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1.
Nano Lett ; 24(10): 3133-3141, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477056

RESUMO

Liquid manipulation is essential for daily life and modern industry, and it is widely used in various fields, including seawater desalination, microfluidic robots, and biomedical engineering. Nevertheless, the current research focuses on the manipulation of individual droplets. There are a few projects for water film management. Here, we proposed a facile method of wind-triggered water film self-sculpturing based on a heterogeneous wettability surface, which is achieved by the femtosecond laser direct writing technology and femtosecond laser deposition. Under the conditions of various airflow velocities and water film thicknesses, three distinct behaviors of the water film were analyzed. As a result, when the water film thickness is lower than 4.9 mm, the self-sculpture process will occur until the whole superhydrophobic surface dewetting. Four potential applications are demonstrated, including encryption, oil containers, reconfigurable patterning, and self-splitting devices. This work provides a new approach for manipulating a water film of fluid control engineering.

2.
Int J Hyperthermia ; 41(1): 2365974, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38880503

RESUMO

PURPOSE: To investigate the feasibility, safety and efficacy of high intensity focused ultrasound ablation (HIFU) as a preoperative treatment for challenging hysteroscopic myomectomies. MATERIALS AND METHODS: A total of 75 patients diagnosed with types 0-III of uterine fibroids were enrolled. Based on the Size, Topography, Extension of the base, Penetration and lateral Wall position (STEPW) classification scoring system, 25 cases with a score ≥ 5 points were treated with HIFU followed by hysteroscopic myomectomy (HIFU + HM group), whereas 50 cases with a score < 5 points were treated with hysteroscopic myomectomy (HM group). RESULTS: The median preoperative STEPW score was 7 in the HIFU + HM group and 2 in the HM group. The average non-perfused volume (NPV) ratio achieved in fibroids after HIFU was 86.87%. Patients in the HIFU + HM group underwent hysteroscopic myomectomy one to four days after HIFU, and downgrading was observed in 81.81% of fibroids. The operation time for patients in the HIFU + HM group was 73 min and the success rate of myomectomy in a single attempt was 60%. The volume of distention medium used during the operation was greater in the HIFU + HM group than in the HM group (15,500 ml vs. 7500 ml). No significant difference was observed between the two groups in terms of intraoperative blood loss, the incidence of intraoperative and postoperative complications, menstrual volume score, or uterine fibroid quality of life score. CONCLUSION: HIFU can be utilized as a preoperative treatment for large submucosal fibroids prior to hysteroscopic myomectomy. HIFU offers a novel approach in the management of this subset of patients.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Histeroscopia , Leiomioma , Miomectomia Uterina , Humanos , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Adulto , Miomectomia Uterina/métodos , Histeroscopia/métodos , Pessoa de Meia-Idade , Leiomioma/cirurgia , Leiomioma/terapia , Estudos de Viabilidade , Resultado do Tratamento , Neoplasias Uterinas/cirurgia
3.
Nano Lett ; 23(11): 4947-4955, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37255233

RESUMO

Droplet steering has important applications in biomedical detection, local chemical reactions, liquid collection, and microfluidic control. Presently, droplet steering methods typically require specific paths and can be challenging to operate, involving complex fabrications for the operating systems. Here, we show a magnetically actuated superhydrophilic robot sphere (MSR) based on femtosecond laser direct writing technology for droplet steering. Through femtosecond laser treatment, uniform micro-/nanostructures are constructed on the surface of a MSR. Additionally, the contactless magnetic actuator makes it possible to remotely steer the MSR to transport droplets. After preliminary exploration of the mechanism by which MSR drives the droplet movement, the ability of MSR to control the droplet movement was systematically tested and analyzed. Moreover, the applications of the MSR in complex path liquid collection and transport, three-dimensional space transport, self-cleaning, etc., are further verified. This strategy provides a novel and reliable path for droplet manipulation and broadens its application.

