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1.
Planta ; 260(1): 18, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38837044

ABSTRACT

MAIN CONCLUSION: We have developed and optimized a rapid, versatile Agrobacterium-mediated transient expression system for cannabis seedlings that can be used in functional genomics studies of both hemp-type and drug-type cannabis. Cannabis (Cannabis sativa L.) holds great promise in the medical and food industries due to its diverse chemical composition, including specialized cannabinoids. However, the study of key genes involved in various biological processes, including secondary metabolite biosynthesis, has been hampered by the lack of efficient in vivo functional analysis methods. Here, we present a novel, short-cycle, high-efficiency transformation method for cannabis seedlings using Agrobacterium tumefaciens. We used the RUBY reporter system to monitor transformation results without the need for chemical treatments or specialized equipment. Four strains of A. tumefaciens (GV3101, EHA105, LBA4404, and AGL1) were evaluated for transformation efficiency, with LBA4404 and AGL1 showing superior performance. The versatility of the system was further demonstrated by successful transformation with GFP and GUS reporter genes. In addition, syringe infiltration was explored as an alternative to vacuum infiltration, offering simplicity and efficiency for high-throughput applications. Our method allows rapid and efficient in vivo transformation of cannabis seedlings, facilitating large-scale protein expression and high-throughput characterization studies.


Subject(s)
Agrobacterium tumefaciens , Cannabis , Genomics , Seedlings , Transformation, Genetic , Agrobacterium tumefaciens/genetics , Seedlings/genetics , Genomics/methods , Cannabis/genetics , Cannabis/metabolism , Plants, Genetically Modified , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism
2.
Methods Mol Biol ; 2807: 299-323, 2024.
Article in English | MEDLINE | ID: mdl-38743237

ABSTRACT

Ex vivo cervical tissue explant models offer a physiologically relevant approach for studying virus-host interactions that underlie mucosal HIV-1 transmission to women. However, the utility of cervical explant tissue (CET) models has been limited for both practical and technical reasons. These include assay variation, inadequate sensitivity for assessing HIV-1 infection and replication in tissue, and constraints imposed by the requirement for using multiple replica samples of CET to test each experimental variable and assay parameter. Here, we describe an experimental approach that employs secreted nanoluciferase (sNLuc) and current HIV-1 reporter virus technologies to overcome certain limitations of earlier ex vivo CET models. This method augments application of the CET model for investigating important questions involving mucosal HIV-1 transmission.


Subject(s)
Cervix Uteri , HIV Infections , HIV-1 , HIV-1/physiology , HIV-1/genetics , Humans , Cervix Uteri/virology , Cervix Uteri/metabolism , Female , HIV Infections/virology , Luciferases/genetics , Luciferases/metabolism , Genes, Reporter , Mucous Membrane/virology , Mucous Membrane/metabolism , Virus Replication
3.
Methods Mol Biol ; 2808: 1-7, 2024.
Article in English | MEDLINE | ID: mdl-38743358

ABSTRACT

We have adopted a real-time assay based on a dual-split reporter to assess cell-cell fusion mediated by the measles virus (MeV) membrane fusion machinery. This reporter system is comprised of two expression vectors, each encoding a segment of Renilla luciferase fused to a segment of GFP. To regain function, the two segments need to associate, which is dependent on cell-cell fusion between effector cells expressing the MeV fusion machinery and target cells expressing the corresponding MeV receptor. By measuring reconstituted luciferase activity, we can follow the kinetics of cell-cell fusion and quantify the extent of fusion. This assay lends itself to the study of the MeV fusion machinery comprised of the attachment and fusion glycoproteins, the matrix protein, and the MeV receptors. Moreover, entry inhibitors targeting attachment or fusion can be readily screened using this assay. Finally, this assay can be easily adopted to study the entry of other members of the Paramyxoviridae, as we have demonstrated for the henipaviruses.


