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Zou W, Chezhian J, Yu T, Liu W, Vu J, Slone J, Huang T. Dissecting the Roles of the Nuclear and Mitochondrial Genomes in a Mouse Model of Autoimmune Diabetes. Diabetes 2024; 73:108-119. [PMID: 37847928 DOI: 10.2337/db23-0430] [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: 06/01/2023] [Accepted: 09/25/2023] [Indexed: 10/19/2023]
Abstract
Mitochondria, the organelles responsible for generating ATP in eukaryotic cells, have been previously implicated as a contributor to diabetes. However, mitochondrial proteins are encoded by both nuclear DNA (nDNA) and mtDNA. In order to better understand the relative contribution of each of these genomes to diabetes, a chimeric mitochondrial-nuclear exchange (MNX) mouse was created via pronuclear transfer carrying nDNA from a strain susceptible to type 1 diabetes (NOD/ShiLtJ) and mtDNA from nondiabetic C57BL/6J mice. Inheritance of the resulting heteroplasmic mtDNA mixture was then tracked across multiple generations, showing that offspring heteroplasmy generally followed that of the mother, with occasional large shifts consistent with an mtDNA bottleneck in the germ line. In addition, survival and incidence of diabetes in MNX mice were tracked and compared with those in unaltered NOD/ShiLtJ control mice. The results indicated improved survival and a delay in diabetes onset in the MNX mice, demonstrating that mtDNA has a critical influence on disease phenotype. Finally, enzyme activity assays showed that the NOD/ShiLtJ mice had significant hyperactivity of complex I of the electron transport chain relative to MNX mice, suggesting that a particular mtDNA variant (m.9461T>C) may be responsible for disease causation in the original NOD/ShiLtJ strain. ARTICLE HIGHLIGHTS Mitochondria have been previously implicated in diabetes, but the specific genetic factors remain unclear. To better understand the contributions of mitochondrial genes in nuclear DNA (nDNA) versus mtDNA, we created mitochondrial-nuclear exchange (MNX) mice carrying nDNA from a diabetic strain and mtDNA from nondiabetic mice. Long-term tracking of MNX mice showed occasional large shifts in heteroplasmy consistent with an mtDNA bottleneck in the germ line. In addition, the MNX mice showed improved survival and delayed incidence of diabetes relative to the unaltered diabetic mice, which appeared to be linked to the activity of respiratory complex I.
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Affiliation(s)
- Weiwei Zou
- Department of Obstetrics and Gynecology, Reproductive Medicine Center, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, China
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Janaki Chezhian
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
| | - Tenghui Yu
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
- Human Aging Research Institute, School of Life Science, Nanchang University, Nanchang, Jiangxi Province, China
| | - Wensheng Liu
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
| | - Jimmy Vu
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
| | - Jesse Slone
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY
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Hackett J, Gibson H, Frelinger J, Buntzman A. Using the Collaborative Cross and Diversity Outbred Mice in Immunology. Curr Protoc 2022; 2:e547. [PMID: 36066328 PMCID: PMC9612550 DOI: 10.1002/cpz1.547] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The Collaborative Cross (CC) and the Diversity Outbred (DO) stock mouse panels are the most powerful murine genetics tools available to the genetics community. Together, they combine the strength of inbred animal models with the diversity of outbred populations. Using the 63 CC strains or a panel of DO mice, each derived from the same 8 parental mouse strains, researchers can map genetic contributions to exceptionally complex immunological and infectious disease traits that would require far greater powering if performed by genome-wide association studies (GWAS) in human populations. These tools allow genes to be studied in heterozygous and homozygous states and provide a platform to study epistasis between interacting loci. Most importantly, once a quantitative phenotype is investigated and quantitative trait loci are identified, confirmatory genetic studies can be performed, which is often problematic using the GWAS approach. In addition, novel stable mouse models for immune phenotypes are often derived from studies utilizing the DO and CC mice that can serve as stronger model systems than existing ones in the field. The CC/DO systems have contributed to the fields of cancer immunology, autoimmunity, vaccinology, infectious disease, allergy, tissue rejection, and tolerance but have thus far been greatly underutilized. In this article, we present a recent review of the field and point out key areas of immunology that are ripe for further investigation and awaiting new CC/DO research projects. We also highlight some of the strong computational tools that have been developed for analyzing CC/DO genetic and phenotypic data. Additionally, we have formed a centralized community on the CyVerse infrastructure where immunogeneticists can utilize those software tools, collaborate with groups across the world, and expand the use of the CC and DO systems for investigating immunogenetic phenomena. © 2022 Wiley Periodicals LLC.
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Affiliation(s)
- Justin Hackett
- Barbara Ann Karmanos Cancer Institute, Hudson-Webber Cancer Research Center, Detroit, Michigan
| | - Heather Gibson
- Barbara Ann Karmanos Cancer Institute, Hudson-Webber Cancer Research Center, Detroit, Michigan
| | - Jeffrey Frelinger
- University of Arizona, Valley Fever Center for Excellence, Tucson, Arizona
- Department of Microbiology and Immunology, University of North Carolina System, Chapel Hill, North Carolina
| | - Adam Buntzman
- University of Arizona, BIO5 Institute, Valley Fever Center for Excellence, Tucson, Arizona
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