4.
Int J Hyperthermia ; 40(1): 2197574, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37031960

RESUMO

OBJECTIVE: To compare the clinical efficacy of High intensity-focused ultrasound(HIFU) for different types of adenomyosis classified by magnetic resonance imaging (MRI). METHODS: A total of 227 patients with adenomyosis who underwent HIFU treatment in Suining Central Hospital from January 2014 to December 2019 were included. Based on the preoperative pelvic MRI examination and Kishi isometric classification method, the patients were divided into 4 types according to the location of lesions. There were 82 cases of type I (endogenous type), 75 cases of type II (exogenous type), 34 cases of type III (nodular type), and 36 cases of type IV (heterogeneous type). The results of HIFU treatment for four types of adenomyosis and intraoperative adverse effects were analyzed. The changes of lesion size, dysmenorrhea, and menstrual volume were analyzed at 3 and 6 months after the operation. RESULT: (1) adverse effects: All patients successfully accepted HIFU treatment under sedation and analgesia. Grade A adverse effects occurred in 51 cases (22.47%) and grade B adverse effects in 3 cases (1.32%). The incidence of adverse effects in type I-IV patients was 21.95%, 22.66%, 23.53%, and 30.56%, respectively. There was no significant difference in the incidence of grade A and B adverse effects in all types, and no grade C-F adverse effects occurred. (2) Ablation effect: The ablation rate of type III(nodular type)patients was (74.7 ± 20.3) %, which was significantly higher than that of the other three types (p < .05). (3) Changes in lesion size: the lesion size of all patients decreased after treatment and the reduction rate gradually increased with time. At 6 months after the operation, the lesion reduction rate of type III patients was (70.8 ± 14.8) %, higher than that of the other three types patients (p < .05). There was no significant difference in the reduction rate of type I, type II and type IV. (4) Remission of menorrhagia: At 6 months after the operation, the total remission rate of type III patients was 100%, while the total remission rate of type IV patients (65.4%, 17/26) that was lower than that of type I, II and III patients(p < .05). (5) Dysmenorrhea relief: At 6 months after the operation, the total dysmenorrhea relief rate of type III patients was 100% and the complete relief rate (28.1%, 18/31) was higher than that of the other three types, which was significant differences (p < .05). CONCLUSIONS: HIFU is safe and effective in the treatment of different types of adenomyosis, the therapeutic effect of HIFU in patients with type III adenomyosis is better than that of the other three types.


Assuntos
Adenomiose , Ablação por Ultrassom Focalizado de Alta Intensidade , Menorragia , Feminino , Humanos , Dismenorreia/diagnóstico por imagem , Dismenorreia/terapia , Dismenorreia/etiologia , Adenomiose/diagnóstico por imagem , Adenomiose/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Menorragia/cirurgia , Resultado do Tratamento , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
5.
Int J Hyperthermia ; 38(1): 282-287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33612045

RESUMO

OBJECTIVE: To explore the feasibility of high-intensity focused ultrasound (HIFU) ablation for treating metastatic pelvic tumors and recurrent ovary cancer. MATERIALS AND METHODS: Eight patients with metastatic pelvic tumors or recurrent ovary cancer were enrolled in this study. Among them, 5 patients had ovarian cancer, 1 had cervical cancer, 1 had endometrial cancer, and 1 had rectal cancer. Six of them received abdominal surgical operation for their primary cancer, no one received radiotherapy. HIFU treatment was performed under conscious sedation. Vital signs were monitored during the procedure, and adverse effects were recorded. Postoperative follow-up was performed to observe pain relief and the improvement of the patient's quality of life. RESULTS: The median age of the patients was 54 (range: 33-76) years, with a total of 12 lesions. The average volume of the lesions was 238.0 cm3. Six patients completed 12 months follow-up. Postoperative pain relief rate was 60% (3/5), and the quality of life improved in the short term. The main adverse effect of HIFU was pain in the treated area, with the pain score lower than 4, and all of which was self-relieved within 1 day after HIFU treatment. No serious complications such as skin burn, intestinal perforation, and nerve injury occurred. CONCLUSION: HIFU is feasible for the treatment of metastatic pelvic tumors or recurrent ovary cancer without serious complications. Therefore, HIFU seems a promising treatment for recurrent ovary cancer, metastatic pelvic tumors from cervical cancer, endometrial cancer, and rectal cancer.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Ovarianas , Neoplasias Pélvicas , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Qualidade de Vida , Resultado do Tratamento
6.
Nat Methods ; 8(9): 737-43, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21985007

RESUMO

We demonstrate the versatility of a collection of insertions of the transposon Minos-mediated integration cassette (MiMIC), in Drosophila melanogaster. MiMIC contains a gene-trap cassette and the yellow+ marker flanked by two inverted bacteriophage ΦC31 integrase attP sites. MiMIC integrates almost at random in the genome to create sites for DNAmanipulation. The attP sites allow the replacement of the intervening sequence of the transposon with any other sequence through recombinase-mediated cassette exchange (RMCE). We can revert insertions that function as gene traps and cause mutant phenotypes to revert to wild type by RMCE and modify insertions to control GAL4 or QF overexpression systems or perform lineage analysis using the Flp recombinase system. Insertions in coding introns can be exchanged with protein-tag cassettes to create fusion proteins to follow protein expression and perform biochemical experiments. The applications of MiMIC vastly extend the D. melanogaster toolkit.