Subject(s)
Cell Fusion , Measles virus , Virus Internalization , Measles virus/genetics , Measles virus/physiology , Humans , Animals , Cell Fusion/methods , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Chlorocebus aethiops , Cell Line , Vero Cells , Luciferases, Renilla/genetics , Luciferases, Renilla/metabolism
4.
Protein Eng Des Sel ; 372024 Jan 29.
Article in English | MEDLINE | ID: mdl-38696722

ABSTRACT

The yeast endoplasmic reticulum sequestration and screening (YESS) system is a broadly applicable platform to perform high-throughput biochemical studies of post-translational modification enzymes (PTM-enzymes). This system enables researchers to profile and engineer the activity and substrate specificity of PTM-enzymes and to discover inhibitor-resistant enzyme mutants. In this study, we expand the capabilities of YESS by transferring its functional components to integrative plasmids. The YESS integrative system yields uniform protein expression and protease activities in various configurations, allows one to integrate activity reporters at two independent loci and to split the system between integrative and centromeric plasmids. We characterize these integrative reporters with two viral proteases, Tobacco etch virus (TEVp) and 3-chymotrypsin like protease (3CLpro), in terms of coefficient of variance, signal-to-noise ratio and fold-activation. Overall, we provide a framework for chromosomal-based studies that is modular, enabling rigorous high-throughput assays of PTM-enzymes in yeast.


Subject(s)
Endoplasmic Reticulum , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/genetics , Protein Processing, Post-Translational , Genes, Reporter , Endopeptidases/genetics , Endopeptidases/metabolism , Plasmids/genetics , Plasmids/metabolism
5.
Cells ; 13(9)2024 May 06.
Article in English | MEDLINE | ID: mdl-38727323

ABSTRACT

IL-36 cytokines are emerging as beneficial in immunity against pathogens and cancers but can also be detrimental when dysregulated in autoimmune and autoinflammatory conditions. Interest in targeting IL-36 activity for therapeutic purposes is rapidly growing, yet many unknowns about the functions of these cytokines remain. Thus, the availability of robust research tools is essential for both fundamental basic science and pre-clinical studies to fully access outcomes of any manipulation of the system. For this purpose, a floxed Il1rl2, the gene encoding the IL-36 receptor, mouse strain was developed to facilitate the generation of conditional knockout mice. The targeted locus was engineered to contain an inverted mCherry reporter sequence that upon Cre-mediated recombination will be flipped and expressed under the control of the endogenous Il1rl2 promoter. This feature can be used to confirm knockout in individual cells but also as a reporter to determine which cells express the IL-36 receptor IL-1RL2. The locus was confirmed to function as intended and further used to demonstrate the expression of IL-1RL2 in barrier tissues. Il1rl2 expression was detected in leukocytes in all barrier tissues. Interestingly, strong expression was observed in epithelial cells at locations in direct contact with the environment such as the skin, oral mucosa, the esophagus, and the upper airways, but almost absent from epithelial cells at more inward facing sites, including lung alveoli, the small intestine, and the colon. These findings suggest specialized functions of IL-1RL2 in outward facing epithelial tissues and cells. The generated mouse model should prove valuable in defining such functions and may also facilitate basic and translational research.


Subject(s)
Mice, Knockout , Animals , Mice , Genes, Reporter , Genetic Loci , Mice, Inbred C57BL , Receptors, Interleukin-1/metabolism , Receptors, Interleukin-1/genetics , Interleukin-1 Receptor-Like 1 Protein/metabolism , Interleukin-1 Receptor-Like 1 Protein/genetics , Gene Expression Regulation
6.
Cells ; 13(10)2024 May 10.
Article in English | MEDLINE | ID: mdl-38786041

ABSTRACT

Monocytes, as well as downstream macrophages and dendritic cells, are essential players in the immune system, fulfilling key roles in homeostasis as well as in inflammatory conditions. Conventionally, driven by studies on reporter models, mouse monocytes are categorized into a classical and a non-classical subset based on their inversely correlated surface expression of Ly6C/CCR2 and CX3CR1. Here, we aimed to challenge this concept by antibody staining and reporter mouse models. Therefore, we took advantage of Cx3cr1GFP and Ccr2RFP reporter mice, in which the respective gene was replaced by a fluorescent reporter protein gene. We analyzed the expression of CX3CR1 and CCR2 by flow cytometry using several validated fluorochrome-coupled antibodies and compared them with the reporter gene signal in these reporter mouse strains. Although we were able to validate the specificity of the fluorochrome-coupled flow cytometry antibodies, mouse Ly6Chigh classical and Ly6Clow non-classical monocytes showed no differences in CX3CR1 expression levels in the peripheral blood and spleen when stained with these antibodies. On the contrary, in Cx3cr1GFP reporter mice, we were able to reproduce the inverse correlation of the CX3CR1 reporter gene signal and Ly6C surface expression. Furthermore, differential CCR2 surface expression correlating with the expression of Ly6C was observed by antibody staining, but not in Ccr2RFP reporter mice. In conclusion, our data suggest that phenotyping strategies for mouse monocyte subsets should be carefully selected. In accordance with the literature, the suitability of CX3CR1 antibody staining is limited, whereas for CCR2, caution should be applied when using reporter mice.


