Studies of intestinal morphology and cathepsin B expression in a transgenic mouse aiming at intestine-specific expression of Cath B-EGFP

AbstractCathepsin B has been shown to not only reside within endo-lysosomes of intestinal epithelial cells, but it was also secreted into the extracellular space of intestinal mucosa in physiological and pathological conditions. In an effort to further investigate the function of this protease in the intestine, we generated a transgenic mouse model that would enable us to visualize the localization of cathepsin Bin vivo. Previously we showed that the A33-antigen promoter could be successfully usedin vitroin order to express cathepsin B-green fluorescent protein chimeras in cells that co-expressed the intestine-specific transcription factor Cdx1. In this study an analog approach was used to express chi-meric cathepsin B specifically in the intestine of transgenic animals. No overt phenotype was observed for the transgenic mice that reproduced normally. Biochemical and morphological studies confirmed that the overall intestinal phenotype including the structure and polarity of this tissue as well as cell numbers and differentiation states were not altered in the A33-CathB-EGFP mice when compared to wild type animals. However, transgenic expression of chimeric cathepsin B could not be visualized because it was not translatedin situalthough the transgene was maintained over several generations.

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A Tendon-Specific Double Reporter Transgenic Mouse Enables Tracking Cell Lineage and Functions Alteration In Vitro and In Vivo

International Journal of Molecular Sciences ◽

10.3390/ijms222011189 ◽

2021 ◽

Vol 22 (20) ◽

pp. 11189

Author(s):

Rui Chen ◽

Xunlei Zhou ◽

Thomas Skutella

Keyword(s):

Transgenic Mouse ◽

Fluorescent Protein ◽

Cell Lineage ◽

Mouse Line ◽

Reporter System ◽

Specific Expression ◽

Transgenic Mouse Line ◽

Blue Fluorescent Protein

We generated and characterized a transgenic mouse line with the tendon-specific expression of a double fluorescent reporter system, which will fulfill an unmet need for animal models to support real-time monitoring cell behaviors during tendon development, growth, and repair in vitro and in vivo. The mScarlet red fluorescent protein is driven by the Scleraxis (Scx) promoter to report the cell lineage alteration. The blue fluorescent protein reporter is expressed under the control of the 3.6kb Collagen Type I Alpha 1 Chain (Col1a1) proximal promoter. In this promoter, the existence of two promoter regions named tendon-specific cis-acting elements (TSE1, TSE2) ensure the specific expression of blue fluorescent protein (BFP) in tendon tissue. Collagen I is a crucial marker for tendon regeneration that is a major component of healthy tendons. Thus, the alteration of function during tendon repair can be estimated by BFP expression. After mechanical stimulation, the expression of mScarlet and BFP increased in adipose-derived mesenchymal stem cells (ADMSCs) from our transgenic mouse line, and there was a rising trend on tendon key markers. These results suggest that our tendon-specific double reporter system is a novel model used to study cell re-differentiation and extracellular matrix alteration in vitro and in vivo.

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AAV-mediated CRISPR/Cas gene editing of retinal cellsin vivo

10.1101/039156 ◽

2016 ◽

Author(s):

Sandy SC Hung ◽

Vicki Chrysostomou ◽

Fan Li ◽

Jeremiah KH Lim ◽

Jiang-Hui Wang ◽

...

Keyword(s):

Transgenic Mouse ◽

Fluorescent Protein ◽

Yellow Fluorescent Protein ◽

Retinal Function ◽

Gene Modification ◽

Retinal Cells ◽

Adeno Associated Virus ◽

Adult Retina

ABSTRACTPURPOSECRISPR/Cas has recently been adapted to enable efficient editing of the mammalian genome, opening novel avenues for therapeutic intervention of inherited diseases. In seeking to disrupt Yellow Fluorescent Protein (YFP) in a Thy1-YFP transgenic mouse, we assessed the feasibility of utilising the adeno-associated virus 2 (AAV2) to deliver CRISPR/Cas for gene modification of retinal cellsin vivo.METHODSsgRNA plasmids were designed to targetYFPand afterin vitrovalidation, selected guides were cloned into a dual AAV system. One AAV2 construct was used to deliver SpCas9 and the other delivered sgRNA againstYFPorLacZ(control) in the presence of mCherry. Five weeks after intravitreal injection, retinal function was determined using electroretinography and CRISPR/Casmediated gene modifications were quantified in retinal flat mounts.RESULTSAAV2-mediatedin vivodelivery of SpCas9 with sgRNA targetingYFP, significantly reduced the number of YFP fluorescent cells of the inner retina of our transgenic mouse model. Overall, we found an 84.0% (95% CI: 81.8-86.9) reduction of YFP-positive cells inYFP-sgRNA infected retinal cells compared to eyes treated withLacZ-sgRNA. Electroretinography profiling found no significant alteration in retinal function following AAV2-mediated delivery of CRISPR/Cas components compared to contralateral untreated eyes.CONCLUSIONSThy1-YFP transgenic mice were used as a rapid quantifiable means to assess the efficacy of CRISPR/Cas-based retinal gene modificationin vivo. We demonstrate that genomic modification of cells in the adult retina can be readily achieved by viral mediated delivery of CRISPR/Cas.