Assuntos
Elementos de DNA Transponíveis/genética , Drosophila melanogaster/genética , Animais , Bioengenharia , Proteínas de Drosophila/genética , Regulação da Expressão Gênica , Íntrons , Mutagênese Insercional , Proteínas Recombinantes de Fusão/análise , Sequências Repetitivas de Ácido Nucleico
7.
Nanoscale ; 16(15): 7341-7362, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38511991

RESUMO

Crude oil is one of the most widely used energy and industrial raw materials that is crucial to the world economy, and is used to produce various petroleum products. However, crude oil often spills during extraction, transportation and use, causing negative impacts on the environment. Thus, there is a high demand for products to remediate leaked crude oil. Among them, oleophilic and hydrophobic adsorbents can absorb crude oil through thermal effects and are research hotspots. In this review, we first present an overview of wettability theory, the heating principles of various thermal effects, and the theory of reducing crude oil viscosity by heating. Then we discuss adsorbents based on different heating methods including the photothermal effect, Joule heating effect, alternating magnetic field heating effect, and composite heating effect. Preparation methods and oil adsorption performance of adsorbents are summarized. Finally, the advantages and disadvantages of various heating methods are briefly summarized, as well as the prospects for future research.

8.
ACS Appl Mater Interfaces ; 15(25): 30902-30912, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317029

RESUMO

A droplet triboelectric nanogenerator (TENG) has great potential for harvesting the high entropy energy in water. Despite extensive research, it still suffers from low average power density, poor long-term stability, and insufficient flexibility. Here, a porous micronanostructured polytetrafluoroethylene (PTFE) with superhydrophobicity and self-cleaning ability, is generated by femtosecond laser direct processing. The droplet TENG with laser treated PTFE (LT-PTFE) dielectric layer (L-DTENG) can reach a higher output compared with the droplet TENG with a PTFE dielectric layer (P-DTENG). L-DTENG also demonstrated good long-term stability, self-cleaning ability, and flexibility, making it suitable for various applications, including those involving dust and sewage pollution, as well as bending and pressing conditions. Furthermore, a simulation of finite element method (FEM) and an equivalent circuit model are established to understand the working mechanism of L-DTENG. This multifunctional device and theoretical research provide a smart strategy to generate electricity in a complex environment and lay a solid foundation for droplet TENG applications on a large scale.

9.
Nat Methods ; 6(6): 431-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19465919

RESUMO

We constructed Drosophila melanogaster bacterial artificial chromosome libraries with 21-kilobase and 83-kilobase inserts in the P[acman] system. We mapped clones representing 12-fold coverage and encompassing more than 95% of annotated genes onto the reference genome. These clones can be integrated into predetermined attP sites in the genome using UC31 integrase to rescue mutations. They can be modified through recombineering, for example, to incorporate protein tags and assess expression patterns.


Assuntos
Animais Geneticamente Modificados/genética , Mapeamento Cromossômico/métodos , Cromossomos Artificiais Bacterianos/genética , Clonagem Molecular/métodos , Drosophila melanogaster/genética , Biblioteca Gênica , Animais , Sequência de Bases , Dados de Sequência Molecular
10.
Nanoscale ; 14(26): 9392-9400, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35730522

RESUMO

On account of their wide range of applications in self-cleaning, anti-icing, frost suppression, etc., superhydrophobic surfaces have attracted considerate attention. However, most of the superhydrophobic surfaces can only be prepared on the surfaces of specific materials and are easily damaged in the case of friction. In this work, we propose a facile method to achieve superhydrophobicity on various substrate surfaces. By femtosecond laser direct processing, micron-level grooves and protrusions are constructed on substrates to form a protective layer. Then, the substrates covered by polytetrafluoroethylene (PTFE) were scanned to make the surfaces of the substrates superhydrophobic. Since the PTFE micro-nano-particles are evenly distributed on the grooves and protrusions, the surfaces exhibit robust superhydrophobicity with excellent anti-friction performance that is independent of the substrate properties. This work provides an efficient and environmentally friendly path for achieving robust superhydrophobic surfaces on various substrates.

