Therapeutic genetic variation revealed in diverse Hsp104 homologs
- University of Pennsylvania, United States
- The University of Alabama, United States
- Washington University in St Louis, United States
- Argonne National Laboratory, United States
Abstract
The AAA+ protein disaggregase, Hsp104, increases fitness under stress by reversing stress-induced protein aggregation. Natural Hsp104 variants might exist with enhanced, selective activity against neurodegenerative disease substrates. However, natural Hsp104 variation remains largely unexplored. Here, we screened a cross-kingdom collection of Hsp104 homologs in yeast proteotoxicity models. Prokaryotic ClpG reduced TDP-43, FUS, and a-synuclein toxicity, whereas prokaryotic ClpB and hyperactive variants were ineffective. We uncovered therapeutic genetic variation among eukaryotic Hsp104 homologs that specifically antagonized TDP-43 condensation and toxicity in yeast and TDP-43 aggregation in human cells. We also uncovered distinct eukaryotic Hsp104 homologs that selectively antagonized a-synuclein condensation and toxicity in yeast and dopaminergic neurodegeneration in C. elegans. Surprisingly, this therapeutic variation did not manifest as enhanced disaggregase activity, but rather as increased passive inhibition of aggregation of specific substrates. By exploring natural tuning of this passive Hsp104 activity, we elucidated enhanced, substrate-specific agents that counter proteotoxicity underlying neurodegeneration.
Data availability
All data generated or analysed during this study are included in the manuscript.
Article and author information
Author details
Meredith E Jackrel
Funding
National Institute of General Medical Sciences (R01GM099836)
- James Shorter
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, March 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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Therapeutic genetic variation revealed in diverse Hsp104 homologs
eLife 9:e57457.
https://doi.org/10.7554/eLife.57457
Further reading
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