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Erhardt V, Hartig E, Lorenzo K, Megathlin HR, Tarchini B, Hosur V. Large-Scale Genome-Wide Optimization and Prediction of the Cre Recombinase System for Precise Genome Manipulation in Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.14.599022. [PMID: 38948742 PMCID: PMC11212873 DOI: 10.1101/2024.06.14.599022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
The Cre-Lox recombination system is a powerful tool in mouse genetics, offering spatial-temporal control over gene expression and facilitating the large-scale generation of conditional knockout mice. Its versatility also extends to other research models, such as rats, pigs, and zebrafish. However, the Cre-Lox technology presents a set of challenges that includes high costs, a time-intensive process, and the occurrence of unpredictable recombination events, which can lead to unexpected phenotypic outcomes. To better understand factors affecting recombination, we embarked on a systematic and genome-wide analysis of Cre-mediated recombination in mice. To ensure uniformity and reproducibility, we generated 11 novel strains with conditional alleles at the ROSA26 locus, utilizing a single inbred mouse strain background, C57BL/6J. We examined several factors influencing Cre-recombination, including the inter-loxP distance, mutant loxP sites, the zygosity of the conditional alleles, chromosomal location, and the age of the breeders. We discovered that the selection of the Cre-driver strain profoundly impacts recombination efficiency. We also found that successful and complete recombination is best achieved when loxP sites are spaced between 1 to 4 kb apart, with mutant loxP sites facilitating recombination at distances of 1 to 3 kb. Furthermore, we demonstrate that complete recombination does not occur at an inter-loxP distance of ≥ 15 kb with wildtype loxP sites, nor at a distance of ≥ 7 kb with mutant lox71/66 sites. Interestingly, the age of the Cre-driver mouse at the time of breeding emerged as a critical factor in recombination efficiency, with best results observed between 8 and 20 weeks old. Moreover, crossing heterozygous floxed alleles with the Cre-driver strain resulted in more efficient recombination than using homozygous floxed alleles. Lastly, maintaining an inter-loxP distance of 4 kb or less ensures efficient recombination of the conditional allele, regardless of the chromosomal location. While CRISPR/Cas has revolutionized genome editing in mice, Cre-Lox technology remains a cornerstone for the generation of sophisticated alleles and for precise control of gene expression in mice. The knowledge gained here will enable investigators to select a Cre-Lox approach that is most efficient for their desired outcome in the generation of both germline and non-germline mouse models of human disease, thereby reducing time and cost of Cre-Lox technology-mediated genome modification.
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Affiliation(s)
- Valerie Erhardt
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
| | - Elli Hartig
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
- Tufts University School of Medicine, Boston, MA
| | - Kristian Lorenzo
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
- The Roux Institute at Northeastern University, Portland, ME
| | - Hannah R Megathlin
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
- Graduate School of Biomedical Sciences and Engineering, UMaine, Orono, ME
| | - Basile Tarchini
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
- Tufts University School of Medicine, Boston, MA
| | - Vishnu Hosur
- The Jackson Laboratory for Mammalian Genetics, Bar Harbor, ME
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Chen H, Xie Y, Zhang M, Huang J, Jiang W, Zhang R, Li C, Du X, Chen H, Nie Q, Liang S, Tan Q, Yang J, Jin M, Huang S, Kuang L, Su N, Qi H, Luo X, Xu X, Deng C, Chen L, Luo F. An Hsp70 promoter-based mouse for heat shock-induced gene modulation. J Mol Med (Berl) 2024; 102:693-707. [PMID: 38492027 DOI: 10.1007/s00109-024-02433-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/11/2024] [Accepted: 02/13/2024] [Indexed: 03/18/2024]
Abstract
Physical therapy is extensively employed in clinical settings. Nevertheless, the absence of suitable animal models has resulted in an incomplete understanding of the in vivo mechanisms and cellular distribution that respond to physical stimuli. The objective of this research was to create a mouse model capable of indicating the cells affected by physical stimuli. In this study, we successfully established a mouse line based on the heat shock protein 70 (Hsp70) promoter, wherein the expression of CreERT2 can be induced by physical stimuli. Following stimulation of the mouse tail, ear, or cultured calvarias with heat shock (generated by heating, ultrasound, or laser), a distinct Cre-mediated excision was observed in cells stimulated by these physical factors with minimal occurrence of leaky reporter