Article

TDP-43 and FUS: a nuclear affair

Adolf-Butenandt-Institute, Biochemistry, Ludwig-Maximilians-University and German Center for Neurodegenerative Diseases (DZNE) Munich, Schillerstr. 44, 80336 Munich, Germany.
Trends in Neurosciences (Impact Factor: 12.9). 06/2011; 34(7). DOI: 10.1016/j.tins.2011.05.002
Source: PubMed

ABSTRACT Misfolded TAR DNA binding protein 43 (TDP-43) and Fused-In-Sarcoma (FUS) protein have recently been identified as pathological hallmarks of the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) characterized by the presence of ubiquitin-positive inclusions (FTLD-U). Although TDP-43 and FUS are normally located predominantly in the nucleus, pathological TDP-43 and FUS inclusions are mostly found in the cytosol. Cytosolic deposition is paralleled by a striking nuclear depletion of either protein. Based on a number of recent findings, we postulate that defects in nuclear import are an important step towards TDP-43 and FUS dysfunction. Failure of nuclear transport can arise from mutations within a nuclear localization signal or from age-related decline of nuclear import mechanisms. We propose that nuclear import defects in combination with additional hits, for example cellular stress and genetic risk factors, may be a central underlying cause of ALS and FTLD-U pathology.

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