Subject(s)
CX3C Chemokine Receptor 1 , Flow Cytometry , Monocytes , Receptors, CCR2 , Animals , Receptors, CCR2/metabolism , Receptors, CCR2/genetics , Monocytes/metabolism , CX3C Chemokine Receptor 1/metabolism , CX3C Chemokine Receptor 1/genetics , Mice , Antibodies/immunology , Genes, Reporter , Phenotype , Mice, Inbred C57BL , Mice, Transgenic , Green Fluorescent Proteins/metabolism , Antigens, Ly/metabolism , Antigens, Ly/genetics
7.
Bull Exp Biol Med ; 176(5): 595-598, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38724816

ABSTRACT

A large-scale search for the genetic variants with a bias in the representation of alleles in transcriptome data (AE SNPs) and the binding sites in microRNA 3'-UTRs was performed and their functional significance was assessed using massively parallel reporter assay (MPRA). Of the 629,559 associated "SNP-gene" pairs (eQTLs) discovered in the human liver tissue according to the GTEx Analysis V8 data, 4394 polymorphic positions in the 3'-UTRs of the genes, which represent the eQTLs for these genes were selected. The TargetScanHuman 7.0 algorithm and PolymiRTS database were searched for the potential microRNA-binding sites. Of the predicted microRNA sites affected by eQTL-SNPs, we selected 51 sites with the best evidence of functionality according to Ago2-CLIP-seq, CLEAR-CLIP, and eCLIP-seq for RNA-binding proteins. For MPRA, a library of the plasmids carrying the main and alternative alleles for each AE SNP (in total, 102 constructs) was created. Allele-specific expression for 6 SNPs was detected by transfection of the HepG2 cell line with the constructed plasmid library and sequencing of target DNA and RNA sequences using the Illumina (MiSeq) platform.


Subject(s)
3' Untranslated Regions , Alleles , MicroRNAs , Polymorphism, Single Nucleotide , Humans , Polymorphism, Single Nucleotide/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Hep G2 Cells , Binding Sites/genetics , 3' Untranslated Regions/genetics , High-Throughput Nucleotide Sequencing/methods , Genes, Reporter/genetics , Liver/metabolism , Argonaute Proteins/genetics , Argonaute Proteins/metabolism , Transcriptome/genetics
8.
Genome Biol ; 25(1): 137, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38790076

ABSTRACT

BACKGROUND: Individual cells from isogenic populations often display large cell-to-cell differences in gene expression. This "noise" in expression derives from several sources, including the genomic and cellular environment in which a gene resides. Large-scale maps of genomic environments have revealed the effects of epigenetic modifications and transcription factor occupancy on mean expression levels, but leveraging such maps to explain expression noise will require new methods to assay how expression noise changes at locations across the genome. RESULTS: To address this gap, we present Single-cell Analysis of Reporter Gene Expression Noise and Transcriptome (SARGENT), a method that simultaneously measures the noisiness of reporter genes integrated throughout the genome and the global mRNA profiles of individual reporter-gene-containing cells. Using SARGENT, we perform the first comprehensive genome-wide survey of how genomic locations impact gene expression noise. We find that the mean and noise of expression correlate with different histone modifications. We quantify the intrinsic and extrinsic components of reporter gene noise and, using the associated mRNA profiles, assign the extrinsic component to differences between the CD24+ "stem-like" substate and the more "differentiated" substate. SARGENT also reveals the effects of transgene integrations on endogenous gene expression, which will help guide the search for "safe-harbor" loci. CONCLUSIONS: Taken together, we show that SARGENT is a powerful tool to measure both the mean and noise of gene expression at locations across the genome and that the data generatd by SARGENT reveals important insights into the regulation of gene expression noise genome-wide.


