The critical role of membralin in postnatal motor neuron survival and disease
- Eugenom, Inc., United States
- Shanghai Yuanqi Clinical Lab Ltd., China
- Sanford-Burnham Medical Research Institute, United States
- University of California, Davis, United States
- Massachusetts General Hospital, United States
Abstract
Hitherto, membralin has been a protein of unknown function. Here, we show that membralin mutant mice manifest a severe and early-onset motor neuron disease in an autosomal recessive manner, dying by postnatal day 5-6. Selective death of lower motor neurons, including those innervating the limbs, intercostal muscles, and diaphragm, are predominantly responsible for this fatal phenotype. Neural expression of a membralin transgene completely rescues membralin mutant mice. Mechanistically, we show that membralin interacts with Erlin2, an endoplasmic reticulum (ER) membrane protein that is located in lipid rafts and known to be important in ER-associated protein degradation (ERAD). Accordingly, the degradation rate of ERAD substrates is attenuated in cells lacking membralin. Membralin mutations or deficiency in mouse models induce ER stress, rendering neurons more vulnerable to cell death. Our study reveals a critical role of membralin in motor neuron survival and suggests a novel mechanism for early-onset motor neuron disease.
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Ethics
Animal experimentation: All described procedures for animal were approved by the Institutional Animal Care and Use Committee of Sanford-Burnham Medical Research Institute and conducted in compliance with the Guide for the Care and Use of Laboratory Animals (Animal Use Form #14-060). Both sexes of mice were used for experiments and maintained in an institute facility accredited by the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC).
Copyright
© 2015, Yang 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.
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The critical role of membralin in postnatal motor neuron survival and disease
eLife 4:e06500.
https://doi.org/10.7554/eLife.06500
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