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1.
J Environ Manage ; 366: 121790, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003900

RESUMO

Oleaginous forests provide diverse ecosystem services, including timber, seed yield (a vital feedstock for biodiesel production), and substantial carbon savings. These carbon savings encompass carbon sequestration related to timber growth and carbon savings resulting from substituting fossil fuel with biodiesel. However, oleaginous forests are vulnerable to seed wasp attacks (disservice), which significantly threaten both seed yield and carbon savings. Using an integrated ecological-economic model that includes Faustmann's Land Expectation Value model and a pest damage control model, we aim to understand the intricate relationship among multiple ecosystem services and disservices of oleaginous forests. The results reveal four distinct phases contingent on varying pesticide application rates: the pesticide under-use phase, substitution phase, complementary phase, and over-use phase. Notably, a potential avenue to minimize pest damage is identified during the complementary phase by reducing the optimal rotation age at the expense of decreased carbon sequestration and bioenergy provision, posing a challenge to climate change mitigation. These findings have implications for formulating policies to manage conflicting ecosystem services of energy forests, offering valuable insights into the intersection of sustainable forest management and climate policy.


Assuntos
Biocombustíveis , Sequestro de Carbono , Mudança Climática , Ecossistema , Florestas
2.
Environ Sci Technol ; 57(32): 12010-12018, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506359

RESUMO

Determination of microplastics and nanoplastics (MNPs), especially small MPs and NPs (<150 µm), in solid environmental matrices is a challenging task due to the formation of stable aggregates between MNPs and natural colloids. Herein, a novel method for extracting small MPs and NPs embedded in soils/sediments/sludges has been developed by combining tetramethylammonium hydroxide (TMAH) digestion with dichloromethane (DCM) dissolution. The solid samples were digested with TMAH, and the collected precipitate was washed with anhydrous ethanol to eliminate the natural organic matter. Then, the MNPs in precipitate were extracted by dissolving in DCM under ultrasonic conditions. Under the optimized digestion and extraction conditions, the factors including sizes and concentrations of MNPs showed insignificant effects on the extraction process. The feasibility of this sample preparation method was verified by the satisfactory spiked recoveries (79.6-91.4%) of polystyrene, polyethylene, polypropylene, poly(methyl methacrylate), polyvinyl chloride, and polyethylene terephthalate MNPs in soil/sediment/sludge samples. The proposed sample preparation method was coupled with pyrolysis gas chromatography-mass spectrometry to determine trace small MPs and NPs with a relatively low detection limit of 2.3-29.2 µg/g. Notably, commonly used MNPs were successfully detected at levels of 4.6-51.4 µg/g in 6 soil/sediment/sludge samples. This proposed method is promising for evaluating small solid-embedded MNP pollution.


Assuntos
Microplásticos , Plásticos , Plásticos/análise , Cromatografia Gasosa-Espectrometria de Massas , Esgotos/química , Cloreto de Metileno/análise , Solubilidade , Solo/química , Digestão
3.
J Environ Sci (China) ; 128: 45-54, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36801041

RESUMO

The removal of iodide (I-) from source waters is an effective strategy to minimize the formation of iodinated disinfection by-products (DBPs), which are more toxic than their brominated and chlorinated analogues. In this work, a nanocomposite Ag-D201 was synthesized by multiple in situ reduction of Ag-complex in D201 polymer matrix, to achieve highly efficient removal of iodide from water. Scanning electron microscope /energy dispersive spectrometer characterization showed that uniform cubic silver nanoparticles (AgNPs) evenly dispersed in the D201 pores. The equilibrium isotherms data for iodide adsorption onto Ag-D201 was well fitted with Langmuir isotherm with the adsorption capacity of 533 mg/g at neutral pH. The adsorption capacity of Ag-D201 increased with the decrease of pH in acidic aqueous solution, and reached the maximum value of 802 mg/g at pH 2. This was attributed to the oxidization of I-, by dissolved oxygen under the catalysis of AgNPs, to I2 which was finally adsorbed as AgI3. However, the aqueous solutions at pH 7 - 11 could hardly affect the iodide adsorption. The adsorption of I- was barely affected by real water matrixes such as competitive anions (SO42-, NO3-, HCO3-, Cl-) and natural organic matter, of which interference of NOM was offset by the presence of Ca2+. The proposed synergistic mechanism for the excellent performance of iodide adsorption by the absorbent was ascribed to the Donnan membrane effect caused by the D201 resin, the chemisorption of I- by AgNPs, and the catalytic effect of AgNPs.