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In Vivo and In Vitro Tissue-Specific Expression of Green Fluorescent Protein Using the Cre-Lox System in Mouse Embryonic Stem Cells

Stem Cells ◽

10.1634/stemcells.2004-0163 ◽

2005 ◽

Vol 23 (1) ◽

pp. 10-15 ◽

Cited By ~ 7

Author(s):

Jan Schindehütte ◽

Hidefumi Fukumitsu ◽

Patrick Collombat ◽

Gundula Griesel ◽

Christopher Brink ◽

...

Keyword(s):

Stem Cells ◽

Green Fluorescent Protein ◽

Embryonic Stem Cells ◽

Fluorescent Protein ◽

Embryonic Stem ◽

Specific Expression ◽

Tissue Specific Expression ◽

Green Fluorescent

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Designing of a DNA matrix for transgene integration into the bovine beta-lactoglobulin gene locus using CRISPR/Cas9 technology

Ukrainian Journal of Ecology ◽

10.15421/2020_231 ◽

2020 ◽

Vol 10 (5) ◽

pp. 206-210

Author(s):

E.M. Koloskova ◽

V.A. Ezerskiy ◽

K.S. Ostrenko

Keyword(s):

Homologous Recombination ◽

Fluorescent Protein ◽

Transgenic Animals ◽

Biologically Active ◽

Cmv Promoter ◽

Specific Expression ◽

Egfp Gene ◽

Genomic Editing ◽

Beta Lactoglobulin

Beta-lactoglobulin (BLG) is the main protein in milk serum in almost all mammals, with the exception of rodents and primates. Regulatory regions of the beta-lactoglobulin gene in ruminants (sheep, goats, and cattle) as part of genetic constructs provide tissue - specific expression of recombinant protein in the mammary gland and have been actively used in genetic engineering since the beginning of the era of creating transgenic animals. To work effectively with the CRISPR/Cas9 genomic editing method, it is necessary to know the exact DNA sequence of the target gene: this is necessary both for creating a DNA matrix for homologous recombination and for the targeted accuracy of guide RNAs. A polymorphic variant of the bovine BLG gene was identified, whose sperm was used to fertilize cow oocytes in vitro. The aim of this work was to create a plasmid containing 5’ - and 3’ - arms of homology (ha) to the bovine BLG gene. Based on ??TZ57R/T, the pTZhaBLG plasmid was obtained, which has a unique site for EagI restriction at the junction of the homology arms. A fragment containing a biologically active protein gene can be embedded in the resulting plasmid at this restriction site. We created the pBLGcmvEGFP plasmid containing the green fluorescent protein (EGFP) gene under the cytomegalovirus (cmv) promoter: protein expression can serve as a reliable indicator of successful integration of the transgene into the genome. The resulting plasmids in circular or linearized form are intended for site-specific integration by homologous recombination repair into the BLG gene using CRISPR/Cas9 components.

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Distinct roles of apolipoprotein components within the trypanosome lytic factor complex revealed in a novel transgenic mouse model

Journal of Experimental Medicine ◽

10.1084/jem.20071463 ◽

2008 ◽

Vol 205 (8) ◽

pp. 1721-1728 ◽

Cited By ~ 67

Author(s):

Maria Pilar Molina-Portela ◽

Marie Samanovic ◽

Jayne Raper

Keyword(s):

Specific Activity ◽

Transgenic Animals ◽

High Density Lipoproteins ◽

Related Protein ◽

Transgenic Expression ◽

Human Apolipoprotein ◽

Apolipoprotein A ◽

And Function

Humans express a unique subset of high-density lipoproteins (HDLs) called trypanosome lytic factors (TLFs) that kill many Trypanosoma parasite species. The proteins apolipoprotein (apo) A-I, apoL-I, and haptoglobin-related protein, which are involved in TLF structure and function, were expressed through the introduction of transgenes in mice to explore their physiological roles in vivo. Transgenic expression of human apolipoprotein L-I alone conferred trypanolytic activity in vivo. Coexpression of human apolipoprotein A-I and haptoglobin-related protein (Hpr) had an effect on the integration of apolipoprotein L-I into HDL, and both proteins were required to increase the specific activity of TLF, which was measurable in vitro. Unexpectedly, truncated apolipoprotein L-I devoid of the serum resistance gene interacting domain, which was previously shown to kill human infective trypanosomes, was not trypanolytic in transgenic mice despite being coexpressed with human apolipoprotein A-I and Hpr and incorporated into HDLs. We conclude that all three human apolipoproteins act cooperatively to achieve maximal killing capacity and that truncated apolipoprotein L-I does not function in transgenic animals.