11.
Sci Rep ; 9(1): 15840, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676813

RESUMO

The development of a simple fluorescent sensor for detecting the Pb2+ heavy metal is fundamentally important. The CH3NH3PbBr3 perovskite material exhibits excellent photoluminescence properties that are related to Pb2+. Based on the effects of Pb2+ on the luminescent properties of CH3NH3PbBr3, we design a novel platform for the selective fluorescence detection of Pb2+ ions. Herein, we use a CH3NH3Br solution at a high concentration as the fluorescent probe. Incorporation of PbBr2 into the CH3NH3Br solution results in a rapid chemical reaction to form CH3NH3PbBr3. Hence, the nonfluorescent CH3NH3Br material displays a sensitive and selective luminescent response to Pb2+ under UV light illumination. Moreover, the reaction between CH3NH3Br and PbBr2 could transform Pb2+ into CH3NH3PbBr3, and therefore, CH3NH3Br may also be used to extract Pb2+ from liquid waste in recycling applications.

12.
Elife ; 82019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674908

RESUMO

We previously reported a CRISPR-mediated knock-in strategy into introns of Drosophila genes, generating an attP-FRT-SA-T2A-GAL4-polyA-3XP3-EGFP-FRT-attP transgenic library for multiple uses (Lee et al., 2018a). The method relied on double stranded DNA (dsDNA) homology donors with ~1 kb homology arms. Here, we describe three new simpler ways to edit genes in flies. We create single stranded DNA (ssDNA) donors using PCR and add 100 nt of homology on each side of an integration cassette, followed by enzymatic removal of one strand. Using this method, we generated GFP-tagged proteins that mark organelles in S2 cells. We then describe two dsDNA methods using cheap synthesized donors flanked by 100 nt homology arms and gRNA target sites cloned into a plasmid. Upon injection, donor DNA (1 to 5 kb) is released from the plasmid by Cas9. The cassette integrates efficiently and precisely in vivo. The approach is fast, cheap, and scalable.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Técnicas de Introdução de Genes/métodos , Recombinação Homóloga , Mutagênese Insercional/métodos , Animais , DNA/genética , DNA de Cadeia Simples/genética , Drosophila
13.
Elife ; 72018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30091705

RESUMO

We generated two new genetic tools to efficiently tag genes in Drosophila. The first, Double Header (DH) utilizes intronic MiMIC/CRIMIC insertions to generate artificial exons for GFP mediated protein trapping or T2A-GAL4 gene trapping in vivo based on Cre recombinase to avoid embryo injections. DH significantly increases integration efficiency compared to previous strategies and faithfully reports the expression pattern of genes and proteins. The second technique targets genes lacking coding introns using a two-step cassette exchange. First, we replace the endogenous gene with an excisable compact dominant marker using CRISPR making a null allele. Second, the insertion is replaced with a protein::tag cassette. This sequential manipulation allows the generation of numerous tagged alleles or insertion of other DNA fragments that facilitates multiple downstream applications. Both techniques allow precise gene manipulation and facilitate detection of gene expression, protein localization and assessment of protein function, as well as numerous other applications.


Assuntos
Drosophila/genética , Entomologia/métodos , Marcação de Genes/métodos , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Genes Reporter , Integrases/metabolismo , Mutagênese Insercional
14.
Elife ; 72018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29565247

RESUMO

We generated a library of ~1000 Drosophila stocks in which we inserted a construct in the intron of genes allowing expression of GAL4 under control of endogenous promoters while arresting transcription with a polyadenylation signal 3' of the GAL4. This allows numerous applications. First, ~90% of insertions in essential genes cause a severe loss-of-function phenotype, an effective way to mutagenize genes. Interestingly, 12/14 chromosomes engineered through CRISPR do not carry second-site lethal mutations. Second, 26/36 (70%) of lethal insertions tested are rescued with a single UAS-cDNA construct. Third, loss-of-function phenotypes associated with many GAL4 insertions can be reverted by excision with UAS-flippase. Fourth, GAL4 driven UAS-GFP/RFP reports tissue and cell-type specificity of gene expression with high sensitivity. We report the expression of hundreds of genes not previously reported. Finally, inserted cassettes can be replaced with GFP or any DNA. These stocks comprise a powerful resource for assessing gene function.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Biblioteca Gênica , Fatores de Transcrição/genética , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Perfilação da Expressão Gênica , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Mutagênese Insercional , Especificidade de Órgãos/genética , Fatores de Transcrição/metabolismo
15.
Cell Host Microbe ; 21(6): 719-730.e6, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28579255