expression. The application of heat shock to Hsp70-CreERT2; FGFR2-P253R double transgenic mice or Hsp70-CreERT2 mice infected with AAV-BMP4 at calvarias induced the activation of Cre-dependent mutant FGFR2-P253R or BMP4 respectively, thereby facilitating the premature closure of cranial sutures or the repair of calvarial defects. This novel mouse line holds significant potential for investigating the underlying mechanisms of physical therapy, tissue repair and regeneration, lineage tracing, and targeted modulation of gene expression of cells in local tissue stimulated by physical factor at the interested time points. KEY MESSAGES: In the study, an Hsp70-CreERT2 transgenic mouse was generated for heat shock-induced gene modulation. Heat shock, ultrasound, and laser stimulation effectively activated Cre expression in Hsp70-CreERT2; reporter mice, which leads to deletion of floxed DNA sequence in the tail, ear, and cultured calvaria tissues of mice. Local laser stimuli on cultured calvarias effectively induce Fgfr2-P253R expression in Hsp70-mTmG-Fgfr2-P253R mice and result in accelerated premature closure of cranial suture. Heat shock activated AAV9-FLEX-BMP4 expression and subsequently promoted the repair of calvarial defect of Hsp70-CreERT2; Rosa26-mTmG mice.
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Affiliation(s)
- Hangang Chen
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Yangli Xie
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Mei Zhang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Junlan Huang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Wanling Jiang
- Department of Chinese Medicine Rehabilitation, Chongqing Emergency Medical Center, Chongqing University Central Hospital), Chongqing, 400042, China
| | - Ruobin Zhang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Can Li
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Xiaolan Du
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Hua Chen
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Qiang Nie
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Sen Liang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Qiaoyan Tan
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Jing Yang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Min Jin
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Shuo Huang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Liang Kuang
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Nan Su
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Huabing Qi
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China
| | - Xiaoqing Luo
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | - Xiaoling Xu
- Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Chuxia Deng
- Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Lin Chen
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China.
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China.
| | - Fengtao Luo
- Laboratory of Wound Repair and Rehabilitation Medicine, Daping Hospital, Third Military Medical University, Chongqing, 400042, China.
- State Key Laboratory of Trauma, Burn and Combined Injury, Third Military Medical University, Chongqing, 400038, China.
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Lanza DG, Mao J, Lorenzo I, Liao L, Seavitt JR, Ljungberg MC, Simpson EM, DeMayo FJ, Heaney JD. An oocyte-specific Cas9-expressing mouse for germline CRISPR/Cas9-mediated genome editing. Genesis 2024; 62:e23589. [PMID: 38523431 PMCID: PMC10987075 DOI: 10.1002/dvg.23589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/26/2024]
Abstract
Cas9 transgenes can be employed for genome editing in mouse zygotes. However, using transgenic instead of exogenous Cas9 to produce gene-edited animals creates unique issues including ill-defined transgene integration sites, the potential for prolonged Cas9 expression in transgenic embryos, and increased genotyping burden. To overcome these issues, we generated mice harboring an oocyte-specific, Gdf9 promoter driven, Cas9 transgene (Gdf9-Cas9) targeted as a single copy into the Hprt1 locus. The X-linked Hprt1 locus was selected because it is a defined integration site that does not influence transgene expression, and breeding of transgenic males generates obligate transgenic females to serve as embryo donors. Using microinjections and electroporation to introduce sgRNAs into zygotes derived from transgenic dams, we demonstrate that Gdf9-Cas9 mediates genome editing as efficiently as exogenous Cas9 at several loci. We show that genome editing efficiency is independent of transgene inheritance, verifying that maternally derived Cas9 facilitates genome editing. We also show that paternal inheritance of Gdf9-Cas9 does not mediate genome editing, confirming that Gdf9-Cas9 is not expressed in embryos. Finally, we demonstrate that off-target mutagenesis is equally rare when using transgenic or exogenous Cas9. Together, these results show that the Gdf9-Cas9 transgene is a viable alternative to exogenous Cas9.
