TDP-43 pathology disrupts nuclear pore complexes and nucleocytoplasmic transport in ALS/FTD

Ching-Chieh Chou, Yi Zhang, Mfon E. Umoh, Spencer W. Vaughan, Ileana Lorenzini, Feilin Liu, Melissa Sayegh, Paul G. Donlin-Asp, Yu Han Chen, Duc M. Duong, Nicholas T. Seyfried, Maureen A. Powers, Thomas Kukar, Chadwick M. Hales, Marla Gearing, Nigel J. Cairns, Kevin B. Boylan, Dennis W. Dickson, Rosa Rademakers, Yong-Jie Zhang, Leonard Petrucelli, Rita Sattler, Daniela C. Zarnescu, Jonathan D. Glass, Wilfried Rossoll

The cytoplasmic mislocalization and aggregation of TAR DNA-binding protein-43 (TDP-43) is a common histopathological hallmark of the amyotrophic lateral sclerosis and frontotemporal dementia disease spectrum (ALS/FTD). However, the composition of aggregates and their contribution to the disease process remain unknown. Here we used proximity-dependent biotin identification (BioID) to interrogate the interactome of detergent-insoluble TDP-43 aggregates and found them enriched for components of the nuclear pore complex and nucleocytoplasmic transport machinery. Aggregated and disease-linked mutant TDP-43 triggered the sequestration and/or mislocalization of nucleoporins and transport factors, and interfered with nuclear protein import and RNA export in mouse primary cortical neurons, human fibroblasts and induced pluripotent stem cell-derived neurons. Nuclear pore pathology is present in brain tissue in cases of sporadic ALS and those involving genetic mutations in TARDBP and C9orf72. Our data strongly implicate TDP-43-mediated nucleocytoplasmic transport defects as a common disease mechanism in ALS/FTD.