HSP70 interacts with eIF4G in vitro. (A,B) Cell lysates were analyzed with a Western blot to detect the protein level by using primary antibodies targeting eIF4A, eIF4E, eIF4G, 4EBP1, and HSP70. β-actin was used as an internal control. (C) Flag-HSP70 immunoprecipitated eIF4G from the cell lysates of HepG2 and Huh7 cells transfected with or without Flag-HSP70 plasmid. Immunoprecipitates were analyzed with Flag or eIF4G antibodies via Western blot. (D) The HSP70-eIF4G interaction was detected by in situ PLA. Flag-HSP70 transfected cells and control cells were incubated with mouse anti-HSP70 mAb and rabbit anti-eIF4G mAb. Red signal spots are shown to indicate the protein interaction between HSP70 and eIF4G. Magnification 20×; Scale bar 50 μm. Quantitative data from three experiments with similar results were analyzed. Data are presented as mean ± standard deviation (SD). * p < 0.05, ** p < 0.01, *** p < 0.001 compared with corresponding control groups.