Subject(s)
Single-Cell Analysis , Humans , Genes, Reporter , Transcriptome , Genomics/methods
9.
Int J Mol Sci ; 25(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38791162

ABSTRACT

Early detection of drug-induced kidney injury is essential for drug development. In this study, multiple low-dose aristolochic acid (AA) and cisplatin (Cis) injections increased renal mRNA levels of inflammation, fibrosis, and renal tubule injury markers. We applied a serum amyloid A3 (Saa3) promoter-driven luciferase reporter (Saa3 promoter-luc mice) to these two tubulointerstitial nephritis models and performed in vivo bioluminescence imaging to monitor early renal pathologies. The bioluminescent signals from renal tissues with AA or CIS injections were stronger than those from normal kidney tissues obtained from normal mice. To verify whether the visualized bioluminescence signal was specifically generated by the injured kidney, we performed in vivo bioluminescence analysis after opening the stomachs of Saa3 promoter-luc mice, and the Saa3-mediated bioluminescent signal was specifically detected in the injured kidney. This study showed that Saa3 promoter activity is a potent non-invasive indicator for the early detection of drug-induced nephrotoxicity.


Subject(s)
Aristolochic Acids , Luciferases , Promoter Regions, Genetic , Serum Amyloid A Protein , Animals , Serum Amyloid A Protein/genetics , Serum Amyloid A Protein/metabolism , Mice , Luciferases/metabolism , Luciferases/genetics , Aristolochic Acids/toxicity , Genes, Reporter , Cisplatin/toxicity , Cisplatin/adverse effects , Luminescent Measurements/methods , Male , Kidney Diseases/chemically induced , Kidney Diseases/genetics , Kidney Diseases/metabolism , Kidney Diseases/pathology , Kidney/metabolism , Kidney/drug effects , Kidney/pathology , Disease Models, Animal , Mice, Inbred C57BL
10.
Viruses ; 16(5)2024 04 29.
Article in English | MEDLINE | ID: mdl-38793589

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces direct cytopathic effects, complicating the establishment of low-cytotoxicity cell culture models for studying its replication. We initially developed a DNA vector-based replicon system utilizing the CMV promoter to generate a recombinant viral genome bearing reporter genes. However, this system frequently resulted in drug resistance and cytotoxicity, impeding model establishment. Herein, we present a novel cell culture model with SARS-CoV-2 replication induced by Cre/LoxP-mediated DNA recombination. An engineered SARS-CoV-2 transcription unit was subcloned into a bacterial artificial chromosome (BAC) vector. To enhance biosafety, the viral spike protein gene was deleted, and the nucleocapsid gene was replaced with a reporter gene. An exogenous sequence was inserted within NSP1 as a modulatory cassette that is removable after Cre/LoxP-mediated DNA recombination and subsequent RNA splicing. Using the PiggyBac transposon strategy, the transcription unit was integrated into host cell chromatin, yielding a stable cell line capable of inducing recombinant SARS-CoV-2 RNA replication. The model exhibited sensitivity to the potential antivirals forsythoside A and verteporfin. An innovative inducible SARS-CoV-2 replicon cell model was introduced to further explore the replication and pathogenesis of the virus and facilitate screening and assessment of anti-SARS-CoV-2 therapeutics.


Subject(s)
SARS-CoV-2 , Virus Replication , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Humans , COVID-19/virology , Cell Culture Techniques , Replicon/genetics , Animals , Genome, Viral , Cell Line , Chromosomes, Artificial, Bacterial/genetics , Chlorocebus aethiops , Vero Cells , RNA, Viral/genetics , RNA, Viral/metabolism , Genes, Reporter , Recombination, Genetic
11.
J Pharm Biomed Anal ; 245: 116185, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38723556

