UBQLN2 restrains the domesticated retrotransposon PEG10 to maintain neuronal health in ALS
- University of Colorado Boulder, United States
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive motor neuron dysfunction and loss. A portion of ALS cases are caused by mutation of the proteasome shuttle factor Ubiquilin 2 (UBQLN2), but the molecular pathway leading from UBQLN2 dysfunction to disease remains unclear. Here, we demonstrate that UBQLN2 regulates the domesticated gag-pol retrotransposon 'paternally expressed gene 10' (PEG10) in human cells and tissues. In cells, the PEG10 gag-pol protein cleaves itself in a mechanism reminiscent of retrotransposon self-processing to generate a liberated 'nucleocapsid' fragment, which uniquely localizes to the nucleus and changes the expression of genes involved in axon remodeling. In spinal cord tissue from ALS patients, PEG10 gag-pol is elevated compared to healthy controls. These findings implicate the retrotransposon-like activity of PEG10 as a contributing mechanism in ALS through regulation of gene expression, and restraint of PEG10 as a primary function of UBQLN2.
Data availability
Figure 6 - Source Data 1 contains the normalized counts from RNA-Seq data used to generate figures. Figure 8 - Source Data 1 contains the abundance counts from proteomics data used to generate figures. Sequencing data have been deposited in the Gene Expression Omnibus (GEO) at GSE227789. Proteomics data is available on PRIDE at PXD031964. Analysis code for microscopy quantitation can be obtained from https://github.com/jwtay1/PEG10-image-analysis/. All other data is available in the manuscript or source materials. Correspondence and material requests should be directed to A. M. Whiteley (alexandra.whiteley@colorado.edu).
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Gene expression changes in HEK293 cells following PEG10 overexpression.NCBI Gene Expression Omnibus, GSE227789.
Article and author information
Author details
Christopher C Ebmeier
Alexandra Whiteley
Funding
National Institute of General Medical Sciences (T32GM142607)
- Julia E Roberts
- Autumn M Matthews
National Cancer Institute (T32CA174648)
- G Aaron Holling
Biological Sciences Initiative
- Elizabeth Ung
- Cristina I Lau
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Black 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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UBQLN2 restrains the domesticated retrotransposon PEG10 to maintain neuronal health in ALS
eLife 12:e79452.
https://doi.org/10.7554/eLife.79452
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