p62 overexpression induces TDP-43 cytoplasmic mislocalisation, aggregation and cleavage and neuronal death

Authors

A. D. Foster, Sir Charles Gairdner Hospital
L. L. Flynn, The University of Western Australia
C. Cluning, Sir Charles Gairdner Hospital
F. Cheng, Macquarie University
J. M. Davidson, Macquarie University
A. Lee, Macquarie University
N. Polain, The University of Western Australia
R. Mejzini, The University of Western Australia
N. Farrawell, University of Wollongong
J. J. Yerbury, University of Wollongong
R. Layfield, University of Nottingham
P. A. Akkari, The University of Western Australia
S. L. Rea, The University of Western Australia

Publication Name

Scientific Reports

Abstract

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) that exist on a spectrum of neurodegenerative disease. A hallmark of pathology is cytoplasmic TDP-43 aggregates within neurons, observed in 97% of ALS cases and ~ 50% of FTLD cases. This mislocalisation from the nucleus into the cytoplasm and TDP-43 cleavage are associated with pathology, however, the drivers of these changes are unknown. p62 is invariably also present within these aggregates. We show that p62 overexpression causes TDP-43 mislocalisation into cytoplasmic aggregates, and aberrant TDP-43 cleavage that was dependent on both the PB1 and ubiquitin-associated (UBA) domains of p62. We further show that p62 overexpression induces neuron death. We found that stressors (proteasome inhibition and arsenic) increased p62 expression and that this shifted the nuclear:cytoplasmic TDP-43 ratio. Overall, our study suggests that environmental factors that increase p62 may thereby contribute to TDP-43 pathology in ALS and FTLD.

Open Access Status

This publication may be available as open access

Volume

11

Issue

1

Article Number

11474

Funding Number

IG 1949

Funding Sponsor

Motor Neurone Disease Research Institute of Australia