ABSTRACT

Human epidermal growth factor receptor 2 (HER2) is a key player in the pathogenesis and progression of breast cancer and is currently a primary target for breast cancer immunotherapy. Bioactivity determination is necessary to guarantee the safety and efficacy of therapeutic antibodies targeting HER2. Nevertheless, currently available bioassays for measuring the bioactivity of anti-HER2 mAbs are either not representative or have high variability. Here, we established a reliable reporter gene assay (RGA) based on T47D-SRE-Luc cell line that expresses endogenous HER2 and luciferase controlled by serum response element (SRE) to measure the bioactivity of anti-HER2 antibodies. Neuregulin-1 (NRG-1) can lead to the heterodimerization of HER2 on the cell membrane and induce the expression of downstream SRE-controlled luciferase, while pertuzumab can dose-dependently reverse the reaction, resulting in a good dose-response curve reflecting the activity of the antibody. After optimizing the relevant assay parameters, the established RGA was fully validated based on ICH-Q2 (R1), which demonstrated that the method had excellent specificity, accuracy, precision, linearity, and stability. In summary, this robust and innovative bioactivity determination assay can be applied in the development and screening, release control, biosimilar assessment and stability studies of anti-HER2 mAbs.


Subject(s)
Antibodies, Monoclonal, Humanized , Biological Assay , Genes, Reporter , Luciferases , Neuregulin-1 , Receptor, ErbB-2 , Receptor, ErbB-2/genetics , Receptor, ErbB-2/immunology , Receptor, ErbB-2/antagonists & inhibitors , Humans , Cell Line, Tumor , Antibodies, Monoclonal, Humanized/pharmacology , Biological Assay/methods , Luciferases/genetics , Neuregulin-1/genetics , Breast Neoplasms/drug therapy , Breast Neoplasms/immunology , Breast Neoplasms/genetics , Female , Antineoplastic Agents, Immunological/pharmacology , Reproducibility of Results , Response Elements
12.
Dev Biol ; 512: 35-43, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38710381

ABSTRACT

The larval stage of the Drosophila melanogaster life cycle is characterized by rapid growth and nutrient storage that occur over three instar stages separated by molts. In the third instar, the steroid hormone ecdysone drives key developmental processes and behaviors that occur in a temporally-controlled sequence and prepare the animal to undergo metamorphosis. Accurately staging Drosophila larvae within the final third instar is critical due to the rapid developmental progress at this stage, but it is challenging because the rate of development varies widely across a population of animals even if eggs are laid within a short period of time. Moreover, many methods to stage third instar larvae are cumbersome, and inherent variability in the rate of development confounds some of these approaches. Here we demonstrate the usefulness of the Sgs3-GFP transgene, a fusion of the Salivary gland secretion 3 (Sgs3) and GFP proteins, for staging third instar larvae. Sgs3-GFP is expressed in the salivary glands in an ecdysone-dependent manner from the midpoint of the third instar, and its expression pattern changes reproducibly as larvae progress through the third instar. We show that Sgs3-GFP can easily be incorporated into experiments, that it allows collection of developmentally-equivalent individuals from a mixed population of larvae, and that its use enables precise assessment of changing levels of hormones, metabolites, and gene expression during the second half of the third instar.


Subject(s)
Drosophila melanogaster , Ecdysone , Green Fluorescent Proteins , Larva , Phenotype , Salivary Glands , Animals , Larva/metabolism , Larva/genetics , Salivary Glands/metabolism , Green Fluorescent Proteins/metabolism , Green Fluorescent Proteins/genetics , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Ecdysone/metabolism , Drosophila Proteins/metabolism , Drosophila Proteins/genetics , Genes, Reporter , Gene Expression Regulation, Developmental/genetics , Animals, Genetically Modified , Metamorphosis, Biological/genetics
13.
Sci Rep ; 14(1): 10078, 2024 05 02.
Article in English | MEDLINE | ID: mdl-38698030