Assuntos
Nanopartículas Metálicas , Poluentes Químicos da Água , Água , Iodetos , Poliestirenos , Prata , Nanopartículas Metálicas/química , Poluentes Químicos da Água/química , Adsorção
4.
J Craniofac Surg ; 34(2): 669-673, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36184756

RESUMO

PURPOSE: The aim was to identify whether malignant diseases increase the risk of medication-related osteonecrosis of the jaw (MRONJ) occurrence when patients are exposed to bisphosphonate, antiresorptive or antiangiogenic drugs. To analyze related factors. METHODS: A systematic literature searching was performed in PubMed, Embase, and Google Scholar for studies with information about whether patients have malignant diseases. Patients involved must be treated with MRONJ-related drugs and at high risk of developing MRONJ. RESULTS: A total of 6 cohort studies and 3 case-control studies were included. Analysis according 9 studies shows that malignant diseases have significant influence on MRONJ occurrence (risk ratio (RR): 2.62; 95% confidence interval (95% CI): 1.58-4.33; P =0.0002). Subgroup analysis according 6 cohort studies also shows that malignant diseases significantly affect MRONJ occurrence (RR: 3.50; 95% CI: 1.63-7.52; P =0.001). Chemotherapy have no obvious influence on MRONJ occurrence (RR: 1.64; 95% CI: 0.79-3.39; P =0.18). Intravenous drug administration significantly influences MRONJ occurrence (RR: 2.67; 95% CI: 1.27-5.58; P =0.009). CONCLUSIONS: Patients with malignant diseases have higher risk of MRONJ occurrence when exposed to bisphosphonate, antiresorptive, or antiangiogenic drugs. Cumulative dosages from intravenous drugs administration contribute to MRONJ developing. Prevention of MRONJ in patients with malignancy should be emphasized.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Neoplasias , Humanos , Difosfonatos/efeitos adversos , Inibidores da Angiogênese
5.
PLoS One ; 17(6): e0269742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35704638

RESUMO

The current study aimed to explore the lncRNA-miRNA-mRNA networks associated with alcohol-related esophageal cancer (EC). RNA-sequencing and clinical data were downloaded from The Cancer Genome Atlas and the differentially expressed genes (DEGs), long non-coding RNAs (lncRNAs, DELs), and miRNAs (DEMs) in patients with alcohol-related and non-alcohol-related EC were identified. Prognostic RNAs were identified by performing Kaplan-Meier survival analyses. Weighted gene co-expression network analysis was employed to build the gene modules. The lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) networks were constructed based on our in silico analyses using data from miRcode, starBase, and miRTarBase databases. Functional enrichment analysis was performed for the genes in the identified ceRNA networks. A total of 906 DEGs, 40 DELs, and 52 DEMs were identified. There were eight lncRNAs and miRNAs each, including ST7-AS2 and miR-1269, which were significantly associated with the survival rate of patients with EC. Of the seven gene modules, the blue and turquoise modules were closely related to disease progression; the genes in this module were selected to construct the ceRNA networks. SNHG12-miR-1-ST6GAL1, SNHG3-miR-1-ST6GAL1, SPAG5-AS1-miR-133a-ST6GAL1, and SNHG12-hsa-miR-33a-ST6GA interactions, associated with the N-glycan biosynthesis pathway, may have key roles in alcohol-related EC. Thus, the identified biomarkers provide a novel insight into the molecular mechanism of alcohol-related EC.


