351 research outputs found

    Lentiviral Mediated Transgenesis by In Vivo Manipulation of Spermatogonial Stem Cells

    Get PDF
    This report describes a technique for the generation of transgenic mice by in vivo manipulation of spermatogonial stem cells with a high rate of success. Spermatogonial stem cells (SSCs) in pre-pubescent animals were infected in vivo with recombinant lentiviruses expressing EGFP-f and mated with normal females. All male pre-founder mice produced transgenic pups with an overall success rate of over 60%. The transgene was heritable and the pre-founder mice could be used in multiple mating experiments. This technology could be used to perform overexpression/knockdown screens in vivo using bar-coded lentiviruses, thus permitting the design of genetic screens in the mouse. Further, this technology could be adapted to other laboratory animals resulting in the generation of model systems that closely approximate human development and disease

    How digital is agriculture in a subset of countries from South America? Adoption and limitations

    Get PDF
    Digital agriculture (DA) can contribute solutions to meet an increase in healthy, nutritious, and affordable food demands in an efficient and sustainable way. South America (SA) is one of the main grain and protein producers in the world but the status of DA in the region is unknown. A systematic review and case studies from Brazil, Argentina, Uruguay, and Chile were conducted to address the following objectives: (1) quantify adoption of existing DA technologies, (2) identify limitations for DA adoption; and (3) summarise existing metrics to benchmark DA benefits. Level of DA adoption was led by Brazil and Argentina followed by Uruguay and at a slower rate, Chile. GPS guidance systems, mapping tools, mobile apps and remote sensing were the most adopted DA technologies in SA. The most reported limitations to adoption were technology cost, lack of training, limited number of companies providing services, and unclear benefits from DA. Across the case studies, there was no clear definition of DA. To mitigate some of these limitations, our findings suggest the need for a DA educational curriculum that can fulfill the demand for job skills such as data processing, analysis and interpretation. Regional efforts are needed to standardise these metrics. This will allow stakeholders to design targeted initiatives to promote DA towards sustainability of food production in the region

    Efficient generation of transgenic pigs using equine infectious anaemia virus (EIAV) derived vector

    Get PDF
    AbstractTraditional methods of transgene delivery in livestock are inefficient. Recently, human immunodeficiency virus (HIV-1) based lentiviral vectors have been shown to offer an efficient transgene delivery system. We now extend this method by demonstrating efficient generation of transgenic pigs using an equine infectious anaemia virus derived vector. We used this vector to deliver a green fluorescent protein expressing transgene; 31% of injected/transferred eggs resulted in a transgenic founder animal and 95% of founder animals displayed green fluorescence. This compares favourably with results using HIV-1 based vectors, and is substantially more efficient than the standard pronuclear microinjection method, indicating that lentiviral transgene delivery may be a general tool with which to efficiently generate transgenic mammals

    Coenzyme Q10 partially restores pathological alterations in a macrophage model of Gaucher disease

    Get PDF
    Background Gaucher disease (GD) is caused by mutations in the GBA1 gene which encodes lysosomal β-glucocerebrosidase (GCase). In GD, partial or complete loss of GCase activity causes the accumulation of the glycolipids glucosylceramide (GlcCer) and glucosylsphingosine in the lysosomes of macrophages. In this manuscript, we investigated the effects of glycolipids accumulation on lysosomal and mitochondrial function, inflammasome activation and efferocytosis capacity in a THP-1 macrophage model of Gaucher disease. In addition, the beneficial effects of coenzyme Q10 (CoQ) supplementation on cellular alterations were evaluated. Chemically-induced Gaucher macrophages were developed by differentiateing THP-1 monocytes to macrophages by treatment with phorbol 12-myristate 13-acetate (PMA) and then inhibiting intracellular GCase with conduritol B-epoxide (CBE), a specific irreversible inhibitor of GCase activity, and supplementing the medium with exogenous GlcCer. This cell model accumulated up to 16-fold more GlcCer compared with control THP-1 cells. Results Chemically-induced Gaucher macrophages showed impaired autophagy flux associated with mitochondrial dysfunction and increased oxidative stress, inflammasome activation and impaired efferocytosis. All abnormalities were partially restored by supplementation with CoQ. Conclusion These data suggest that targeting mitochondria function and oxidative stress by CoQ can ameliorate the pathological phenotype of Gaucher cells. Chemically-induced Gaucher macrophages provide cellular models that can be used to investigate disease pathogenesis and explore new therapeutics for GD.info:eu-repo/semantics/publishedVersio

