IQ-Switch is a QF-based innocuous, silencing-free, and inducible gene switch system in zebrafish

AbstractThough various transgene expression switches have been adopted in a wide variety of organisms for basic and biomedical research, intrinsic obstacles of those existing systems, including toxicity and silencing, have been limiting their use in vertebrate transgenesis. Here we demonstrate a novel QF-based binary transgene switch (IQ-Switch) that is relatively free of driver toxicity and transgene silencing, and exhibits potent and highly tunable transgene activation by the chemical inducer tebufenozide, a non-toxic lipophilic molecule to developing zebrafish with negligible background. The interchangeable IQ-Switch makes it possible to elicit ubiquitous and tissue specific transgene expression in a spatiotemporal manner. We generated a RASopathy disease model using IQ-Switch and demonstrated that the RASopathy symptoms were ameliorated by the specific BRAF(V600E) inhibitor vemurafenib, validating the therapeutic use of the gene switch. The orthogonal IQ-Switch provides a state-of-the-art platform for flexible regulation of transgene expression in zebrafish, potentially applicable in cell-based systems and other model organisms.

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A safe and effective plant gene switch system for tissue-specific induction of gene expression in Arabidopsis thaliana and Brassica juncea

Transgenic Research ◽

10.1007/s11248-011-9572-0 ◽

2011 ◽

Vol 21 (4) ◽

pp. 879-883 ◽

Cited By ~ 8

Author(s):

Jaemo Yang ◽

M. Isabel Ordiz ◽

Ekaterina G. Semenyuk ◽

Brain Kelly ◽

Roger N. Beachy

Keyword(s):

Gene Expression ◽

Arabidopsis Thaliana ◽

Brassica Juncea ◽

Tissue Specific ◽

Plant Gene ◽

Specific Induction ◽

Switch System ◽

Gene Switch

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Consideration of Gut Microbiome in Murine Models of Diseases

Microorganisms ◽

10.3390/microorganisms9051062 ◽

2021 ◽

Vol 9 (5) ◽

pp. 1062

Author(s):

Chunye Zhang ◽

Craig L. Franklin ◽

Aaron C. Ericsson

Keyword(s):

Animal Models ◽

Mouse Models ◽

Biomedical Research ◽

Gut Microbiome ◽

Close Association ◽

Disease Model ◽

Potential Contributor ◽

Potential Factors ◽

Models Of Disease ◽

The Impact

The gut microbiome (GM), a complex community of bacteria, viruses, protozoa, and fungi located in the gut of humans and animals, plays significant roles in host health and disease. Animal models are widely used to investigate human diseases in biomedical research and the GM within animal models can change due to the impact of many factors, such as the vendor, husbandry, and environment. Notably, variations in GM can contribute to differences in disease model phenotypes, which can result in poor reproducibility in biomedical research. Variation in the gut microbiome can also impact the translatability of animal models. For example, standard lab mice have different pathogen exposure experiences when compared to wild or pet store mice. As humans have antigen experiences that are more similar to the latter, the use of lab mice with more simplified microbiomes may not yield optimally translatable data. Additionally, the literature describes many methods to manipulate the GM and differences between these methods can also result in differing interpretations of outcomes measures. In this review, we focus on the GM as a potential contributor to the poor reproducibility and translatability of mouse models of disease. First, we summarize the important role of GM in host disease and health through different gut–organ axes and the close association between GM and disease susceptibility through colonization resistance, immune response, and metabolic pathways. Then, we focus on the variation in the microbiome in mouse models of disease and address how this variation can potentially impact disease phenotypes and subsequently influence research reproducibility and translatability. We also discuss the variations between genetic substrains as potential factors that cause poor reproducibility via their effects on the microbiome. In addition, we discuss the utility of complex microbiomes in prospective studies and how manipulation of the GM through differing transfer methods can impact model phenotypes. Lastly, we emphasize the need to explore appropriate methods of GM characterization and manipulation.

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Could protein tertiary structure influence mammary transgene expression more than tissue specific codon usage?

