(A) C9ORF72 iPSN cells contain cytoplasmic GGGGCC RNA foci, while control iPSNs do not.
(B) Quantification of cytoplasmic RNA foci reveals that cytoplasmic foci are RNase A sensitive.
(C) Single-optical plane (∼0.3 µm) image of C9ORF72 ALS motor cortex also shows cytoplasmic GGGGCC RNA foci similar to iPSNs.
(D) RAN protein shown by IF using C9RANT antibody that preferentially detects the poly-(Gly-Pro) RAN product in C9ORF72 iPSNs but not control iPSNs.
***p < 0.001. Scale bar = 5µm for (A), (D), and (E), right panels; 1 mm for (C), and 20 µm for (D) and (E), left panels. See also Figure S3B.