    Quantitative assessment on the cloning efficiencies of lentiviral transfer vectors with a unique clone site

    Get PDF
    Lentiviral vectors (LVs) are powerful tools for transgene expression in vivo and in vitro. However, the construction of LVs is of low efficiency, due to the large sizes and lack of proper clone sites. Therefore, it is critical to develop efficient strategies for cloning LVs. Here, we reported a combinatorial strategy to efficiently construct LVs using EGFP, hPlk2 wild type (WT) and mutant genes as inserts. Firstly, site-directed mutagenesis (SDM) was performed to create BamH I site for the inserts; secondly, pWPI LV was dephosphorylated after BamH I digestion; finally, the amounts and ratios of the insert and vector DNA were optimized to increase monomeric ligation. Our results showed that the total percentage of positive clones was approximately 48%±7.6%. Using this method, almost all the vectors could be constructed through two or three minipreps. Therefore, our study provided an efficient method for constructing large-size vectors

    Impaired Sprouting and Axonal Atrophy in Cerebellar Climbing Fibres following In Vivo Silencing of the Growth-Associated Protein GAP-43

    Get PDF
    The adult mammalian central nervous system has a limited ability to establish new connections and to recover from traumatic or degenerative events. The olivo-cerebellar network represents an excellent model to investigate neuroprotection and repair in the brain during adulthood, due to its high plasticity and ordered synaptic organization. To shed light on the molecular mechanisms involved in these events, we focused on the growth-associated protein GAP-43 (also known as B-50 or neuromodulin). During development, this protein plays a crucial role in growth and in branch formation of neurites, while in the adult it is only expressed in a few brain regions, including the inferior olive (IO) where climbing fibres (CFs) originate. Following axotomy GAP-43 is usually up-regulated in association with regeneration. Here we describe an in vivo lentiviral-mediated gene silencing approach, used for the first time in the olivo-cerebellar system, to efficiently and specifically downregulate GAP-43 in rodents CFs. We show that lack of GAP-43 causes an atrophy of the CF in non-traumatic conditions, consisting in a decrease of its length, branching and number of synaptic boutons. We also investigated CF regenerative ability by inducing a subtotal lesion of the IO. Noteworthy, surviving CFs lacking GAP-43 were largely unable to sprout on surrounding Purkinje cells. Collectively, our results demonstrate that GAP-43 is essential both to maintain CFs structure in non-traumatic condition and to promote sprouting after partial lesion of the IO

    How digital is agriculture in a subset of countries from South America? Adoption and limitations.

    Get PDF
    Abstract. Digital agriculture (DA) can contribute solutions to meet an increase in healthy, nutritious, and affordable food demands in an efficient and sustainable way. South America (SA) is one of the main grain and protein producers in the world but the status of DA in the region is unknown. A systematic review and case studies from Brazil, Argentina, Uruguay, and Chile were conducted to address the following objectives: (1) quantify adoption of existing DA technologies, (2) identify limitations for DA adoption; and (3) summarise existing metrics to benchmark DA benefits. Level of DA adoption was led by Brazil and Argentina followed by Uruguay and at a slower rate, Chile. GPS guidance systems, mapping tools, mobile apps and remote sensing were the most adopted DA technologies in SA. The most reported limitations to adoption were technology cost, lack of training, limited number of companies providing services, and unclear benefits from DA. Across the case studies, there was no clear definition of DA. To mitigate some of these limitations, our findings suggest the need for a DA educational curriculum that can fulfill the demand for job skills such as data processing, analysis and interpretation. Regional efforts are needed to standardise these metrics. This will allow stakeholders to design targeted initiatives to promote DA towards sustainability of food production in the region.Special issue

    Cloning and characterization of a novel alternatively spliced transcript of the human CHD7 putative helicase