Assuntos
Neoplasias Esofágicas , MicroRNAs , RNA Longo não Codificante , Proteínas de Ciclo Celular/metabolismo , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética
6.
Food Funct ; 12(12): 5621-5636, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34018494

RESUMO

Yellow tea, a rare type tea from China, has a rich breadth of functional ingredients and benefits the gastrointestinal tract. However, it is not clear whether the yellow tea extract can alleviate constipation. Therefore, we used loperamide-induced constipation in mice to evaluate the effects of yellow tea extract. Fifty Kunming mice were randomly divided into five groups: normal, model, low-dose yellow tea extract, low-dose yellow tea extract prevention group, and high-dose yellow tea extract prevention group. Mice were administered yellow tea extract for 5 weeks followed by loperamide-induced constipation for the final 2 weeks. The results showed that yellow tea extract alleviated constipation symptoms by improving the fecal water content, defecation weight, and gastrointestinal transit rate. Yellow tea extract intervention also protected colon tissue, regulated serum neurotransmitters, and decreased the vasoactive intestinal peptide level. Furthermore, qRT-PCR indicated that yellow tea extract regulated genes associated with the constipation state, raised 5-HT3 and 5-HT4 and reduced AQP3 and AQP4 mRNA expression. Moreover, we found that yellow tea extract changed the gut microbiota composition. Community diversity and richness were increased and principal co-ordinate analysis demonstrated that the yellow tea extract prophylaxis groups differed from the model group. Difference analysis indicated that yellow tea extract increased Roseburia, Lachnospiraceae_UCG-006, and Bifidobacterium and decreased norank_f_Clostridiales_vadinBB60_group, unclassified_o_Bacteroidales, and Bacteroides, which are correlated with constipation. Based on these results, we believe that regular yellow tea consumption can effectively alleviate constipation.


Assuntos
Constipação Intestinal/tratamento farmacológico , Loperamida/efeitos adversos , Extratos Vegetais/farmacologia , Chá/química , Animais , Aquaporina 3/metabolismo , Aquaporina 4/metabolismo , China , Colo/efeitos dos fármacos , Constipação Intestinal/induzido quimicamente , Modelos Animais de Doenças , Microbioma Gastrointestinal/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos
7.
EMBO Rep ; 22(4): e51298, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33594776

RESUMO

Notch signaling and epigenetic factors are known to play critical roles in regulating tissue homeostasis in most multicellular organisms, but how Notch signaling coordinates with epigenetic modulators to control differentiation remains poorly understood. Here, we identify heterochromatin protein 1c (HP1c) as an essential epigenetic regulator of gut homeostasis in Drosophila. Specifically, we observe that HP1c loss-of-function phenotypes resemble those observed after Notch signaling perturbation and that HP1c interacts genetically with components of the Notch pathway. HP1c represses the transcription of Notch target genes by directly interacting with Suppressor of Hairless (Su(H)), the key transcription factor of Notch signaling. Moreover, phenotypes caused by depletion of HP1c in Drosophila can be rescued by expressing human HP1γ, suggesting that HP1γ functions similar to HP1c in Drosophila. Taken together, our findings reveal an essential role of HP1c in normal development and gut homeostasis by suppressing Notch signaling.


Assuntos
Proteínas de Drosophila , Animais , Proteínas Cromossômicas não Histona/genética , Drosophila/genética , Proteínas de Drosophila/genética , Heterocromatina , Homeostase , Humanos , Receptores Notch/genética
8.
Pharm Biol ; 58(1): 561-573, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32615903

RESUMO

Context: The Chinese medicinal materials originate from animals, plants, or minerals must undergo appropriate treatment before use as decoction pieces. Processing of Chinese medicines with liquid excipients is a pharmaceutical technique that transforms medicinal raw materials into decoction pieces which are significantly different from the original form. During processing, significant changes occur in chemical constituents, which inevitably affects clinical efficacy. At present, the liquid materials in processing mainly involve wine, vinegar, honey, saline water, ginger juice, herbal juice, etc.Objective: This review introduces the typical methods of liquid excipients processing, summarizes the influence on chemical composition, pharmacological efficacy, and expounds the ways and mechanisms of liquid excipients to change the properties of drugs, enhance the efficacy, eliminate or reduce toxicity and adverse reaction.Methods: English and Chinese literature from 1986 to 2020 was collected from databases including Web of Science, PubMed, Elsevier, Chinese Pharmacopoeia 2015, and CNKI (Chinese). Liquid excipients, processing, pharmacological effects, synergism, chemical constitution, traditional Chinese medicine (TCM) were used as the key words.Results: Liquid excipients play a key role in the application of TCM. Processing with proper liquid excipients can change the content of toxic or active components by physical or chemical transformation, decrease or increase drug dissolution, alter drug pharmacokinetics, or exert their own pharmacological effects. Thus, processing with liquid excipients is essential to ensure the safety and efficacy of TCM in clinic.Conclusion: This article could be helpful for researchers who are interested in traditional Chinese herbs processed with liquid excipients.


