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Published on: June 15, 2018
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A Novel ENU-Induced Mfn2 Mutation Causes Motor Deficits in Mice without Causing Peripheral Neuropathy
Timothy J Hines1, Janice Bailey2, Hedi Liu2
1The Jackson Laboratory, Bar Harbor, ME 04609, USA.
Biology
|July 29, 2023
Summary
A new mouse model with a mutation in the MFN2 gene exhibits a recessive motor disorder, impacting weight, activity, and muscle function. This model offers insights into MFN2
Area of Science:
- Mitochondrial biology
- Neurogenetics
- Molecular cell biology
Background:
- Mitochondrial dynamics, including fission and fusion, are crucial for cellular health.
- Mitofusins (MFN1 and MFN2) are key regulators of mitochondrial fusion.
- MFN2 mutations are linked to Charcot-Marie-Tooth disease type 2A (CMT2A) in humans.
Purpose of the Study:
- To characterize a novel ENU-induced mouse mutant with a recessive neuromuscular phenotype.
- To investigate the functional consequences of a specific MFN2 transmembrane domain mutation.
- To establish a new mouse model for studying MFN2-related disorders.
Main Methods:
- Phenotypic analysis of a novel ENU-induced mutant mouse line.
- Genetic mapping and sequencing to identify the causative mutation in Mfn2.
- Behavioral testing (rotarod, open field), physiological assays, and histological examination.
- Mitochondrial and bone analyses in mutant mice.
Main Results:
- Identified a missense mutation (Leu643Pro) in the MFN2 transmembrane domain.
- Mfn2 mutant mice displayed progressive motor deficits, weight loss, and reduced activity.
- Observed decreased mitochondrial diameter, mitochondrial DNA content, and MFN2 protein levels.
- Mutant mice showed mild bone defects (reduced cortical thickness) but largely normal nerve pathology.
Conclusions:
- The MFN2 Leu643Pro mutation causes a recessive motor phenotype in mice, accompanied by mitochondrial and bone abnormalities.
- This mouse model, despite lacking overt nerve pathology, is valuable for studying MFN2 function and related diseases.
- Highlights the role of the MFN2 transmembrane domain in motor function and mitochondrial integrity.