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Affiliation(s)
- Denise G. Lanza
- Department of Molecular and Human Genetics, Baylor College of Medicine Houston, TX, USA 77030
| | - Jianqiang Mao
- Department of Molecular & Cellular Biology, Baylor College of Medicine Houston, TX, USA 77030
| | - Isabel Lorenzo
- Department of Molecular and Human Genetics, Baylor College of Medicine Houston, TX, USA 77030
| | - Lan Liao
- Department of Molecular & Cellular Biology, Baylor College of Medicine Houston, TX, USA 77030
| | - John R. Seavitt
- Department of Molecular and Human Genetics, Baylor College of Medicine Houston, TX, USA 77030
- Present address: The Jackson Laboratory 600 Main St., Bar Harbor, Maine, ME, USA 04609
| | - M. Cecilia Ljungberg
- Department of Pediatrics – Neurology, Baylor College of Medicine Houston, TX, USA 77030
- Duncan Neurological Research Institute, Texas Children’s Hospital Houston, TX, USA 77030
| | - Elizabeth M. Simpson
- Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital Department of Medical Genetics, The University of British Columbia Vancouver, British Columbia V5Z 4H4, Canada
| | - Francesco J. DeMayo
- Reproductive and Developmental Biology Laboratory National Institute of Environmental Health Sciences Research Triangle Park, NC, USA 27709
| | - Jason D. Heaney
- Department of Molecular and Human Genetics, Baylor College of Medicine Houston, TX, USA 77030
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine Houston, TX, USA 77030
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4
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Martinez D, Jiang E, Zhou Z. Overcoming genetic and cellular complexity to study the pathophysiology of X-linked intellectual disabilities. J Neurodev Disord 2024; 16:5. [PMID: 38424476 PMCID: PMC10902969 DOI: 10.1186/s11689-024-09517-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 02/04/2024] [Indexed: 03/02/2024] Open
Abstract
X-linked genetic causes of intellectual disability (ID) account for a substantial proportion of cases and remain poorly understood, in part due to the heterogeneous expression of X-linked genes in females. This is because most genes on the X chromosome are subject to random X chromosome inactivation (XCI) during early embryonic development, which results in a mosaic pattern of gene expression for a given X-linked mutant allele. This mosaic expression produces substantial complexity, especially when attempting to study the already complicated neural circuits that underly behavior, thus impeding the understanding of disease-related pathophysiology and the development of therapeutics. Here, we review a few selected X-linked forms of ID that predominantly affect heterozygous females and the current obstacles for developing effective therapies for such disorders. We also propose a genetic strategy to overcome the complexity presented by mosaicism in heterozygous females and highlight specific tools for studying synaptic and circuit mechanisms, many of which could be shared across multiple forms of intellectual disability.
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Affiliation(s)
- Dayne Martinez
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA
- Medical Scientist Training Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA
| | - Evan Jiang
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA
- Medical Scientist Training Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA
| | - Zhaolan Zhou
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA.
- Medical Scientist Training Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA.
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19102, USA.
- Intellectual and Developmental Disabilities Research Center, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
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5
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Mirjalili Mohanna SZ, Korecki AJ, Simpson EM. rAAV-PHP.B escapes the mouse eye and causes lethality whereas rAAV9 can transduce aniridic corneal limbal stem cells without lethality. Gene Ther 2023; 30:670-684. [PMID: 37072572 PMCID: PMC10506911 DOI: 10.1038/s41434-023-00400-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/28/2023] [Accepted: 04/05/2023] [Indexed: 04/20/2023]
Abstract
Recently safety concerns have been raised in connection with high doses of recombinant adeno-associated viruses (rAAV). Therefore, we undertook a series of experiments to test viral capsid (rAAV9 and rAAV-PHP.B), dose, and route of administration (intrastromal, intravitreal, and intravenous) focused on aniridia, a congenital blindness that currently has no cure. The success of gene therapy for aniridia may depend on the presence of functional limbal stem cells (LSCs) in the damaged aniridic corneas and whether rAAV can transduce them. Both these concerns were unknown, and thus were also addressed by our studies. For the first time, we report ataxia and lethality after intravitreal or intrastromal rAAV-PHP.B virus injections. We demonstrated virus escape from the eye and transduction of non-ocular tissues by rAAV9 and rAAV-PHP.B capsids. We have also shown that intrastromal and intravitreal delivery of rAAV9 can transduce functional LSCs, as well as all four PAX6-expressing retinal cell types in aniridic eye, respectively. Overall, lack of adverse events and successful transduction of LSCs and retinal cells makes it clear that rAAV9 is the capsid of choice for future aniridia gene therapy. Our finding of rAAV lethality after intraocular injections will be impactful for other researchers developing rAAV-based gene therapies.