Assuntos
Medicamentos de Ervas Chinesas/síntese química , Excipientes/síntese química , Medicina Tradicional Chinesa/métodos , Ácido Acético/síntese química , Animais , Mel , Humanos , Medicina Tradicional Chinesa/tendências , Óleos de Plantas/síntese química , Vinho
9.
Future Oncol ; 16(25): 1903-1909, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32449621

RESUMO

Aim: To investigate the expression and prognostic value of KRT 15 in esophageal carcinoma. Materials & methods: The expression levels of KRT 15 were measured in 128 cases of esophageal carcinoma and matched adjacent normal tissues by immunohistochemistry and Western blot assays. Results & conclusion: Western blot analysis shown the expression levels of KRT 15 in esophageal carcinoma were significantly higher compared with those in matched adjacent normal tissues (p < 0.001). immunohistochemistry result shown the high-expression rate of KRT 15 in esophageal carcinoma were 56.3%, which was significantly higher than those in normal tissues (35.9%; p = 0.002). KRT 15 high-expression correlated with T stage, lymph node metastasis, tumor node metastasis stage and prognosis (p < 0.05). These data indicate KRT 15 as a prognostic biomarker is highly expressed in esophageal carcinoma.


Assuntos
Biomarcadores Tumorais , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Expressão Gênica , Queratina-15/genética , Adulto , Idoso , Neoplasias Esofágicas/diagnóstico , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Queratina-15/metabolismo , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Curva ROC
10.
World J Clin Cases ; 8(3): 606-613, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32110673

RESUMO

BACKGROUND: Prostatic stromal sarcoma presenting with rhabdoid features is extremely rare, and only four cases have been reported in the English-language literature to date. Accordingly, there is no absolute definition of this group of tumors as yet, and our overall understanding of its morphological features, therapeutic regimen and prognosis is limited. CASE SUMMARY: A 34-year-old male patient was referred to our hospital to address a 2-mo history of hematuria and progressive dysuria. Pelvic computed tomography scan revealed a 6.0 cm × 5.2 cm × 7.2 cm mass in the prostate, with bladder invasion. The patient underwent transurethral prostatectomy as upfront therapy. He refused further treatment and died of uncontrollable tumor growth 3 mo after surgery. Pathology analysis revealed the stroma to be pleomorphic, with a huge number of atypical spindle cells. Rhabdomyoblastic cells, with abundant eosinophilic cytoplasm, were detected. The spindle cells were positive for vimentin, INI1 and ß-catenin, and the rhabdomyoblastic cells were positive for MyoD1, myogenin and INI1. The spindle cells and epithelial cells were sporadically positive for P53. CONCLUSION: The prostatic stromal sarcoma tumor was immunoreactive for ß-catenin, suggesting a role for the Wnt/ß-catenin pathway in this tumor type.