ABSTRACT

Comparative analyses between traditional model organisms, such as the fruit fly Drosophila melanogaster, and more recent model organisms, such as the red flour beetle Tribolium castaneum, have provided a wealth of insight into conserved and diverged aspects of gene regulation. While the study of trans-regulatory components is relatively straightforward, the study of cis-regulatory elements (CREs, or enhancers) remains challenging outside of Drosophila. A central component of this challenge has been finding a core promoter suitable for enhancer-reporter assays in diverse insect species. Previously, we demonstrated that a Drosophila Synthetic Core Promoter (DSCP) functions in a cross-species manner in Drosophila and Tribolium. Given the over 300 million years of divergence between the Diptera and Coleoptera, we reasoned that DSCP-based reporter constructs will be useful when studying cis-regulation in a variety of insect models across the holometabola and possibly beyond. To this end, we sought to create a suite of new DSCP-based reporter vectors, leveraging dual compatibility with piggyBac and PhiC31-integration, the 3xP3 universal eye marker, GATEWAY cloning, different colors of reporters and markers, as well as Gal4-UAS binary expression. While all constructs functioned properly with a Tc-nub enhancer in Drosophila, complications arose with tissue-specific Gal4-UAS binary expression in Tribolium. Nevertheless, the functionality of these constructs across multiple holometabolous orders suggests a high potential compatibility with a variety of other insects. In addition, we present the piggyLANDR (piggyBac-LoxP AttP Neutralizable Destination Reporter) platform for the establishment of proper PhiC31 landing sites free from position effects. As a proof-of-principle, we demonstrated the workflow for piggyLANDR in Drosophila. The potential utility of these tools ranges from molecular biology research to pest and disease-vector management, and will help advance the study of gene regulation beyond traditional insect models.


Subject(s)
Drosophila melanogaster , Genes, Reporter , Genetic Vectors , Promoter Regions, Genetic , Tribolium , Animals , Genetic Vectors/genetics , Tribolium/genetics , Drosophila melanogaster/genetics , Enhancer Elements, Genetic , Regulatory Sequences, Nucleic Acid/genetics , Insecta/genetics , Animals, Genetically Modified
14.
Sci Rep ; 14(1): 12555, 2024 05 31.
Article in English | MEDLINE | ID: mdl-38821978

ABSTRACT

Fluorescent detection in cells has been tremendously developed over the years and now benefits from a large array of reporters that can provide sensitive and specific detection in real time. However, the intracellular monitoring of metabolite levels still poses great challenges due to the often complex nature of detected metabolites. Here, we provide a systematic analysis of thiamin pyrophosphate (TPP) metabolism in Escherichia coli by using a TPP-sensing riboswitch that controls the expression of the fluorescent gfp reporter. By comparing different combinations of reporter fusions and TPP-sensing riboswitches, we determine key elements that are associated with strong TPP-dependent sensing. Furthermore, by using the Keio collection as a proxy for growth conditions differing in TPP levels, we perform a high-throughput screen analysis using high-density solid agar plates. Our study reveals several genes whose deletion leads to increased or decreased TPP levels. The approach developed here could be applicable to other riboswitches and reporter genes, thus representing a framework onto which further development could lead to highly sophisticated detection platforms allowing metabolic screens and identification of orphan riboswitches.


Subject(s)
Biosensing Techniques , Escherichia coli , Metabolic Networks and Pathways , Riboswitch , Thiamine Pyrophosphate , Riboswitch/genetics , Biosensing Techniques/methods , Escherichia coli/genetics , Escherichia coli/metabolism , Thiamine Pyrophosphate/metabolism , Metabolic Networks and Pathways/genetics , Green Fluorescent Proteins/metabolism , Green Fluorescent Proteins/genetics , Genes, Reporter , Gene Expression Regulation, Bacterial , Genome, Bacterial
15.
Chem Commun (Camb) ; 60(46): 5972-5975, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38767578

ABSTRACT

Here we report two novel synthetic riboswitches that respond to ASP2905 and theophylline and function in reconstituted cell-free protein synthesis (CFPS) system. We encapsulated the CFPS system as well as DNA-templated encoding reporter genes regulated by these orthogonal riboswitches inside liposomes, and achieved switchable and orthogonal control over gene expression by external stimulation with the cognate ligands.


Subject(s)
Artificial Cells , Riboswitch , Theophylline , Theophylline/chemistry , Artificial Cells/chemistry , Artificial Cells/metabolism , Liposomes/chemistry , Gene Expression Regulation , Protein Biosynthesis , Cell-Free System , Genes, Reporter , Ligands
16.
J Immunol Methods ; 529: 113682, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705372

