure, we can broaden the scope of chromatic interferometry to include optical photons whose frequency difference falls outside of the 400 nm to 4500 nm wavelength range, which is the passband of a PPLN crystal. We demonstrate this possibility experimentally, by observing interference patterns between sources at 1064.4 nm and 1063.6 nm, corresponding to a frequency difference of about 200 GHz.
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High-performance single-photon detectors (SPDs) at 1550-nm band are critical for fiber-based quantum communications. Among many types of SPDs, the up-conversion SPDs based on periodically poled lithium niobate waveguides are of great interest. Combined with a strong pump laser, the telecom single-photons are converted into short wavelength ones and detected by silicon-based SPDs. However, due to the difficulty of precise controlling waveguide profile, the direct coupling between a single-mode fiber and the waveguide is not efficient. Here by utilizing fiber taper with proper diameter, optimal mode-matching is achieved and coupling efficiency up to 93% is measured. With an optimized design, a system detection efficiency of 36% and noise counting rate of 90 cps are realized. The maximum detection efficiency is characterized as 40% with a noise counting rate of 200 cps. Numerical simulation results indicate that our device can significantly improve the performance of QKD and extend the communication distance longer than 200â km.
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Although glutathione S-transferase (GST, EC 2.5.1.18) is thought to play important roles in abiotic stress, limited information is available regarding the function of its gene in grapes. In this study, a GST gene from grape, VvGSTF13, was cloned and functionally characterized. Transgenic Arabidopsis plants containing this gene were normal in terms of growth and maturity compared with control plants but had enhanced resistance to salt, drought, and methyl viologen stress. The increased tolerance of the transgenic plants correlated with changes in activities of antioxidative enzymes. Our results indicate that the gene from grape plays a positive role in improving tolerance to salinity, drought, and methyl viologen stresses in Arabidopsis.
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Arabidopsis/metabolismo , Glutationa Transferase/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Estresse Fisiológico , Vitis/genética , Arabidopsis/genética , Secas , Glutationa Transferase/classificação , Glutationa Transferase/genética , Malondialdeído/metabolismo , Peroxidase/metabolismo , Filogenia , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal , Superóxido Dismutase/metabolismoRESUMO
Based on the technique of periodically poled lithium niobate waveguide, up-conversion single-photon detection at 1.064-µm is demonstrated. We have achieved a system photon detection efficiency of 32.5% with a very low noise count rate of 45 counts per second by pumping with a 1.55-µm-band single frequency laser using the long-wavelength pumping technique and exploiting volume Bragg grating as a narrow band filter. Replacing the volume Bragg grating with a combination of adequate dielectric filters, a detection efficiency of up to 38% with a noise count rate of 700 counts per second is achieved, making the overall system stable and practical. The up-conversion single-photon detector operating at 1.064 µm can be a promising robust counter and find usage in many fields.
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OBJECTIVE: To evaluate the safety, clinical efficacy, and long-term outcome of arsenic trioxide (As2 O3 ) intravenous infusion for pulmonary metastases in patients with HCC. MATERIALS AND METHODS: Sixty consecutive patients who were diagnosed with advanced hepatocellular carcinoma (HCC) with pulmonary metastasis were randomized 1:1 into the treatment and control groups. Treatment group underwent transcatheter arterial chemoembolization (TACE) for the primary liver tumor and then underwent As2 O3 treatment, whereas control group underwent TACE alone. The treatment group underwent a continuous 5-h intravenous infusion of 10 mg/day As2 O3 . The course of As2 O3 treatment was initiated 3-5 days after TACE (to allow liver and gastrointestinal function to recover) and continued for 14 consecutive days. All patients in the treatment group underwent at least four treatment courses. Response to treatment was evaluated after four treatment courses. RESULT: In treatment group, two patients had a complete response (CR), six had a partial response (PR), 10 had stable disease (SD), and 12 had progressive disease. A clinically effective rate (CR + PR) was achieved in 26.7%, and the clinical benefit rate (CR + PR + SD) was 60%. In the control group, no patients had a CR or PR, five had SD, and 25 had progressive disease. The clinically effective rate was 0%, and the clinical benefit rate was 16.7%. The overall 1-year survival was 56.7% in treatment group and 36.7% in control group. The overall 2-year survival was 16.7% in treatment group and 3.3% in control group. CONCLUSION: Transcatheter arterial chemoembolization plus an intravenous infusion of As2 O3 effectively controlled pulmonary metastasis and prolonged overall survival in patients with HCC compared with TACE alone.