Transgenic Research ◽

10.1007/s11248-010-9411-8 ◽

2010 ◽

Vol 19 (4) ◽

pp. 519-533

Author(s):

Zuyong He ◽

Yiqiang Zhao ◽

Gui Mei ◽

Ning Li ◽

Yaosheng Chen

Keyword(s):

Codon Usage ◽

Transgene Expression ◽

Tertiary Structure ◽

Tissue Specific ◽

Protein Tertiary Structure

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Translation elongation factor 1A2 is encoded by one of four closely related eef1a genes and is dispensable for survival in zebrafish

Bioscience Reports ◽

10.1042/bsr20194191 ◽

2020 ◽

Vol 40 (1) ◽

Author(s):

Nwamaka J. Idigo ◽

Dinesh C. Soares ◽

Catherine M. Abbott

Keyword(s):

De Novo ◽

Single Gene ◽

Expression Patterns ◽

Elongation Factor ◽

Model Organisms ◽

Translation Elongation Factor ◽

Translation Elongation ◽

Tissue Specific ◽

Elongation Factor 1A2 ◽

Mutant Lines

Abstract Zebrafish are valuable model organisms for the study of human single-gene disorders: they are genetically manipulable, their development is well understood, and mutant lines with measurable, disease-appropriate phenotypic abnormalities can be used for high throughput drug screening approaches. However, gene duplication events in zebrafish can result in redundancy of gene function, masking loss-of-function phenotypes and thus confounding this approach to disease modelling. Furthermore, recent studies have yielded contrasting results depending on whether specific genes are targeted using genome editing to make mutant lines, or whether morpholinos are used (morphants). De novo missense mutations in the human gene EEF1A2, encoding a tissue-specific translation elongation factor, cause severe neurodevelopmental disorders; there is a real need for a model system to study these disorders and we wanted to explore the possibility of a zebrafish model. We identified four eef1a genes and examined their developmental and tissue-specific expression patterns: eef1a1l1 is first to be expressed while eef1a2 is only detected later during development. We then determined the effects of introducing null mutations into translation elongation factor 1A2 (eEF1A2) in zebrafish using CRISPR/Cas9 gene editing, in order to compare the results with previously described morphants, and with severe neurodegenerative lethal phenotype of eEF1A2-null mice. In contrast with both earlier analyses in zebrafish using morpholinos and with the mouse eEF1A2-null mice, disruption of the eef1a2 gene in zebrafish is compatible with normal lifespan. The resulting lines, however, may provide a valuable platform for studying the effects of expression of mutant human eEF1A2 mRNA.

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Regulation of expression of a sheep metallothionein 1a-sheep growth hormone fusion gene in transgenic mice

Molecular and Cellular Biology ◽

10.1128/mcb.9.12.5473-5479.1989 ◽

1989 ◽

Vol 9 (12) ◽

pp. 5473-5479

Author(s):

C M Shanahan ◽

N W Rigby ◽

J D Murray ◽

J T Marshall ◽

C A Townrow ◽

...

Keyword(s):

Growth Hormone ◽

Transgenic Mice ◽

Mrna Expression ◽

Transgene Expression ◽

Fusion Gene ◽

Developmental Expression ◽

Regulation Of Expression ◽

Tissue Specific ◽

Transgenic Livestock ◽

Main Regulator

Transgenic mice containing a sheep metallothionein 1a-sheep growth hormone fusion gene exhibited low, tissue-specific basal levels of transgene mRNA expression, resulting in slightly elevated levels of circulating growth hormone that did not lead to a detectable increase in growth. After zinc stimulation, high levels of transgene mRNA expression were induced in a number of tissues; these levels correlated with increased levels of circulating growth hormone, resulting in growth increases of up to 1.5 times the levels of controls and unstimulated transgenic mice. After removal of the zinc stimulus, transgene expression and circulating growth hormone concentrations returned to basal levels. Additional evidence from the pattern of developmental expression of the transgene suggests that zinc is the main regulator of this promoter in mice. The demonstrated regulation and low basal level of expression of the sheep metallothionein 1a promoter make it a candidate for use in other mouse transgenic studies and for use in transgenic livestock, in which regulation of expression is essential.