ABSTRACT

BACKGROUND: The measurement of antigen-specific serum IgE is common in clinical assessments of type I allergies. However, the interaction between antigens and IgE won't invariably trigger mast cell activation. We previously developed the IgE crosslinking-induced luciferase expression (EXiLE) method using the RS-ATL8 mast cell line; however, the method may not be sensitive enough in some cases. METHODS: In this study, we introduced an NF-AT-regulated luciferase reporter gene into the RBL-2H3 rat mast cell line and expressed a chimeric high-affinity IgE receptor (FcεRI) α chain gene, comprising an extracellular domain from humans and transmembrane/intracellular domains from rats. RESULTS: We generated multiple clones expressing the chimeric receptor. Based on their responsiveness and proliferation, we selected the HuRa-40 clone. This cell line exhibited significantly elevated human α chain expression compared to RS-ATL8 cells, demonstrating a 10-fold enhancement of antigen-specific reactivity. Reproducibility across different batches and operators was excellent. Moreover, we observed a detectable response inhibition by an anti-allergy drugs (omalizumab and cyclosporin A). CONCLUSIONS: HuRa-40 cells-which carry the human-rat chimeric IgE receptor-comprise a valuable reporter cell line for the EXiLE method. Their versatility extends to various applications and facilitates high-throughput screening of anti-allergy drugs.


Subject(s)
Immunoglobulin E , Luciferases , Mast Cells , Receptors, IgE , Receptors, IgE/metabolism , Receptors, IgE/genetics , Receptors, IgE/immunology , Animals , Humans , Mast Cells/immunology , Mast Cells/metabolism , Rats , Immunoglobulin E/immunology , Luciferases/genetics , Luciferases/metabolism , Cell Line , Genes, Reporter , Reproducibility of Results , Receptors, Chimeric Antigen/genetics , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/metabolism
17.
Viruses ; 16(5)2024 05 11.
Article in English | MEDLINE | ID: mdl-38793642

ABSTRACT

Mouse adenoviruses (MAdV) play important roles in studying host-adenovirus interaction. However, easy-to-use reverse genetics systems are still lacking for MAdV. An infectious plasmid pKRMAV1 was constructed by ligating genomic DNA of wild-type MAdV-1 with a PCR product containing a plasmid backbone through Gibson assembly. A fragment was excised from pKRMAV1 by restriction digestion and used to generate intermediate plasmid pKMAV1-ER, which contained E3, fiber, E4, and E1 regions of MAdV-1. CMV promoter-controlled GFP expression cassette was inserted downstream of the pIX gene in pKMAV1-ER and then transferred to pKRMAV1 to generate adenoviral plasmid pKMAV1-IXCG. Replacement of transgene could be conveniently carried out between dual BstZ17I sites in pKMAV1-IXCG by restriction-assembly, and a series of adenoviral plasmids were generated. Recombinant viruses were rescued after transfecting linearized adenoviral plasmids to mouse NIH/3T3 cells. MAdV-1 viruses carrying GFP or firefly luciferase genes were characterized in gene transduction, plaque-forming, and replication in vitro or in vivo by observing the expression of reporter genes. The results indicated that replication-competent vectors presented relevant properties of wild-type MAdV-1 very well. By constructing viruses bearing exogenous fragments with increasing size, it was found that MAdV-1 could tolerate an insertion up to 3.3 kb. Collectively, a replication-competent MAdV-1 vector system was established, which simplified procedures for the change of transgene or modification of E1, fiber, E3, or E4 genes.


Subject(s)
Genetic Vectors , Plasmids , Virus Replication , Animals , Mice , Genetic Vectors/genetics , Plasmids/genetics , Adenoviridae/genetics , NIH 3T3 Cells , Cloning, Molecular , Genes, Reporter
18.
BMC Biotechnol ; 24(1): 22, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38664752

