Figure 4.

Optineurin and Nucleocytoplasmic Transport Factors Are Recruited into Mutant FUS Assemblies

(A) Optineurin is a component of poly(I:C)-induced SGs in WT cells. Cells were analyzed 6 h post-transfection.

(B) More optineurin is retained in poly(I:C)-induced SGs in FUSΔNLS lines compared with WT cells. Arrowheads indicate optineurin-positive SGs in WT cells. Cells were analyzed 24 h post-transfection. Graph shows optineurin staining intensity in SGs (n ≥ 30). ^∗∗∗p < 0.001, ^∗∗∗∗p < 0.0001 (one-way ANOVA with Dunnett’s test). Data are represented as mean ± SEM.

(C) FAs formed by overexpressed GFP-tagged FUS R522G sequester optineurin under basal conditions.

(D) Nucleocytoplasmic transport factors Nup107, KPNA2, and TNPO1 are recruited into mutant FUS cytoplasmic assemblies in poly(I:C)-stimulated FUSΔNLS cells. The ΔNLS11_het cell line contains endoFGs and therefore forms FAs but not SGs. Cells were analyzed 6 h post-transfection.

Scale bars, 10 μm.