RESUMO

Clearance of bacteria by macrophages involves internalization of the microorganisms into phagosomes, which are then delivered to endolysosomes for enzymatic degradation. These spatiotemporally segregated processes are not known to be functionally coupled. Here, we show that lysosomal degradation of bacteria sustains phagocytic uptake. In Drosophila and mammalian macrophages, lysosomal dysfunction due to loss of the endolysosomal Cl- transporter ClC-b/CLCN7 delayed degradation of internalized bacteria. Unexpectedly, defective lysosomal degradation of bacteria also attenuated further phagocytosis, resulting in elevated bacterial load. Exogenous application of bacterial peptidoglycans restored phagocytic uptake in the lysosomal degradation-defective mutants via a pathway requiring cytosolic pattern recognition receptors and NF-κB. Mammalian macrophages that are unable to degrade internalized bacteria also exhibit compromised NF-κB activation. Our findings reveal a role for phagolysosomal degradation in activating an evolutionarily conserved signaling cascade, which ensures that continuous uptake of bacteria is preceded by lysosomal degradation of microbes.


Assuntos
Bactérias/imunologia , Imunidade Inata/imunologia , Lisossomos/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Fagocitose/fisiologia , Animais , Citocinas/metabolismo , Drosophila/imunologia , Escherichia coli/imunologia , Escherichia coli/patogenicidade , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Mutação , NF-kappa B/metabolismo , Fagossomos/metabolismo , Células RAW 264.7 , Transdução de Sinais/fisiologia
16.
Genetics ; 167(2): 761-81, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15238527

RESUMO

The Berkeley Drosophila Genome Project (BDGP) strives to disrupt each Drosophila gene by the insertion of a single transposable element. As part of this effort, transposons in >30,000 fly strains were localized and analyzed relative to predicted Drosophila gene structures. Approximately 6300 lines that maximize genomic coverage were selected to be sent to the Bloomington Stock Center for public distribution, bringing the size of the BDGP gene disruption collection to 7140 lines. It now includes individual lines predicted to disrupt 5362 of the 13,666 currently annotated Drosophila genes (39%). Other lines contain an insertion at least 2 kb from others in the collection and likely mutate additional incompletely annotated or uncharacterized genes and chromosomal regulatory elements. The remaining strains contain insertions likely to disrupt alternative gene promoters or to allow gene misexpression. The expanded BDGP gene disruption collection provides a public resource that will facilitate the application of Drosophila genetics to diverse biological problems. Finally, the project reveals new insight into how transposons interact with a eukaryotic genome and helps define optimal strategies for using insertional mutagenesis as a genomic tool.


Assuntos
Elementos de DNA Transponíveis/genética , Drosophila/genética , Genes de Insetos/genética , Genoma , Animais , Modelos Genéticos
17.
Elife ; 42015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25824290

RESUMO

Here, we document a collection of ∼7434 MiMIC (Minos Mediated Integration Cassette) insertions of which 2854 are inserted in coding introns. They allowed us to create a library of 400 GFP-tagged genes. We show that 72% of internally tagged proteins are functional, and that more than 90% can be imaged in unfixed tissues. Moreover, the tagged mRNAs can be knocked down by RNAi against GFP (iGFPi), and the tagged proteins can be efficiently knocked down by deGradFP technology. The phenotypes associated with RNA and protein knockdown typically correspond to severe loss of function or null mutant phenotypes. Finally, we demonstrate reversible, spatial, and temporal knockdown of tagged proteins in larvae and adult flies. This new strategy and collection of strains allows unprecedented in vivo manipulations in flies for many genes. These strategies will likely extend to vertebrates.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Biblioteca Gênica , Mutagênese Insercional , Interferência de RNA , Animais , Animais Geneticamente Modificados , Western Blotting , Encéfalo/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Larva/genética , Larva/metabolismo , Aprendizagem/fisiologia , Microscopia Confocal , Fatores de Tempo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , alfa Catenina/genética , alfa Catenina/metabolismo
18.
Genetics ; 188(3): 731-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21515576