ABSTRACT

BACKGROUND: The advancement of AAV vectors into clinical testing has accelerated rapidly over the past two decades. While many of the AAV vectors being utilized in clinical trials are derived from natural serotypes, engineered serotypes are progressing toward clinical translation due to their enhanced tissue tropism and immune evasive properties. However, novel AAV vectors require formulation and stability testing to determine optimal storage conditions prior to their use in a clinical setting. RESULTS: Here, we evaluated the thermal stability of AAV6.2FF, a rationally engineered capsid with strong tropism for lung and muscle, in two different buffer formulations; phosphate buffered saline (PBS), or PBS supplemented with 0.001% non-ionic surfactant Pluronic F68 (PF-68). Aliquots of AAV6.2FF vector encoding the firefly luciferase reporter gene (AAV6.2FF-ffLuc) were incubated at temperatures ranging from -20°C to 55°C for varying periods of time and the impact on infectivity and particle integrity evaluated. Additionally, the impact of several rounds of freeze-thaw treatments on the infectivity of AAV6.2FF was investigated. Vector infectivity was measured by quantifying firefly luciferase expression in HEK 293 cells and AAV particle integrity was measured by qPCR quantification of encapsidated viral DNA. CONCLUSIONS: Our data demonstrate that formulating AAV6.2FF in PBS containing 0.001% PF-68 leads to increased stability and particle integrity at temperatures between -20℃ to 21℃ and protection against the destructive effects of freeze-thaw. Finally, AAV6.2FF-GFP formulated in PBS supplemented with 0.001% PF-68 displayed higher transduction efficiency in vivo in murine lung epithelial cells following intranasal administration than vector buffered in PBS alone further demonstrating the beneficial properties of PF-68.


Subject(s)
Dependovirus , Genetic Vectors , Poloxamer , Animals , Humans , HEK293 Cells , Poloxamer/pharmacology , Poloxamer/chemistry , Mice , Dependovirus/genetics , Genetic Vectors/genetics , Luciferases, Firefly/genetics , Luciferases, Firefly/metabolism , Temperature , Genes, Reporter
19.
Stem Cell Res Ther ; 15(1): 107, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38637896

ABSTRACT

BACKGROUND: The detailed transcriptomic profiles during human serotonin neuron (SN) differentiation remain elusive. The establishment of a reporter system based on SN terminal selector holds promise to produce highly-purified cells with an early serotonergic fate and help elucidate the molecular events during human SN development process. METHODS: A fifth Ewing variant (FEV)-EGFP reporter system was established by CRISPR/Cas9 technology to indicate SN since postmitotic stage. FACS was performed to purify SN from the heterogeneous cell populations. RNA-sequencing analysis was performed for cells at four key stages of differentiation (pluripotent stem cells, serotonergic neural progenitors, purified postmitotic SN and purifed mature SN) to explore the transcriptomic dynamics during SN differentiation. RESULTS: We found that human serotonergic fate specification may commence as early as day 21 of differentiation from human pluripotent stem cells. Furthermore, the transcriptional factors ZIC1, HOXA2 and MSX2 were identified as the hub genes responsible for orchestrating serotonergic fate determination. CONCLUSIONS: For the first time, we exposed the developmental transcriptomic profiles of human SN via FEV reporter system, which will further our understanding for the development process of human SN.


Subject(s)
Serotonin , Transcription Factors , Humans , Transcription Factors/genetics , Cell Differentiation/genetics , Gene Expression Profiling , Neurons , Genes, Reporter
20.
J Microbiol Methods ; 221: 106928, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38583783

ABSTRACT

The bicistronic expression system that utilizes fluorescent reporters has been demonstrated to be a straightforward method for detecting recombinant protein expression levels, particularly when compared to polyacrylamide gel electrophoresis and immunoblot analysis, which are tedious and labor-intensive. However, existing bicistronic reporter systems are less capable of quantitative measurement due to the lag in reporter expression and its negative impact on target protein. In this work, a plug and play bicistronic construct using mCherry as reporter was applied in the screening of optimal replicon and promoter for Sortase expression in Escherichia coli (E. coli). The bicistronic construct allowed the reporter gene and target open reading frame (ORF) to be co-transcribed under the same promoter, resulting in a highly positive quantitative correlation between the expression titer of Sortase and the fluorescent intensity (R2 > 0.97). With the correlation model, the titer of target protein can be quantified by noninvasively measuring the fluorescent intensity. On top of this, the expression of reporter has no significant effect on the yield of target protein, thus favoring a plug and play design for removing reporter gene to generate a plain plasmid for industrial use.


Subject(s)
Escherichia coli , Genes, Reporter , Luminescent Proteins , Plasmids , Promoter Regions, Genetic , Recombinant Proteins , Escherichia coli/genetics , Escherichia coli/metabolism , Luminescent Proteins/genetics , Plasmids/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Red Fluorescent Protein , Open Reading Frames , Gene Expression , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Genetic Vectors , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/metabolism , Gene Expression Regulation, Bacterial , Replicon/genetics
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