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The <it>CHD7 </it>(Chromodomain Helicase DNA binding protein 7) gene encodes a member of the chromodomain family of ATP-dependent chromatin remodeling enzymes. Mutations in the <it>CHD7 </it>gene are found in individuals with CHARGE, a syndrome characterized by multiple birth malformations in several tissues. CHD7 was identified as a binding partner of PBAF complex (Polybromo and BRG Associated Factor containing complex) playing a central role in the transcriptional reprogramming process associated to the formation of multipotent migratory neural crest, a transient cell population associated with the genesis of various tissues. <it>CHD7 </it>is a large gene containing 38 annotated exons and spanning 200 kb of genomic sequence. Although genes containing such number of exons are expected to have several alternative transcripts, there are very few evidences of alternative transcripts associated to <it>CHD7 </it>to date indicating that alternative splicing associated to this gene is poorly characterized.</p> <p>Findings</p> <p>Here, we report the cloning and characterization by experimental and computational studies of a novel alternative transcript of the human <it>CHD7 </it>(named CHD7 CRA_e), which lacks most of its coding exons. We confirmed by overexpression of CHD7 CRA_e alternative transcript that it is translated into a protein isoform lacking most of the domains displayed by the canonical isoform. Expression of the CHD7 CRA_e transcript was detected in normal liver, in addition to the DU145 human prostate carcinoma cell line from which it was originally isolated.</p> <p>Conclusions</p> <p>Our findings indicate that the splicing event associated to the CHD7 CRA_e alternative transcript is functional. The characterization of the CHD7 CRA_e novel isoform presented here not only sets the basis for more detailed functional studies of this isoform, but, also, contributes to the alternative splicing annotation of the <it>CHD7 </it>gene and the design of future functional studies aimed at the elucidation of the molecular functions of its gene products.</p

    Interaction of the Transcription Start Site Core Region and Transcription Factor YY1 Determine Ascorbate Transporter SVCT2 Exon 1a Promoter Activity

    Get PDF
    Transcription of the ascorbate transporter, SVCT2, is driven by two distinct promoters in exon 1 of the transporter sequence. The exon 1a promoter lacks a classical transcription start site and little is known about regulation of promoter activity in the transcription start site core (TSSC) region. Here we present evidence that the TSSC binds the multifunctional initiator-binding protein YY1. Electrophoresis shift assays using YY1 antibody showed that YY1 is present as one of two major complexes that specifically bind to the TSSC. The other complex contains the transcription factor NF-Y. Mutations in the TSSC that decreased YY1 binding also impaired the exon 1a promoter activity despite the presence of an upstream activating NF-Y/USF complex, suggesting that YY1 is involved in the regulation of the exon 1a transcription. Furthermore, YY1 interaction with NF-Y and/or USF synergistically enhanced the exon 1a promoter activity in transient transfections and co-activator p300 enhanced their synergistic activation. We propose that the TSSC plays a vital role in the exon 1a transcription and that this function is partially carried out by the transcription factor YY1. Moreover, co-activator p300 might be able to synergistically enhance the TSSC function via a “bridge” mechanism with upstream sequences

    Berberine Chloride Mediates Its Anti-Leishmanial Activity via Differential Regulation of the Mitogen Activated Protein Kinase Pathway in Macrophages

    Get PDF
    BACKGROUND: A complex interplay between Leishmania and macrophages influences parasite survival and necessitates disruption of signaling molecules, eventually resulting in impairment of macrophage function. In this study, we demonstrate the immunomodulatory activity of Berberine chloride in Leishmania infected macrophages. PRINCIPAL FINDINGS: The IC(50) of Berberine chloride, a quaternary isoquinoline alkaloid was tested in an amastigote macrophage model and its safety index measured by a cell viability assay. It eliminated intracellular amastigotes, the IC(50) being 2.8 fold lower than its IC(50) in promastigotes (7.10 µM vs. 2.54 µM) and showed a safety index >16. Levels of intracellular and extracellular nitric oxide (NO) as measured by flow cytometry and Griess assay respectively showed that Berberine chloride in Leishmania infected macrophages increased production of NO. Measurement of the mRNA expression of iNOS, IL-12 and IL-10 by RT-PCR along with levels of IL-12p40 and IL-10 by ELISA showed that in infected macrophages, Berberine chloride enhanced expression of iNOS and IL-12p40, concomitant with a downregulation of IL-10. The phosphorylation status of extracellular signal related kinase (ERK1/2) and p38 mitogen activated protein kinase (p38 MAPK) was studied by western blotting. In infected macrophages, Berberine chloride caused a time dependent activation of p38 MAPK along with deactivation of ERK1/2; addition of a p38 MAPK inhibitor SB203580 inhibited the increased generation of NO and IL-12p40 by Berberine chloride as also prevented its decrease of IL-10. CONCLUSIONS: Berberine chloride modulated macrophage effector responses via the mitogen activated protein kinase (MAPK) pathway, highlighting the importance of MAPKs as an antiparasite target
    corecore