Fig. 4

a Immunoblotting for FPGS in different cell lines (scramble control and shFPGS#3) with or without exposure to 1 mM NaBu for 72 h. α-Tubulin was used as the internal control. b Immunofluorescence to identify polyglutamylation in TL-1 control and TL-1-shFPGS cells. Scale bar, 50 μm. c Cells were treated with MTX for 24 h, followed by the addition of LV and culturing for another 24 h. Cell viability assay was performed 48 h later. Error bars represent SDs. Viability of cells treated with MTX and MTX + LV as compared with that of control cells (no treatment). *p < 0.01. ns, not statistically significant. d Immunoblotting for DHFR in different cell lines (scramble control and shFPGS#3). α-Tubulin was used as the internal control