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Affiliation(s)
- Seyedeh Zeinab Mirjalili Mohanna
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC, Canada
- Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada
| | - Andrea J Korecki
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC, Canada
| | - Elizabeth M Simpson
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC, Canada.
- Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada.
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6
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Zhao C, Ries C, Du Y, Zhang J, Sakimura K, Itoi K, Deussing JM. Differential CRH expression level determines efficiency of Cre- and Flp-dependent recombination. Front Neurosci 2023; 17:1163462. [PMID: 37599997 PMCID: PMC10434532 DOI: 10.3389/fnins.2023.1163462] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 07/21/2023] [Indexed: 08/22/2023] Open
Abstract
Corticotropin-releasing hormone expressing (CRH+) neurons are distributed throughout the brain and play a crucial role in shaping the stress responses. Mouse models expressing site-specific recombinases (SSRs) or reporter genes are important tools providing genetic access to defined cell types and have been widely used to address CRH+ neurons and connected brain circuits. Here, we investigated a recently generated CRH-FlpO driver line expanding the CRH system-related tool box. We directly compared it to a previously established and widely used CRH-Cre line with respect to the FlpO expression pattern and recombination efficiency. In the brain, FlpO mRNA distribution fully recapitulates the expression pattern of endogenous Crh. Combining both Crh locus driven SSRs driver lines with appropriate reporters revealed an overall coherence of respective spatial patterns of reporter gene activation validating CRH-FlpO mice as a valuable tool complementing existing CRH-Cre and reporter lines. However, a substantially lower number of reporter-expressing neurons was discerned in CRH-FlpO mice. Using an additional CRH reporter mouse line (CRH-Venus) and a mouse line allowing for conversion of Cre into FlpO activity (CAG-LSL-FlpO) in combination with intersectional and subtractive mouse genetic approaches, we were able to demonstrate that the reduced number of tdTomato reporter expressing CRH+ neurons can be ascribed to the lower recombination efficiency of FlpO compared to Cre recombinase. This discrepancy particularly manifests under conditions of low CRH expression and can be overcome by utilizing homozygous CRH-FlpO mice. These findings have direct experimental implications which have to be carefully considered when targeting CRH+ neurons using CRH-FlpO mice. However, the lower FlpO-dependent recombination efficiency also entails advantages as it provides a broader dynamic range of expression allowing for the visualization of cells showing stress-induced CRH expression which is not detectable in highly sensitive CRH-Cre mice as Cre-mediated recombination has largely been completed in all cells generally possessing the capacity to express CRH. These findings underscore the importance of a comprehensive evaluation of novel SSR driver lines prior to their application.
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Affiliation(s)
- Chen Zhao
- Molecular Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Clemens Ries
- Molecular Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Ying Du
- Molecular Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Jingwei Zhang
- Molecular Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Kenji Sakimura
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Keiichi Itoi
- Super-Network Brain Physiology, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Jan M. Deussing
- Molecular Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
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7
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Peeters S, Leung T, Fornes O, Farkas R, Wasserman W, Brown C. Refining the genomic determinants underlying escape from X-chromosome inactivation. NAR Genom Bioinform 2023; 5:lqad052. [PMID: 37260510 PMCID: PMC10227363 DOI: 10.1093/nargab/lqad052] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/01/2023] [Accepted: 05/19/2023] [Indexed: 06/02/2023] Open
Abstract
X-chromosome inactivation (XCI) epigenetically silences one X chromosome in every cell in female mammals. Although the majority of X-linked genes are silenced, in humans 20% or more are able to escape inactivation and continue to be expressed. Such escape genes are important contributors to sex differences in gene expression, and may impact the phenotypes of X aneuploidies; yet the mechanisms regulating escape from XCI are not understood. We have performed an enrichment analysis of transcription factor binding on the X chromosome, providing new evidence for enriched factors at the transcription start sites of escape genes. The top escape-enriched transcription factors were detected at the RPS4X promoter, a well-described human escape gene previously demonstrated to escape from XCI in a transgenic mouse model. Using a cell line model system that allows for targeted integration and inactivation of transgenes on the mouse X chromosome, we further assessed combinations of RPS4X promoter and genic elements for their ability to drive escape from XCI. We identified a small transgenic construct of only 6 kb capable of robust escape from XCI, establishing that gene-proximal elements are sufficient to permit escape, and highlighting the additive effect of multiple elements that work together in a context-specific fashion.
