A non-mosaic transchromosomic mouse model of Down syndrome carrying the long arm of human chromosome 21
- Tottori University, Japan
- Johns Hopkins University School of Medicine, United States
- Yamazaki University of Animal Health Technology, Japan
- Tohoku University Graduate School of Medicine, Japan
- National Institute of Advanced Industrial Science and Technology, Japan
- RIKEN BioResource Research Center, Japan
- Zhejiang University, China
- John Hopkins University School of Medicine, United States
- California State University, United States
- Pennsylvania State University, United States
Abstract
Animal models of Down syndrome (DS), trisomic for human chromosome 21 (HSA21) genes or orthologs, provide insights into better understanding and treatment options. The only existing transchromosomic (Tc) mouse DS model, Tc1, carries a HSA21 with over 50 protein coding genes (PCGs) disrupted. Tc1 is mosaic, compromising interpretation of results. Here, we 'clone' the 34 MB long arm of HSA21 (HSA21q) as a mouse artificial chromosome (MAC). Through multiple steps of microcell-mediated chromosome transfer, we created a new Tc DS mouse model, Tc(HSA21q;MAC)1Yakaz ('TcMAC21'). TcMAC21 is not mosaic and contains 93% of HSA21q PCGs that are expressed and regulatable. TcMAC21 recapitulates many DS phenotypes including anomalies in heart, craniofacial skeleton and brain, molecular/cellular pathologies, and impairments in learning, memory and synaptic plasticity. TcMAC21 is the most complete genetic mouse model of DS extant and has potential for supporting a wide range of basic and preclinical research.
Data availability
All raw read data of TcMAC21 WGS were deposited to DDBJ Sequence Read Archive (DRA) under accession number DRA008337 and DRA008342
-
Analysis of DS mouseDDBJ Sequence Read Archive (DRA) ,DRA008337.
-
Analysis of DS mouseDDBJ Sequence Read Archive (DRA), DRA008342.
Article and author information
Author details
Joan T Richtsmeier
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R21HD098540-01)
- Roger H Reeves
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD038384)
- Roger H Reeves
Japan Society for the Promotion of Science (25221308)
- Mitsuo Oshimura
Core Research for Evolutional Science and Technology (JPMJCR18S4)
- Yasuhiro Kazuki
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All animal experiments were approved by the Institutional Animal Care and Use Committee (IACUC) protocols of Johns Hopkins University (#MO18M291), Tottori University (Permit Number: 06-S-102, 08-Y-69, 09-Y-24,11-Y-52, 13-Y-19, 14-Y-23, 15-Y-31, 16-Y-20, 17-Y-28, 19-Y-22, 20-Y-13), RIKEN BioResource Research Center (Permit Number: 08-005, 09-005, 10-005), and Tohoku University (Permit Number: 2013MdA-424)..
Copyright
© 2020, Kazuki et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 6,687
- views
-
- 758
- downloads
-
- 80
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
A non-mosaic transchromosomic mouse model of Down syndrome carrying the long arm of human chromosome 21
eLife 9:e56223.
https://doi.org/10.7554/eLife.56223
Further reading
-
- Cancer Biology
- Genetics and Genomics
Tyrosine kinases play a crucial role in cell proliferation and survival and are extensively investigated as targets for cancer treatment. However, the efficacy of most tyrosine kinase inhibitors (TKIs) in cancer therapy is limited due to resistance. In this study, we identify a synergistic combination therapy involving TKIs for the treatment of triple negative breast cancer. By employing pairwise tyrosine kinase knockout CRISPR screens, we identify FYN and KDM4 as critical targets whose inhibition enhances the effectiveness of TKIs, such as NVP-ADW742 (IGF-1R inhibitor), gefitinib (EGFR inhibitor), and imatinib (ABL inhibitor) both in vitro and in vivo. Mechanistically, treatment with TKIs upregulates the transcription of KDM4, which in turn demethylates H3K9me3 at FYN enhancer for FYN transcription. This compensatory activation of FYN and KDM4 contributes to the resistance against TKIs. FYN expression is associated with therapy resistance and persistence by demonstrating its upregulation in various experimental models of drug-tolerant persisters and residual disease following targeted therapy, chemotherapy, and radiotherapy. Collectively, our study provides novel targets and mechanistic insights that can guide the development of effective combinatorial targeted therapies, thus maximizing the therapeutic benefits of TKIs.
-
- Evolutionary Biology
- Genetics and Genomics
Chromosomal inversion polymorphisms can be common, but the causes of their persistence are often unclear. We propose a model for the maintenance of inversion polymorphism, which requires that some variants contribute antagonistically to two phenotypes, one of which has negative frequency-dependent fitness. These conditions yield a form of frequency-dependent disruptive selection, favoring two predominant haplotypes segregating alleles that favor opposing antagonistic phenotypes. An inversion associated with one haplotype can reduce the fitness load incurred by generating recombinant offspring, reinforcing its linkage to the haplotype and enabling both haplotypes to accumulate more antagonistic variants than expected otherwise. We develop and apply a forward simulator to examine these dynamics under a tradeoff between survival and male display. These simulations indeed generate inversion-associated haplotypes with opposing sex-specific fitness effects. Antagonism strengthens with time, and can ultimately yield karyotypes at surprisingly predictable frequencies, with striking genotype frequency differences between sexes and between developmental stages. To test whether this model may contribute to well-studied yet enigmatic inversion polymorphisms in Drosophila melanogaster, we track inversion frequencies in laboratory crosses to test whether they influence male reproductive success or survival. We find that two of the four tested inversions show significant evidence for the tradeoff examined, with In(3 R)K favoring survival and In(3 L)Ok favoring male reproduction. In line with the apparent sex-specific fitness effects implied for both of those inversions, In(3 L)Ok was also found to be less costly to the viability and/or longevity of males than females, whereas In(3 R)K was more beneficial to female survival. Based on this work, we expect that balancing selection on antagonistically pleiotropic traits may provide a significant and underappreciated contribution to the maintenance of natural inversion polymorphism.