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Probing the 14-3-3 Isoform-Specificity Profile of Interactions Stabilized by Fusicoccin A

10.26434/chemrxiv.12052869.v1 ◽

2020 ◽

Author(s):

James Frederich ◽

Ananya Sengupta ◽

Josue Liriano ◽

Ewa A. Bienkiewicz ◽

Brian G. Miller

Keyword(s):

Protein Interactions ◽

Neurological Diseases ◽

Adapter Proteins ◽

Protein Protein Interactions ◽

Specific Expression ◽

Individual Client ◽

Isoform Specificity ◽

Fusicoccin A

Fusicoccin A (FC) is a fungal phytotoxin that stabilizes protein–protein interactions (PPIs) between 14-3-3 adapter proteins and their phosphoprotein interaction partners. In recent years, FC has emerged as an important chemical probe of human 14-3-3 PPIs implicated in cancer and neurological diseases. These previous studies have established the structural requirements for FC-induced stabilization of 14-3-3·client phosphoprotein complexes; however, the effect of different 14-3-3 isoforms on FC activity has not been systematically explored. This is a relevant question for the continued development of FC variants because there are seven distinct isoforms of 14-3-3 in humans. Despite their remarkable sequence and structural similarities, a growing body of experimental evidence supports both tissue-specific expression of 14-3-3 isoforms and isoform-specific functions <i>in vivo</i>. Herein, we report the isoform-specificity profile of FC <i>in vitro</i>using recombinant human 14-3-3 isoforms and a focused library of fluorescein-labeled hexaphosphopeptides mimicking the C-terminal 14-3-3 recognition domains of client phosphoproteins targeted by FC in cell culture. Our results reveal modest isoform preferences for individual client phospholigands and demonstrate that FC differentially stabilizes PPIs involving 14-3-3s. Together, these data provide strong motivation for the development of non-natural FC variants with enhanced selectivity for individual 14-3-3 isoforms.

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Non-Viral Vectors for Gene Delivery

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180110154233 ◽

2018 ◽

Vol 9 (1) ◽

pp. 4-11 ◽

Cited By ~ 5

Author(s):

Aparna Bansal ◽

Himanshu

Keyword(s):

Gene Therapy ◽

Viral Vectors ◽

Transfection Efficiency ◽

Gene Transfection ◽

Expression System ◽

Target Cells ◽

Specific Expression ◽

Naked Dna

Introduction: Gene therapy has emerged out as a promising therapeutic pave for the treatment of genetic and acquired diseases. Gene transfection into target cells using naked DNA is a simple and safe approach which has been further improved by combining vectors or gene carriers. Both viral and non-viral approaches have achieved a milestone to establish this technique, but non-viral approaches have attained a significant attention because of their favourable properties like less immunotoxicity and biosafety, easy to produce with versatile surface modifications, etc. Literature is rich in evidences which revealed that undoubtedly, non–viral vectors have acquired a unique place in gene therapy but still there are number of challenges which are to be overcome to increase their effectiveness and prove them ideal gene vectors. Conclusion: To date, tissue specific expression, long lasting gene expression system, enhanced gene transfection efficiency has been achieved with improvement in delivery methods using non-viral vectors. This review mainly summarizes the various physical and chemical methods for gene transfer in vitro and in vivo.

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Overexpression of the Oral Mucosa-Specific microRNA-31 Promotes Skin Wound Closure

International Journal of Molecular Sciences ◽

10.3390/ijms20153679 ◽

2019 ◽

Vol 20 (15) ◽

pp. 3679 ◽

Cited By ~ 3

Author(s):

Lin Chen ◽

Alyne Simões ◽

Zujian Chen ◽

Yan Zhao ◽

Xinming Wu ◽

...

Keyword(s):

Wound Healing ◽

Oral Mucosa ◽

Wound Closure ◽

Expression Patterns ◽

Skin Wound ◽

Skin Wound Healing ◽

Specific Expression ◽

Keratinocyte Proliferation

Wounds within the oral mucosa are known to heal more rapidly than skin wounds. Recent studies suggest that differences in the microRNAome profiles may underlie the exceptional healing that occurs in oral mucosa. Here, we test whether skin wound-healing can be accelerating by increasing the levels of oral mucosa-specific microRNAs. A panel of 57 differentially expressed high expresser microRNAs were identified based on our previously published miR-seq dataset of paired skin and oral mucosal wound-healing [Sci. Rep. (2019) 9:7160]. These microRNAs were further grouped into 5 clusters based on their expression patterns, and their differential expression was confirmed by TaqMan-based quantification of LCM-captured epithelial cells from the wound edges. Of these 5 clusters, Cluster IV (consisting of 8 microRNAs, including miR-31) is most intriguing due to its tissue-specific expression pattern and temporal changes during wound-healing. The in vitro functional assays show that ectopic transfection of miR-31 consistently enhanced keratinocyte proliferation and migration. In vivo, miR-31 mimic treatment led to a statistically significant acceleration of wound closure. Our results demonstrate that wound-healing can be enhanced in skin through the overexpression of microRNAs that are highly expressed in the privileged healing response of the oral mucosa.