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Affiliation(s)
- Samantha Peeters
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tiffany Leung
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Oriol Fornes
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rachelle A Farkas
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wyeth W Wasserman
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carolyn J Brown
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
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8
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Yamamoto M, Stoessel SJ, Yamamoto S, Goldhamer DJ. Overexpression of Wild-Type ACVR1 in Fibrodysplasia Ossificans Progressiva Mice Rescues Perinatal Lethality and Inhibits Heterotopic Ossification. J Bone Miner Res 2022; 37:2077-2093. [PMID: 35637634 PMCID: PMC9708949 DOI: 10.1002/jbmr.4617] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 04/22/2022] [Accepted: 05/28/2022] [Indexed: 11/07/2022]
Abstract
Fibrodysplasia ossificans progressiva (FOP) is a devastating disease of progressive heterotopic bone formation for which effective treatments are currently unavailable. FOP is caused by dominant gain-of-function mutations in the receptor ACVR1 (also known as ALK2), which render the receptor inappropriately responsive to activin ligands. In previous studies, we developed a genetic mouse model of FOP that recapitulates most clinical aspects of the disease. In this model, genetic loss of the wild-type Acvr1 allele profoundly exacerbated heterotopic ossification, suggesting the hypothesis that the stoichiometry of wild-type and mutant receptors dictates disease severity. Here, we tested this model by producing FOP mice that conditionally overexpress human wild-type ACVR1. Injury-induced heterotopic ossification (HO) was completely blocked in FOP mice when expression of both the mutant and wild-type receptor were targeted to Tie2-positive cells, which includes fibro/adipogenic progenitors (FAPs). Perinatal lethality of Acvr1R206H/+ mice was rescued by constitutive ACVR1 overexpression, and these mice survived to adulthood at predicted Mendelian frequencies. Constitutive overexpression of ACVR1 also provided protection from spontaneous abnormal skeletogenesis, and the incidence and severity of injury-induced HO in these mice was dramatically reduced. Analysis of pSMAD1/5/8 signaling both in cultured cells and in vivo indicates that ACVR1 overexpression functions cell-autonomously by reducing osteogenic signaling in response to activin A. We propose that ACVR1 overexpression inhibits HO by decreasing the abundance of ACVR1(R206H)-containing signaling complexes at the cell surface while increasing the representation of activin-A-bound non-signaling complexes comprised of wild-type ACVR1. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Masakazu Yamamoto
- Department of Molecular and Cell BiologyUniversity of Connecticut Stem Cell Institute, University of ConnecticutStorrsCTUSA
| | - Sean J Stoessel
- Department of Molecular and Cell BiologyUniversity of Connecticut Stem Cell Institute, University of ConnecticutStorrsCTUSA
| | - Shoko Yamamoto
- Department of Molecular and Cell BiologyUniversity of Connecticut Stem Cell Institute, University of ConnecticutStorrsCTUSA
| | - David J Goldhamer
- Department of Molecular and Cell BiologyUniversity of Connecticut Stem Cell Institute, University of ConnecticutStorrsCTUSA
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9
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Namiki T, Kamoshita M, Kageyama A, Terakawa J, Ito J, Kashiwazaki N. Utility of progesterone receptor-ires-Cre to generate conditional knockout mice for uterine study. Anim Sci J 2021; 92:e13615. [PMID: 34402137 PMCID: PMC9286405 DOI: 10.1111/asj.13615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/13/2021] [Accepted: 07/26/2021] [Indexed: 11/27/2022]
Abstract
In mice, the conditional knockout strategy using the Cre-loxP system is useful for various types of research. The Cre mouse line with progesterone receptor promoter (PgrCre ) has been widely used to produce specific uterine gene-deficient mice, but in the Cre line, endogenous Pgr gene is replaced by Cre recombinase gene, which makes the breeding of homozygous mice (PgrCre/Cre ) difficult because they are infertile. Yang et al. (2013, https://10.1016/j.cell.2013.04.017) reported the generation of another PgriresCre mouse line that still has endogenous Pgr gene, and they inserted Cre recombinase downstream of the Pgr gene via an internal ribosome entry site (IRES). It is possible that this new PgriresCre line would be useful for uterine research as the mice can be bred as homozygotes (PgriresCre/iresCre ). Herein, we confirmed the PgriresCre mice effectively directed recombination in the female reproductive tract and was capable of genetic alteration in the endometrium that enables the studies of its uterine function. Our findings demonstrate that the new PgriresCre mouse line is also useful for the generation of uterine-specific knockout mice. The findings using PgriresCre mouse will contribute to the understanding of reproductive systems and diseases in humans and domestic animals.
