The metal cofactor zinc and interacting membranes modulate SOD1 conformation-aggregation landscape in an in vitro ALS Model
- CSIR-Indian Institute of Chemical Biology, India
- Harvard University, United States
- Jadavpur University, India
- National Institute of Science Education and Research (NISER), India
- Indian Institute of Technology Madras, India
Abstract
Aggregation of Cu-Zn superoxide dismutase (SOD1) is implicated in the motor neuron disease, ALS. Although more than 140 disease mutations of SOD1 are available, their stability or aggregation behaviors in membrane environment are not correlated with disease pathophysiology. Here, we use multiple mutational variants of SOD1 to show that the absence of Zn, and not Cu, significantly impacts membrane attachment of SOD1 through two loop regions facilitating aggregation driven by lipid induced conformational changes. These loop regions influence both the primary (through Cu intake) and the gain of function (through aggregation) of SOD1 presumably through a shared conformational landscape. Combining experimental and theoretical frameworks using representative ALS disease mutants, we develop a 'co-factor derived membrane association model' wherein mutational stress closer to the Zn (but not to the Cu) pocket is responsible for membrane association mediated toxic aggregation and survival time scale after ALS diagnosis.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files
Article and author information
Author details
Krishnananda Chattopadhyay
Funding
University Grants Commission (Fellowship)
- Achinta Sannigrahi
University Grants Commission (Fellowship)
- Sourav Chowdhury
Department of Biotechnology, Ministry of Science and Technology, India (BT/PR8475/BRB/10/1248/2013)
- Sanat Karmakar
Science and Engineering Research Board (EMR/2016/000310)
- Krishnananda Chattopadhyay
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Sannigrahi 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 metal cofactor zinc and interacting membranes modulate SOD1 conformation-aggregation landscape in an in vitro ALS Model
eLife 10:e61453.
https://doi.org/10.7554/eLife.61453
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