11.
BMC Cancer ; 19(1): 1064, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703631

RESUMO

BACKGROUND: The present standard of surgical treatment for esophageal cancer is country dependent. The aim of the present study was to investigate the basic aspects of surgical procedures performed for esophageal cancer, and provide information about the present state of esophageal cancer surgery in China. METHODS: Data were obtained from a database administered by the Chinese Ministry for Health. A total of 542 participating hospitals were divided into seven geographic areas, and 10% of hospitals in each area were randomly chosen for inclusion. All patients with esophageal cancer, who underwent esophagectomy in these participating hospitals from January 1 to December 31, 2015, were included in the present study. The clinical characteristics, stage of tumor at diagnosis, operation summary and outcomes, and histological findings of patients were extracted and analyzed. RESULTS: The present study included 11,791 patients, and the average number of patients per hospital was 218. Squamous cell carcinoma was the most common pathological type, while the mid-esophagus was the most common location. Open procedures were performed in 63.8% of patients, while minimally invasive esophagectomy was performed in 36.2% of patients. Multiple approaches to transthoracic esophagectomy were utilized. Two-field lymphadenectomy was the most frequently performed (64.8%), followed by three-field lymphadenectomy (21.8%). Gastric tubes, thoracic duct ligation and postoperative enteral nutrition were implemented to minimize complications. CONCLUSION: The standard operative procedure and detailed technique for esophageal carcinoma surgery is presently being debated in China. This survey provides some basic information about the present state of esophageal cancer surgery countrywide.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Excisão de Linfonodo/métodos , Idoso , China , Bases de Dados Factuais , Nutrição Enteral , Esofagectomia/efeitos adversos , Feminino , Humanos , Excisão de Linfonodo/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
12.
J Genet Genomics ; 46(4): 213-220, 2019 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-31060819

RESUMO

Gene expression regulation, including loss-of-function and gain-of-function assays, is a powerful method to study developmental and disease mechanisms. Drosophila melanogaster is an ideal model system particularly well-equipped with many genetic tools. In this review, we describe and discuss the gene expression regulation techniques recently developed and their applications, including the CRISPR/Cas9-triggered heritable mutation system, CRISPR/dCas9-based transcriptional activation (CRISPRa) system, and CRISPR/dCas9-based transcriptional repression (CRISPRi) system, as well as the next-generation transgenic RNAi system. The main purpose of this review is to provide the fly research community with an updated summary of newly developed gene expression regulation techniques and help the community to select appropriate methods and optimize the research strategy.


Assuntos
Drosophila melanogaster/genética , Engenharia Genética/métodos , Animais , Sistemas CRISPR-Cas/genética , Expressão Gênica , Interferência de RNA , Ativação Transcricional
13.
J Genet Genomics ; 46(1): 19-30, 2019 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-30745214

RESUMO

In the Drosophila ovary, escort cells (ECs) extrinsically control germline stem cell (GSC) maintenance and progeny differentiation. However, the underlying mechanisms remain poorly understood. In this study, we identified 173 EC genes for their roles in controlling GSC maintenance and progeny differentiation by using an in vivo systematic RNAi approach. Of the identified genes, 10 and 163 are required in ECs to promote GSC maintenance and progeny differentiation, respectively. The genes required for progeny differentiation fall into different functional categories, including transcription, mRNA splicing, protein degradation, signal transduction and cytoskeleton regulation. In addition, the GSC progeny differentiation defects caused by defective ECs are often associated with BMP signaling elevation, indicating that preventing BMP signaling is a general functional feature of the differentiation niche. Lastly, exon junction complex (EJC) components, which are essential for mRNA splicing, are required in ECs to promote GSC progeny differentiation by maintaining ECs and preventing BMP signaling. Therefore, this study has identified the major regulators of the differentiation niche, which provides important insights into how stem cell progeny differentiation is extrinsically controlled.


Assuntos
Diferenciação Celular/genética , Redes Reguladoras de Genes , Interferência de RNA , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Genes Essenciais/genética , Genômica , Mutação , Ovário/citologia , Ovário/metabolismo , Fenótipo , Splicing de RNA , Transdução de Sinais/genética
15.
J Invest Surg ; 32(3): 245-254, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29252044

RESUMO

PURPOSE: Intramedullary nailing (IMN) is a popular method in the management of femoral shaft fractures (FSFs). However, whether the association of IMN with pulmonary fat emboli can compromise the pulmonary and nervous systems is debatable. The purpose of this study is to compare IMN with the locked dual plating (LDP) method by assessing the clinical outcomes of FSF patients with head or chest injury. METHOD: A total of 126 FSF patients were included in this study between January 2010 and July 2016 and divided into LDP and IMN groups. Patient demographic characteristics, operative time, blood loss, Harris Hip Score, Lysholm Knee Score, radiological outcomes, and systemic complications were collected and compared between the two treatment groups. Patients were followed up for at least 12 months. RESULTS: The LDP group performed better than IMN in terms of operative time, estimated blood loss amount, and malunion rate. Differences in function scores, fracture union rate, overall pulmonary complication rate, and in-hospital mortality between the two groups were not significant. Average radiographic union time was significantly longer in the LDP group (36.3 weeks) than in the IMN group (32.5 weeks). One case of fixation failure occurred postoperatively in the LDP group, whereas one case of fracture nonunion took place in the IMN group. CONCLUSION: Our findings suggest that dual-plating fixation is a promising method for FSFs with multiple injuries. However, the retrospective nature of this study necessitates high-quality trials to be performed to assess the clinical efficiency of dual plating.


