title: Tunicamycin produces TDP-43 cytoplasmic inclusions in cultured brain organotypic slices.
abstract: The cellular distribution of TAR DNA binding protein (TDP-43) is disrupted in several neurodegenerative disorders, including frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U subtype) and amyotrophic lateral sclerosis (ALS). In these conditions, TDP-43 is found in neuronal cytoplasmic inclusions, with loss of the normal nuclear expression. The mechanisms leading to TDP-43 redistribution and its role in disease pathophysiology remain unknown. We describe an in vitro neural tissue model that reproduces TDP-43 relocalization and inclusion formation. Two week-old coronal organotypic mouse brain slice cultures were treated with tunicamycin for 7 days. In cortical regions of treated slice cultures, cytoplasmic inclusions of TDP-43 immunoreactivity were observed, with loss of nuclear TDP-43 immunoreactivity. These inclusions were found in both astrocytes and neurons, and were of both skein-like and round morphologies. In contrast, TDP-43 cytoplasmic inclusions were not found in slices treated with staurosporine to induce apoptosis, or with trans-4-carboxy-l-proline (PDC) to induce chronic glutamate excitotoxicity. Furthermore, TDP-43 cytoplasmic inclusions did not co-localize with cleaved caspase-3, suggesting that TDP-43 mislocalization does not generally accompany caspase activation or apoptosis. The induction of TDP-43 cytoplasmic translocation in cerebrocortical slice cultures by tunicamycin provides a platform for further mechanistic investigations of pathological processing of TDP-43.
authors.affiliation: Department of Neurology, The University of Chicago, USA.
authors.forename: Cadman
authors.initials: C
authors.lastname: Leggett
authors.forename: Daniel S
authors.initials: DS
authors.lastname: McGehee
authors.forename: James
authors.initials: J
authors.lastname: Mastrianni
authors.forename: Wenbin
authors.initials: W
authors.lastname: Yang
authors.forename: Tao
authors.initials: T
authors.lastname: Bai
authors.forename: James R
authors.initials: JR
authors.lastname: Brorson
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000633:toxicity; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D002479:Inclusion Bodies / Q000378:metabolism* / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009924:Organ Culture Techniques; D021381:Protein Transport / Q000502:physiology; D057177:TDP-43 Proteinopathies / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D014415:Tunicamycin / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D000900:Anti-Bacterial Agents; D004268:DNA-Binding Proteins; D014415:Tunicamycin