Pathogenic Huntingtin aggregates alter actin organization and cellular stiffness resulting in stalled clathrin mediated endocytosis
- National Centre for Cell Science, India
- Indian Institute of Science Education and Research Pune, India
- Indian Institute of Technology Bombay, India
- UNSW Sydney, Australia
Abstract
Aggregation of mutant forms of Huntingtin is the underlying feature of neurodegeneration observed in Huntington's disorder. In addition to neurons, cellular processes in non-neuronal cell types are also shown to be affected. Cells expressing neurodegeneration-associated mutant proteins show altered uptake of ligands, suggestive of impaired endocytosis, in a manner as yet unknown. Using live cell imaging, we show that clathrin-mediated endocytosis (CME) is affected in Drosophila hemocytes and mammalian cells containing Huntingtin aggregates. This is also accompanied by alterations in the organization of the actin cytoskeleton resulting in increased cellular stiffness. Further, we find that Huntingtin aggregates sequester actin and actin-modifying proteins. Overexpression of Hip1 or Arp3 (actin-interacting proteins) could restore CME and cellular stiffness in cells containing Huntingtin aggregates. Neurodegeneration driven by pathogenic Huntingtin was also rescued upon overexpression of either Hip1 or Arp3 in Drosophila. Examination of other pathogenic aggregates revealed that TDP-43 also displayed defective CME, altered actin organization and increased stiffness, similar to pathogenic Huntingtin. Together, our results point to an intimate connection between dysfunctional CME, actin misorganization and increased cellular stiffness caused by alteration in the local intracellular environment by pathogenic aggregates.
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All data generated or analysed during this study are included in the manuscript and supporting files
Article and author information
Author details
Vaishnavi Ananthanarayanan
Funding
National Centre for Cell Science (NCCS/DIR/2018/24)
- Amitabha Majumdar
- Deepa Subramanyam
Government of India (CRG/2022/001891)
- Shivaprasad Patil
Wellcome Trust-DBT India Alliance (IA/I/13/2/501030)
- Amitabha Majumdar
Government of India (BT/PR25893/GET/119/174/2017)
- Amitabha Majumdar
EMBL Australia
- Vaishnavi Ananthanarayanan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Singh et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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Pathogenic Huntingtin aggregates alter actin organization and cellular stiffness resulting in stalled clathrin mediated endocytosis
eLife 13:e98363.
https://doi.org/10.7554/eLife.98363
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