Function of the FLJ20420 gene. (A–B) The subcellular localization of FLJ20420 protein.

<p>(A) Cells were transiently transfected with pEF1-HisC-FLJ20420 for 48 h, fixed with 4% paraformaldehyde, and analyzed by immunofluorescence. Monoclonal anti-Xpress^TM antibody (Invitrogen, CA), at a dilution of 1∶500, was used to detect the FLJ20420 fusion protein (green). Phalloidin (Sigma), at a dilution of 1∶500, was used to stain the cell skeleton (red). DAPI (Sigma), at a dilution of 1∶5000, was used to stain cell nuclei (blue). FLJ20420 protein expression is apparent in both the cytoplasm and nuclei of HeLa cells and NIH/3T3 cells. (B) A549 cells were detected by immunofluorescence with monoclonal anti-FLJ20420 antibody at a dilution of 1∶1000 to detect the FLJ20420 native protein (green). DAPI (Sigma), at a dilution of 1∶5000, was used to stain cell nuclei (blue). FLJ20420 protein expression is apparent in both the cytoplasm and nuclei of A549 cells, but most in the cytoplasm. (C) Cell cycle analysis was evaluated by FACS after using PI to stain the cellular DNA. (D) Cell viability assay: 2×10⁵ cells/well were seeded in 6-well plates and transfected with specific or control siRNA. After incubation for 48 h, cell viability was determined by the MTT assay. (E) Cells transfected with FLJ20420 siRNA were treated with cisplatin (0, 0.625, 1.25, 2.5, 5, 10, 20, or 40 µg/ml) for 24 h and then analyzed by the MTT assay. (F) Cells transfected with FLJ20420 siRNA were treated with cisplatin (5 µg/ml) for 24 h and then analyzed for apoptosis by FACS.