(A) Lysates were prepared from selective human cell lines and processed for quantitative immunoblot using antibody GTX634482 (HEK, human embryonic kidney; HeLa, human cervical cancer; U2OS, human osteocarcoma; RKO, human colon carcinoma; U87/U251, human glioblastoma; NPC, human neural precursor cells; MN, human motor neurons). The total protein stained transfers are shown as a loading control. The C9ORF72 protein signal as a ratio to total protein was determined, normalized to parental HEK-293 cells (red), and presented as fold change (blue numbers). (B) Cell lysates of parental and KO U2OS cells were analyzed by immunoblot with C9ORF72 antibody GTX634482. (C) Mosaic strategy used to investigate antibody specificity by immunofluorescence.