Effects of overexpression of GFP-TDP-43, GFP-TDP-43(86-414) or GFP in human H4 cells, in the presence or absence of the EIF2B activator DNL343.

Neuronal TDP-43 aggregates are a hallmark ALS pathology. The integrated stress response (ISR) occurs downstream of TDP-43 pathology and may exacerbate TDP-43 aggregation and neurodegeneration. Here we tested the effects of overexpression of GFP-taggted TDP-43 proteins in H4 cells, in the presence or ascence of the EIF2B activiting small molecule DNL343. Cytoplasmic TDP-43 expression caused upregulation of ISR gene transcripts, including MTHFD2, GDF15, SLC7A11, and ATF3, relative to the GFP expressing sample. Transcript level changes induced by GFP-TDP-43(86-414) were prevented by DNL343 treatment, with significant downregulation of ISR genes, including CHAC1, ATF4, and DDIT3.