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Antineoplásicos/administração & dosagem , Arsenicais/administração & dosagem , Quimioembolização Terapêutica , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Óxidos/administração & dosagem , Adulto , Trióxido de Arsênio , Terapia Combinada , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Neoplasias Hepáticas/mortalidade , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Fatores de Tempo , Resultado do TratamentoRESUMO
The plant-specific tau class of glutathione S-transferases (GSTs) is often highly stress-inducible and expressed in a tissue-specific manner, thereby suggesting its important protective roles. Although activities associated with the binding and transport of reactive metabolites have been proposed, little is known about the regulatory functions of GSTs. Expression of AtGSTU19 is induced by several stimuli, but the function of this GST remains unknown. In this study, we demonstrated that transgenic over-expressing (OE) plants showed enhanced tolerance to different abiotic stresses and increased percentage of seed germination and cotyledon emergence. Transgenic plants exhibited an increased level of proline and activities of antioxidant enzymes, along with decreased malonyldialdehyde level under stress conditions. Real-time polymerase chain reaction (PCR) analyses revealed that the expression levels of several stress-regulated genes were altered in AtGSTU19 OE plants. These results indicate that AtGSTU19 plays an important role in tolerance to salt/drought/methyl viologen stress in Arabidopsis.
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KEY MESSAGE: The ADI1 Arabidopsis plants enhanced tolerance and degradation efficiency to naphthalene and had great potential for phytoremediation of naphthalene in the plant material before composting or harvesting and removal. Naphthalene is a global environmental concern, because this substance is assumed to contribute considerably to human cancer risk. Cleaning up naphthalene contamination in the environment is crucial. Phytoremediation is an efficient technology to clean up contaminants. However, no gene that can efficiently degrade exogenous recalcitrant naphthalene in plants has yet been discovered. Ferredoxin (Fd) is a key player of biological electron transfer reaction in the PAH degradation process. The biochemical pathway for bacterial degradation of naphthalene has been well investigated. In this study, a rice gene, ADI1, which codes for a putative photosynthetic-type Fd, has been transformed into Arabidopsis thaliana. The transgenic Arabidopsis plants enhanced tolerance and degradation efficiency of naphthalene. Compared with wild-type plants, transgenic plants assimilated naphthalene from the culture media faster and removed more of this substance. When taken together, our findings suggest that breeding plants with overexpressed ADI1 gene is an effective strategy to degrade naphthalene in the environment.
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Arabidopsis/fisiologia , Ferredoxinas/genética , Naftalenos/metabolismo , Oryza/genética , Arabidopsis/genética , Biodegradação Ambiental , Ferredoxinas/metabolismo , Expressão Gênica , Fotossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente ModificadasRESUMO
Acrylamide (ACR) is a widely used industrial chemical. However, it is a dangerous compound because it showed neurotoxic effects in humans and act as reproductive toxicant and carcinogen in many animal species. In the environment, acrylamide has high soil mobility and may travel via groundwater. Phytoremediation is an effective method to remove the environmental pollutants, but the mechanism of plant response to acrylamide remains unknown. With the purpose of assessing remediation potentials of plants for acrylamide, we have examined acrylamide uptake by the model plant Arabidopsis grown on contaminated substrates with high performance liquid chromatography (HPLC) analysis. The result revealed that acrylamide could be absorbed and degraded by Arabidopsis. Further microarray analysis showed that 527 transcripts were up-regulated within 2-days under acrylamide exposure condition. We have found many potential acrylamide-induced genes playing a major role in plant metabolism and phytoremediation.