Large SOD1 aggregates, unlike trimeric SOD1, do not impact cell viability in a model of amyotrophic lateral sclerosis

Cheng Zhu, Matthew V. Beck, Jack D. Griffith, Mohanish Deshmukh, Nikolay V. Dokholyan

Research output: Contribution to journalArticle

15 Scopus citations

Abstract

Aberrant accumulation of misfolded Cu, Zn superoxide dismutase (SOD1) is a hallmark of SOD1-associated amyotrophic lateral sclerosis (ALS), an invariably fatal neurodegenerative disease. While recent discovery of nonnative trimeric SOD1-associated neurotoxicity has suggested a potential pathway for motor neuron impairment, it is yet unknown whether large, insoluble aggregates are cytotoxic. Here we designed SOD1 mutations that specifically stabilize either the fibrillar form or the trimeric state of SOD1. The designed mutants display elevated populations of fibrils or trimers correspondingly, as demonstrated by gel filtration chromatography and electron microscopy. The trimer-stabilizing mutant, G147P, promoted cell death, even more potently in comparison with the aggressive ALS-associated mutants A4V and G93A. In contrast, the fibril-stabilizing mutants, N53I and D101I, positively impacted the survival of motor neuron-like cells. Hence, we conclude the SOD1 oligomer and not the mature form of aggregated fibril is critical for the neurotoxic effects in the model of ALS. The formation of large aggregates is in competition with trimer formation, suggesting that aggregation may be a protective mechanism against formation of toxic oligomeric intermediates.

Original languageEnglish (US)
Pages (from-to)4661-4665
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume115
Issue number18
DOIs
StatePublished - May 1 2018

All Science Journal Classification (ASJC) codes

  • General

Fingerprint Dive into the research topics of 'Large SOD1 aggregates, unlike trimeric SOD1, do not impact cell viability in a model of amyotrophic lateral sclerosis'. Together they form a unique fingerprint.

  • Cite this