a) TDP-43 expression increases eIF2α-phosphorylation levels. Genes were expressed in the nervous system in a drug-inducible manner with the elavGS driver. eIF2α- phosphorylation level of elavGS/UAS-YFP and elavGS, TDP-43/UAS-YFP flies fed as adults on RU486 (40μg/ml), and assessed at the indicated time-points. Genotypes: Control is elavGS/UAS-YFP. TDP-43 is elavGS, UAS-TDP-43(S)/UAS-YFP. Mean ± s.e.m., n=3 independent experiments. *p<0.05, *** p<0.001, n.s., not significant. (Student’s t-test).
b) Altering the levels of genes that reduce stress granule formation mitigates TDP-43 toxicity, and that promote stress granule formation enhances TDP-43 toxicity. Mean ± 95% CI of four experiments. Genotypes: elavGS/UAS-YFP is elavGS/UAS-YFP. elavGS, TDP-43/UAS-YFP is elavGS, UAS-TDP-43(S)/UAS-YFP. elavGS, TDP-43/Gadd34 RNAi is elavGS, UAS-TDP-43(S)/UAS-Gadd34. RNAiHMS00811. elavGS, TDP-43/Rox8 RNAi is elavGS, UAS-TDP-43(S)/UAS-Rox8. RNAiHMS00472. elavGS, TDP-43/PEK RNAi is elavGS, UAS-TDP-43(S)/UAS-PEK. RNAiGL00030. All flies raised with RU486 (40μg/ml) (125 flies per genotype). ANOVA for significance, followed by Tukey’s multiple comparison test, **p<0.01, *** p<0.001, # p<0.0001, n.s., not significant.
c) eIF2α-phosphorylation level of elavGS, TDP-43/UAS-YFP, elavGS, TDP-43/Rox8 RNAi, elavGS, TDP-43/Gadd34 RNAi and elavGS, TDP-43/PEK RNAi. Mean ± s.e.m., n=3 independent experiments. *p<0.05, n.s., not significant (Student’s t-test).
d) Total, nuclear and cytosolic TDP-43 protein level in 10d fly heads. Genes predicted to increase stress granules formation increase cytoplasmic TDP-43 protein levels. Mean ± s.e.m., n=3 independent experiments. *** p<0.001, n.s., not significant (Student’s t-test).