Assuntos
Fixação Intramedular de Fraturas , Traumatismo Múltiplo , Placas Ósseas , Humanos , Estudos Retrospectivos , Resultado do Tratamento
16.
Nanoscale ; 11(5): 2179-2185, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30346003

RESUMO

Newly emerging two-dimensional transition metal dichalcogenide HfS2 has received considerable attention recently due to its ultrahigh photoresponsivity, well-balanced carrier mobility and an appropriate band gap which offer potential in electronic and optoelectronic devices. In this work, HfS2 flakes up to 200 layers with varying color contrasts are fabricated and transferred on a SiO2/Si substrate. The Raman intensities of HfS2 flakes and Raman intensities of molecules adsorbed on HfS2 flakes are quantitatively studied both theoretically and experimentally by considering an optical interference effect. The effects of the main experimental factors: thickness of SiO2 and excitation wavelength on Raman intensities are also theoretically investigated. Due to the low absorption of HfS2, many strong high-order interference-induced enhancement peaks are observed which are different from high absorption materials like graphene and MoS2, in which only 2-4 interference-induced enhancement peaks exist. Due to the environmental instability of single layer HfS2 under ambient conditions, multi-layer HfS2 is a better choice than single layer HfS2 as a Raman scattering substrate which has a stronger Raman enhancement and a better environmental stability. The discovery here will expand the application of HfS2 flakes in molecular detection.

17.
Bio Protoc ; 9(2): e3141, 2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33654886

RESUMO

In recent years, great progress has been made in the research of genome editing systems, one of which is the CRISPR-Cas9 system, a powerful technology that is applied to edit animal genome. Here, we describe a CRISPR-Cas9 mediated mutation protocol for efficiently and specifically editing genes in Drosophila. In this optimized system, the mutant progeny can be generated by only injecting a DNA plasmid encoding synthetic guide RNA (sgRNA) under the control of the U6b promoter into transgenic fly embryos in which Cas9 is specifically expressed in the progenitor cells, thus the gene of interest can be edited by the CRISPR in germ cells, with high rate of heritable mutations and few side effects.

18.
Bio Protoc ; 9(2): e3147, 2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33654892

RESUMO

Powerful and general methods that can enhance gene expression are useful to systematically study gene function. To date, compared with the methods in generating loss-of-function mutants, methods to achieve gain-of-function are limited. The entire field in Drosophila has relied heavily on the Gal4/UAS:cDNA overexpression system developed over two decades ago. It is laborious and expensive to clone the coding DNA sequence (CDS) of a gene, especially those of large size. In addition, side effects of this method are often observed because of the ectopic expression. Also, simultaneous activation of two genes with the traditional method is often time-consuming, and few are achievable for three or more genes. In this protocol, we describe how to build an effective and convenient targeting activator system, flySAM, to activate endogenous genes in Drosophila melanogaster based on the structure-guided engineering of CRISPR-Cas9 complex.

19.
Bio Protoc ; 9(3): e3158, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33654966

RESUMO

Much of our knowledge about the mechanisms underlying biological processes relies on genetic approaches, whereby gene activity is reduced and the phenotypic consequences of perturbation are analyzed in detail. For functional genomic studies, a specific, systematic, and cost-effective manner is critical. Transgenic RNAi system is the top priority choice to study gene functions due to its simple and practical characteristics in Drosophila. We established a novel system that works well in both soma and germ cells which is efficient and specific. With this system, we can precisely and efficiently modulate highly expressed genes, and simultaneously knock down multiple genes in one step. In this study, we provide a detailed protocol of the pNP system, which replaces other transgenic systems, and expect it can provide some help to researchers who are using this system.

20.
Bio Protoc ; 9(24)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38156295

RESUMO

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