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Affiliation(s)
- Takafumi Namiki
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan
| | - Maki Kamoshita
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan
| | - Atsuko Kageyama
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan
| | - Jumpei Terakawa
- Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan.,Laboratory of Toxicology, School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Junya Ito
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan.,Center for Human and Animal Symbiosis Science, Azabu University, Sagamihara, Japan
| | - Naomi Kashiwazaki
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan
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10
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Herron RS, Hwang HW. Comprehensive profiling of mRNA polyadenylation in specific cell types in vivo by cTag-PAPERCLIP. Methods Enzymol 2021; 655:165-184. [PMID: 34183120 DOI: 10.1016/bs.mie.2021.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to generate cell-type specific mRNA polyadenylation (pA) maps from complex tissues is crucial for understanding how alternative polyadenylation (APA) is regulated in individual cell types in their physiological environment under different conditions. In this chapter, we discuss cTag-PAPERCLIP, a recently developed method combining the well-established CLIP (crosslinking immunoprecipitation) technique and the Cre-lox system to achieve customized cell-type specific APA profiling from mouse tissue without cell purification or enrichment. In cTag-PAPERCLIP, selective expression of GFP-tagged poly(A) binding protein (PABP-GFP) in the desired cell type is achieved through Cre-mediated activation of a latent knock-in allele of PABP-GFP. Immunoprecipitation of PABP-GFP then allows mRNA 3' end fragments in the desired cell type to be specifically retrieved from ultraviolet (UV)-irradiated whole tissue lysate. The mRNA fragments are subsequently turned into a cDNA library to provide a comprehensive APA map and an mRNA expression profile of the chosen cell type through deep sequencing.
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Affiliation(s)
- R Samuel Herron
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA, United States
| | - Hun-Way Hwang
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA, United States.
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11
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Xie Z, McGrath C, Sankaran J, Styner M, Little-Letsinger S, Dudakovic A, van Wijnen AJ, Rubin J, Sen B. Low-Dose Tamoxifen Induces Significant Bone Formation in Mice. JBMR Plus 2021; 5:e10450. [PMID: 33778320 PMCID: PMC7990151 DOI: 10.1002/jbm4.10450] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 12/31/2022] Open
Abstract
Use of the selective estrogen receptor modulator Tamoxifen (TAM) is a mainstay to induce conditional expression of Cre recombinase in transgenic laboratory mice. To excise β‐cateninfl/fl in 28‐day‐old male and female Prrx1‐CreER/β‐cateninfl/fl mice (C57BL/6), we utilized TAM at 150 mg/kg; despite β‐catenin knockout in MSC, we found a significant increase in trabecular and cortical bone volume in all genders. Because TAM was similarly anabolic in KO and control mice, we investigated a dose effect on bone formation by treating wild‐type mice (WT C57BL/6, 4 weeks) with TAM (total dose 0, 20, 40, 200 mg/kg via four injections). TAM increased bone in a dose‐dependent manner analyzed by micro–computed tomography (μCT), which showed that, compared to control, 20 mg/kg TAM increased femoral bone volume fraction (bone volume/total volume [BV/TV]) (21.6% ± 1.5% to 33% ± 2.5%; 153%, p < 0.005). With TAM 40 mg/kg and 200 mg/kg, BV/TV increased to 48.1% ± 4.4% (223%, p < 0.0005) and 58% ± 3.8% (269%, p < 0.0001) respectively, compared to control. Osteoblast markers increased with 200 mg/kg TAM: Dlx5 (224%, p < 0.0001), Alp (166%, p < 0.0001), Bglap (223%, p < 0.0001), and Sp7 (228%, p < 0.0001). Osteoclasts per bone surface (Oc#/BS) nearly doubled at the lowest TAM dose (20 mg/kg), but decreased to <20% control with 200 mg/kg TAM. Our data establish that use of TAM at even very low doses to excise a floxed target in postnatal mice has profound effects on trabecular and cortical bone formation. As such, TAM treatment is a major confounder in the interpretation of bone phenotypes in conditional gene knockout mouse models. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Zhihui Xie
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Cody McGrath
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Jeyantt Sankaran
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Maya Styner
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | | | - Amel Dudakovic
- Department of Orthopedic Surgery and Biochemistry and Molecular Biology Mayo Clinic Rochester MN USA
| | - Andre J van Wijnen
