Dataset Information

Transgene integration causes RARB downregulation in homozygous Tg4-42 mice.

ABSTRACT: Alzheimer's disease can be modelled by different transgenic mouse strains. To gain deeper insight into disease model mechanisms, the previously described Tg4-42 mouse was analysed for transgene integration. On RNA/DNA level the transgene integration resulted in more than 20 copy numbers and further caused a deletion of exon 2 of the retinoic acid receptor beta. These findings were also confirmed on protein level with highly decreased retinoic acid receptor beta protein levels in homozygous Tg4-42 mice and may have an impact on the previously described phenotype of homozygous Tg4-42 mice to be solely dependent on amyloid-ß 4-42 expression. Since hemizygous mice show no changes in RARB protein levels it can be concluded that the previously described phenotype of these mice should not be affected by the retinoic acid receptor beta gene knockout. In order to fully understand the results of transgenesis, it is extremely advisable to determine the genome integration site and the basic structure of the inserted transgenes. This can be carried out for instance by next-generation sequencing techniques. Our results thus suggest that a detailed characterization of new disease models using the latest genomics technologies prior to functional studies could be a valuable tool to avoid an unexpected genetic influence on the animals' phenotype that is not only based on the inserted transgene. This would also significantly improve the selection of mouse models that are best suited for therapeutic development and basic research.

SUBMITTER: Hinteregger B

PROVIDER: S-EPMC7156671 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Transgene integration causes RARB downregulation in homozygous Tg4-42 mice.

Hinteregger Barbara B Loeffler Tina T Flunkert Stefanie S Neddens Joerg J Birner-Gruenberger Ruth R Bayer Thomas A TA Madl Tobias T Hutter-Paier Birgit B

Scientific reports 20200414 1

Alzheimer's disease can be modelled by different transgenic mouse strains. To gain deeper insight into disease model mechanisms, the previously described Tg4-42 mouse was analysed for transgene integration. On RNA/DNA level the transgene integration resulted in more than 20 copy numbers and further caused a deletion of exon 2 of the retinoic acid receptor beta. These findings were also confirmed on protein level with highly decreased retinoic acid receptor beta protein levels in homozygous Tg4-4 ...[more]

PMID: 32286473

Similar Datasets

Project description:Zebrafish transgenesis is increasingly popular owing to the optical transparency and external development of embryos, which provide a scalable vertebrate model for in vivo experimentation. The ability to express transgenes in a tightly controlled spatio-temporal pattern is an important prerequisite for exploitation of zebrafish in a wide range of biomedical applications. However, conventional transgenesis methods are plagued by position effects: the regulatory environment of genomic integration sites leads to variation of expression patterns of transgenes driven by engineered cis-regulatory modules. This limitation represents a bottleneck when studying the precise function of cis-regulatory modules and their subtle variants or when various effector proteins are to be expressed for labelling and manipulation of defined sets of cells. Here, we provide evidence for the efficient elimination of variability of position effects by developing a PhiC31 integrase-based targeting method. To detect targeted integration events, a simple phenotype scoring of colour change in the lens of larvae is used. We compared PhiC31-based integration and Tol2 transgenesis in the analysis of the activity of a novel conserved enhancer from the developmentally regulated neural-specific esrrga gene. Reporter expression was highly variable among independent lines generated with Tol2, whereas all lines generated with PhiC31 into a single integration site displayed nearly identical, enhancer-specific reporter expression in brain nuclei. Moreover, we demonstrate that a modified integrase system can also be used for the detection of enhancer activity in transient transgenesis. These results demonstrate the power of the PhiC31-based transgene integration for the annotation and fine analysis of transcriptional regulatory elements and it promises to be a generally desirable tool for a range of applications, which rely on highly reproducible patterns of transgene activity in zebrafish.

Dataset Information

Transgene integration causes RARB downregulation in homozygous Tg4-42 mice.

Publications

Transgene integration causes RARB downregulation in homozygous Tg4-42 mice.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets