Figure 2: Generation of murine Fubp1 KO ESC clones. (a) To knockout Fubp1 in murine ESCs, two gRNA sequences were cloned into the CRISPR/Cas9 plasmid pLCVv2, and one nontarget control (NTC) gRNA was cloned as a control. (b, c) FUBP1-deficient ESC clones were identified by western blot analysis (b) and by anti-FUBP1 immunohistochemistry (c) of undifferentiated cells. The weak brownish color of single Fubp1 knockout cells shown in (c) is most likely due to imperfect washing-off of unbound antibody from parts of the slides with high cell density. Scale bars represent 200 μm.