- Department of Orthopedic Surgery and Biochemistry and Molecular Biology Mayo Clinic Rochester MN USA
| | - Janet Rubin
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Buer Sen
- Department of Medicine University of North Carolina Chapel Hill NC USA
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12
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Korecki AJ, Cueva-Vargas JL, Fornes O, Agostinone J, Farkas RA, Hickmott JW, Lam SL, Mathelier A, Zhou M, Wasserman WW, Di Polo A, Simpson EM. Human MiniPromoters for ocular-rAAV expression in ON bipolar, cone, corneal, endothelial, Müller glial, and PAX6 cells. Gene Ther 2021; 28:351-372. [PMID: 33531684 PMCID: PMC8222000 DOI: 10.1038/s41434-021-00227-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/17/2020] [Accepted: 01/15/2021] [Indexed: 02/06/2023]
Abstract
Small and cell-type restricted promoters are important tools for basic and preclinical research, and clinical delivery of gene therapies. In clinical gene therapy, ophthalmic trials have been leading the field, with over 50% of ocular clinical trials using promoters that restrict expression based on cell type. Here, 19 human DNA MiniPromoters were bioinformatically designed for rAAV, tested by neonatal intravenous delivery in mouse, and successful MiniPromoters went on to be tested by intravitreal, subretinal, intrastromal, and/or intravenous delivery in adult mouse. We present promoter development as an overview for each cell type, but only show results in detail for the recommended MiniPromoters: Ple265 and Ple341 (PCP2) ON bipolar, Ple349 (PDE6H) cone, Ple253 (PITX3) corneal stroma, Ple32 (CLDN5) endothelial cells of the blood-retina barrier, Ple316 (NR2E1) Müller glia, and Ple331 (PAX6) PAX6 positive. Overall, we present a resource of new, redesigned, and improved MiniPromoters for ocular gene therapy that range in size from 784 to 2484 bp, and from weaker, equal, or stronger in strength relative to the ubiquitous control promoter smCBA. All MiniPromoters will be useful for therapies involving small regulatory RNA and DNA, and proteins ranging from 517 to 1084 amino acids, representing 62.9-90.2% of human proteins.
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Affiliation(s)
- Andrea J. Korecki
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Jorge L. Cueva-Vargas
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Oriol Fornes
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Jessica Agostinone
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Rachelle A. Farkas
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Jack W. Hickmott
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Siu Ling Lam
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Anthony Mathelier
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Michelle Zhou
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Wyeth W. Wasserman
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Adriana Di Polo
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Elizabeth M. Simpson
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
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13
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Mirjalili Mohanna SZ, Hickmott JW, Lam SL, Chiu NY, Lengyell TC, Tam BM, Moritz OL, Simpson EM. Germline CRISPR/Cas9-Mediated Gene Editing Prevents Vision Loss in a Novel Mouse Model of Aniridia. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 17:478-490. [PMID: 32258211 PMCID: PMC7114625 DOI: 10.1016/j.omtm.2020.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 03/09/2020] [Indexed: 12/18/2022]
Abstract
Aniridia is a rare eye disorder, which is caused by mutations in the paired box 6 (PAX6) gene and results in vision loss due to the lack of a long-term vision-saving therapy. One potential approach to treating aniridia is targeted CRISPR-based genome editing. To enable the Pax6 small eye (Sey) mouse model of aniridia, which carries the same mutation found in patients, for preclinical testing of CRISPR-based therapeutic approaches, we endogenously tagged the Sey allele, allowing for the differential detection of protein from each allele. We optimized a correction strategy in vitro then tested it in vivo in the germline of our new mouse to validate the causality of the Sey mutation. The genomic manipulations were analyzed by PCR, as well as by Sanger and next-generation sequencing. The mice were studied by slit lamp imaging, immunohistochemistry, and western blot analyses. We successfully achieved both in vitro and in vivo germline correction of the Sey mutation, with the former resulting in an average 34.8% ± 4.6% SD correction, and the latter in restoration of 3xFLAG-tagged PAX6 expression and normal eyes. Hence, in this study we have created a novel mouse model for aniridia, demonstrated that germline correction of the Sey mutation alone rescues the mutant phenotype, and developed an allele-distinguishing CRISPR-based strategy for aniridia.
