Extended Data Fig. 4: TDP-43, actin binding proteins, and BAG3 are enriched in the insoluble fractions after cell exposure to proteotoxic stress.

(a) Schematic diagram illustrating the biochemical analysis of soluble and insoluble fractions of cells expressing TDP-43∆NTD-Clover or Clover. (b) Analysis of the levels of TDP-43∆NTD-Clover, endogenous TDP-43, FLNA, β-Actin, Actinin, BAG3, HSPA1A, GAPDH in the soluble fractions of cells under no stress, 100 µM NaAsO2 or 10 µM MG132 treatment. Data are from three biological replicates. (c) Analysis of the levels of TDP-43∆NTD-Clover, endogenous TDP-43, FLNA, β-Actin, Actinin, BAG3, HSPA1A, GAPDH in the insoluble fractions of cells under no stress, 100 µM NaAsO2 or 10 µM MG132 treatment. Data are from three biological replicates. (d) Quantification of the levels of TDP-43∆NTD-Clover, endogenous TDP-43 and FLNA in both soluble and insoluble fractions. n = 3 independent replicates. Error bar: SD. (e) Specific interaction of TDP-43 with FLNA and actin under NaAsO2 or MG132 stress conditions detected by immunoprecipitation.