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Cumate-Inducible Gene Expression System for Sphingomonads and Other Alphaproteobacteria

Applied and Environmental Microbiology ◽

10.1128/aem.02296-13 ◽

2013 ◽

Vol 79 (21) ◽

pp. 6795-6802 ◽

Cited By ~ 40

Author(s):

Andreas Kaczmarczyk ◽

Julia A. Vorholt ◽

Anne Francez-Charlot

Keyword(s):

Gene Expression ◽

Caulobacter Crescentus ◽

Paracoccus Denitrificans ◽

Expression System ◽

Model Organisms ◽

Inducible Gene Expression ◽

Gene Expression System ◽

Content Type ◽

Wide Range ◽

Inducible Gene

ABSTRACTTunable promoters represent a pivotal genetic tool for a wide range of applications. Here we present such a system for sphingomonads, a phylogenetically diverse group of bacteria that have gained much interest for their potential in bioremediation and their use in industry and for which no dedicated inducible gene expression system has been described so far. A strong, constitutive synthetic promoter was first identified through a genetic screen and subsequently combined with the repressor and the operator sites of thePseudomonas putidaF1cym/cmtsystem. The resulting promoter, termed PQ5, responds rapidly to the inducer cumate and shows a maximal induction ratio of 2 to 3 orders of magnitude in the different sphingomonads tested. Moreover, it was also functional in otherAlphaproteobacteria, such as the model organismsCaulobacter crescentus,Paracoccus denitrificans, andMethylobacterium extorquens. In the noninduced state, expression from PQ5is low enough to allow gene depletion analysis, as demonstrated with the essential genephyPofSphingomonassp. strain Fr1. A set of PQ5-based plasmids has been constructed allowing fusions to affinity tags or fluorescent proteins.

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Use of the microvine and plant gene switch system for functional studies of genes involved in the control of ripening initiation in Vitis vinifera

Acta Horticulturae ◽

10.17660/actahortic.2019.1248.27 ◽

2019 ◽

pp. 187-194

Author(s):

S. Gouthu ◽

L.G. Deluc

Keyword(s):

Vitis Vinifera ◽

Plant Gene ◽

Functional Studies ◽

Switch System ◽

Gene Switch

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miR2Diabetes: A Literature-Curated Database of microRNA Expression Patterns, in Diabetic Microvascular Complications

Genes ◽

10.3390/genes10100784 ◽

2019 ◽

Vol 10 (10) ◽

pp. 784 ◽

Cited By ~ 1

Author(s):

Sungjin Park ◽

SeongRyeol Moon ◽

Kiyoung Lee ◽

Ie Byung Park ◽

Dae Ho Lee ◽

...

Keyword(s):

Association Studies ◽

Microvascular Complications ◽

Expression Patterns ◽

Disease Model ◽

Model Organisms ◽

Web Interface ◽

Diabetic Microvascular Complications ◽

User Friendly ◽

Rats And Mice ◽

Kidney Liver

microRNAs (miRNAs) have been established as critical regulators of the pathogenesis of diabetes mellitus (DM), and diabetes microvascular complications (DMCs). However, manually curated databases for miRNAs, and DM (including DMCs) association studies, have yet to be established. Here, we constructed a user-friendly database, “miR2Diabetes,” equipped with a graphical web interface for simple browsing or searching manually curated annotations. The annotations in our database cover 14 DM and DMC phenotypes, involving 156 miRNAs, by browsing diverse sample origins (e.g., blood, kidney, liver, and other tissues). Additionally, we provide miRNA annotations for disease-model organisms (including rats and mice), of DM and DMCs, for the purpose of improving knowledge of the biological complexity of these pathologies. We assert that our database will be a comprehensive resource for miRNA biomarker studies, as well as for prioritizing miRNAs for functional validation, in DM and DMCs, with likely extension to other diseases.

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