RESUMO

The Drosophila Gene Disruption Project (GDP) has created a public collection of mutant strains containing single transposon insertions associated with different genes. These strains often disrupt gene function directly, allow production of new alleles, and have many other applications for analyzing gene function. Here we describe the addition of ∼7600 new strains, which were selected from >140,000 additional P or piggyBac element integrations and 12,500 newly generated insertions of the Minos transposon. These additions nearly double the size of the collection and increase the number of tagged genes to at least 9440, approximately two-thirds of all annotated protein-coding genes. We also compare the site specificity of the three major transposons used in the project. All three elements insert only rarely within many Polycomb-regulated regions, a property that may contribute to the origin of "transposon-free regions" (TFRs) in metazoan genomes. Within other genomic regions, Minos transposes essentially at random, whereas P or piggyBac elements display distinctive hotspots and coldspots. P elements, as previously shown, have a strong preference for promoters. In contrast, piggyBac site selectivity suggests that it has evolved to reduce deleterious and increase adaptive changes in host gene expression. The propensity of Minos to integrate broadly makes possible a hybrid finishing strategy for the project that will bring >95% of Drosophila genes under experimental control within their native genomic contexts.


Assuntos
Elementos de DNA Transponíveis , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genes de Insetos , Mutagênese Insercional/métodos , Alelos , Animais , Expressão Gênica , Genoma de Inseto , Modelos Genéticos , Mutação , Fenótipo
19.
Science ; 314(5806): 1747-51, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17138868

RESUMO

We describe a transgenesis platform for Drosophila melanogaster that integrates three recently developed technologies: a conditionally amplifiable bacterial artificial chromosome (BAC), recombineering, and bacteriophage PhiC31-mediated transgenesis. The BAC is maintained at low copy number, facilitating plasmid maintenance and recombineering, but is induced to high copy number for plasmid isolation. Recombineering allows gap repair and mutagenesis in bacteria. Gap repair efficiently retrieves DNA fragments up to 133 kilobases long from P1 or BAC clones. PhiC31-mediated transgenesis integrates these large DNA fragments at specific sites in the genome, allowing the rescue of lethal mutations in the corresponding genes. This transgenesis platform should greatly facilitate structure/function analyses of most Drosophila genes.


Assuntos
Cromossomos Artificiais Bacterianos , Clonagem Molecular/métodos , Elementos de DNA Transponíveis , Drosophila melanogaster/genética , Técnicas de Transferência de Genes , Siphoviridae/genética , Animais , Animais Geneticamente Modificados , Reparo do DNA , Genes de Insetos , Vetores Genéticos , Dados de Sequência Molecular , Mutagênese , Plasmídeos , Recombinação Genética , Transgenes , Transposases/metabolismo
20.
Development ; 133(10): 1979-89, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16624856

RESUMO

The zinc-finger transcription factor Senseless is co-expressed with basic helix-loop-helix (bHLH) proneural proteins in Drosophila sensory organ precursors and is required for their normal development. High levels of Senseless synergize with bHLH proteins and upregulate target gene expression, whereas low levels of Senseless act as a repressor in vivo. However, the molecular mechanism for this dual role is unknown. Here, we show that Senseless binds bHLH proneural proteins via its core zinc fingers and is recruited by proneural proteins to their target enhancers to function as a co-activator. Some point mutations in the Senseless zinc-finger region abolish its DNA-binding ability but partially spare the ability of Senseless to synergize with proneural proteins and to induce sensory organ formation in vivo. Therefore, we propose that the structural basis for the switch between the repressor and co-activator functions of Senseless is the ability of its core zinc fingers to interact physically with both DNA and bHLH proneural proteins. As Senseless zinc fingers are approximately 90% identical to the corresponding zinc fingers of its vertebrate homologue Gfi1, which is thought to cooperate with bHLH proteins in several contexts, the Senseless/bHLH interaction might be evolutionarily conserved.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Drosophila/metabolismo , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sequência Conservada , Drosophila/embriologia , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Embrião não Mamífero , Modelos Biológicos , Dados de Sequência Molecular , Sistema Nervoso/embriologia , Proteínas Nucleares/química , Proteínas Nucleares/genética , Mutação Puntual , Estrutura Terciária de Proteína , Órgãos dos Sentidos/embriologia , Órgãos dos Sentidos/metabolismo , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/química , Fatores de Transcrição/genética , Transgenes
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