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Affiliation(s)
- Seyedeh Zeinab Mirjalili Mohanna
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada.,Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada
| | - Jack W Hickmott
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada.,Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada
| | - Siu Ling Lam
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Nina Y Chiu
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada.,Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada
| | - Tess C Lengyell
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Beatrice M Tam
- Department of Ophthalmology and Visual Sciences and Centre for Macular Research, The University of British Columbia, Vancouver, BC, Canada
| | - Orson L Moritz
- Department of Ophthalmology and Visual Sciences and Centre for Macular Research, The University of British Columbia, Vancouver, BC, Canada
| | - Elizabeth M Simpson
- Centre for Molecular Medicine and Therapeutics at British Columbia Children's Hospital, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada.,Department of Medical Genetics, The University of British Columbia, Vancouver, BC, Canada
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14
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Cui LJ, Chen WH, Liu AL, Han X, Jiang SX, Yuan F, Zhong YM, Yang XL, Weng SJ. nGnG Amacrine Cells and Brn3b-negative M1 ipRGCs are Specifically Labeled in the ChAT-ChR2-EYFP Mouse. Invest Ophthalmol Vis Sci 2020; 61:14. [PMID: 32049344 PMCID: PMC7326507 DOI: 10.1167/iovs.61.2.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Experimental access to specific cell subtypes is essential for deciphering the complexity of retinal networks. Here, we characterized the selective labeling, caused by ectopic transgene expression, of two atypical retinal neurons in the ChAT-Channelrhodopsin-2 (ChR2)-EYFP mouse. Methods Retinal sections and flat-mounts were prepared for double-staining immunohistochemistry with antibodies against EYFP and various neuronal markers. Sagittal/coronal brain slices were made to visualize EYFP signals in central nuclei. Whole-cell recordings were conducted to test the functionality of ChR2. Results Two populations of EYFP-positive retinal cells were observed. The inner nuclear layer (INL)-located one (type I cell) distributed regularly throughout the entire retina, whereas the ganglion cell layer (GCL)-residing one (type II cell) was restricted ventrally. None of them was cholinergic, as evidenced by the complete absence of ChAT immunoreactivity. Type I cells were immunolabeled by the amacrine marker syntaxin. However, the vast majority of them were neither positive to GABA/GAD65, nor to GlyT1/glycine, suggesting that they were non-GABAergic non-glycinergic amacrine cells (nGnG ACs), which was confirmed by double-labeling with the nGnG AC marker PPP1R17. Type II cells were immunopositive to melanopsin, but not to Brn3a or Brn3b. They possessed dendrites stratifying in the outermost inner plexiform layer (IPL) and axons projecting to the suprachiasmatic nucleus (SCN) rather than the olivary pretectal nucleus (OPN), suggesting that they belonged to a Brn3b-negative subset of M1-type intrinsically photosensitive retinal ganglion cells (ipRGCs). Glutamatergic transmission-independent photocurrents were elicited in EYFP-positive cells, indicating the functional expression of ChR2. Conclusions The ChAT-ChR2-EYFP retina exhibits ectopic, but functional, transgene expression in nGnG ACs and SCN-innervating M1 ipRGCs, thus providing an ideal tool to achieve efficient labeling and optogenetic manipulation of these cells.
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