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Development of a Fluorescent Tool for Studying Legionella bozemanae Intracellular Infection

Microorganisms ◽

10.3390/microorganisms9020379 ◽

2021 ◽

Vol 9 (2) ◽

pp. 379

Author(s):

Breanne M. Head ◽

Christopher I. Graham ◽

Teassa MacMartin ◽

Yoav Keynan ◽

Ann Karen C. Brassinga

Keyword(s):

Growth Kinetics ◽

Legionella Pneumophila ◽

Fluorescent Protein ◽

Disease Incidence ◽

Acanthamoeba Castellanii ◽

Infection Model ◽

Intracellular Infection ◽

Green Fluorescent

Legionnaires’ disease incidence is on the rise, with the majority of cases attributed to the intracellular pathogen, Legionella pneumophila. Nominally a parasite of protozoa, L. pneumophila can also infect alveolar macrophages when bacteria-laden aerosols enter the lungs of immunocompromised individuals. L. pneumophila pathogenesis has been well characterized; however, little is known about the >25 different Legionella spp. that can cause disease in humans. Here, we report for the first time a study demonstrating the intracellular infection of an L. bozemanae clinical isolate using approaches previously established for L. pneumophila investigations. Specifically, we report on the modification and use of a green fluorescent protein (GFP)-expressing plasmid as a tool to monitor the L. bozemanae presence in the Acanthamoeba castellanii protozoan infection model. As comparative controls, L. pneumophila strains were also transformed with the GFP-expressing plasmid. In vitro and in vivo growth kinetics of the Legionella parental and GFP-expressing strains were conducted followed by confocal microscopy. Results suggest that the metabolic burden imposed by GFP expression did not impact cell viability, as growth kinetics were similar between the GFP-expressing Legionella spp. and their parental strains. This study demonstrates that the use of a GFP-expressing plasmid can serve as a viable approach for investigating Legionella non-pneumophila spp. in real time.

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A New Transgenic Mouse Line for Imaging Mitochondrial Calcium Signals

Function ◽

10.1093/function/zqab012 ◽

2021 ◽

Vol 2 (3) ◽

Cited By ~ 1

Author(s):

Nelly Redolfi ◽

Elisa Greotti ◽

Giulia Zanetti ◽

Tino Hochepied ◽

Cristina Fasolato ◽

...

Keyword(s):

Transgenic Mouse ◽

Fluorescent Protein ◽

Ex Vivo ◽

Brain Slices ◽

Resonance Energy ◽

Mouse Line ◽

Isolated Cells ◽

Genomic Locus ◽

Transgenic Mouse Line

AbstractMitochondria play a key role in cellular calcium (Ca2+) homeostasis. Dysfunction in the organelle Ca2+ handling appears to be involved in several pathological conditions, ranging from neurodegenerative diseases, cardiac failure and malignant transformation. In the past years, several targeted green fluorescent protein (GFP)-based genetically encoded Ca2+ indicators (GECIs) have been developed to study Ca2+ dynamics inside mitochondria of living cells. Surprisingly, while there is a number of transgenic mice expressing different types of cytosolic GECIs, few examples are available expressing mitochondria-localized GECIs, and none of them exhibits adequate spatial resolution. Here we report the generation and characterization of a transgenic mouse line (hereafter called mt-Cam) for the controlled expression of a mitochondria-targeted, Förster resonance energy transfer (FRET)-based Cameleon, 4mtD3cpv. To achieve this goal, we engineered the mouse ROSA26 genomic locus by inserting the optimized sequence of 4mtD3cpv, preceded by a loxP-STOP-loxP sequence. The probe can be readily expressed in a tissue-specific manner upon Cre recombinase-mediated excision, obtainable with a single cross. Upon ubiquitous Cre expression, the Cameleon is specifically localized in the mitochondrial matrix of cells in all the organs and tissues analyzed, from embryos to aged animals. Ca2+ imaging experiments performed in vitro and ex vivo in brain slices confirmed the functionality of the probe in isolated cells and live tissues. This new transgenic mouse line allows the study of mitochondrial Ca2+ dynamics in different tissues with no invasive intervention (such as viral infection or electroporation), potentially allowing simple calibration of the fluorescent signals in terms of mitochondrial Ca2+ concentration ([Ca2+]).

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