Fig. 6: The condensation and cytotoxicity of TDP-43 CTFs that carry hydrophobic region-lacking GRR in Neuro2a cells.

a Domain structure and abbreviation of Homo sapiens TDP-43, Caenorhabditis elegans orthologue of TDP-43 (TDP-1), and its CTFs: amino acid 220-414 (C220), 220-262 (F220), C220 lacking 311-340 region (C220Δ), and a fusion protein of F220 and C-terminal region (C-term) of TDP-1 (F220c). b Confocal fluorescence and bright field microscopic images of Neuro2a cells expressing GFP-tagged C220Δ and F220c. Cells containing cytoplasmic condensates (bottom) or not containing them (top) were represented. Bars = 5 μm. c The population of Neuro2a cells containing condensates (conds) in the cytoplasm. Mo denotes GFP monomers. Bars: mean and 95% CI; Dots: raw values (n = 4 independent experiments). d Left: Western blot of 1% SDS-soluble (S) and -insoluble (P) cell lysates using an anti-GFP and anti-α-tubulin antibody. The right values (25, 37, and 50 kDa) represent the positions of the molecular weight marker. Right: The quantification of the abundance of TDP-43 CTFs in the insoluble fraction (Insol.). The abundance shows the normalized band intensity in the P fraction to total (S + P) fraction (n = 3 independent experiments) (right). e The proportion of dead cells expressing GFP-tagged C220, F220, C220Δ, and F220c. In C and D, Bars: mean and 95% CI; Dots: raw values (n = 4 independent experiments); ND: Not determined; p-values above the lines: one-way ANOVA with Tukey’s test.