Fig. 7

SDPR stabilizes PTRF secretion via exosomes and does not impede the effect of UBE2O. A Flag-PTRF and UBE2O-Myc were overexpressed in HeLa cells. Then, Flag-PTRF in the cell lysates was immunoprecipitated with Flag M2 beads. Flag-PTRF associated endogenous SDPR in HeLa cells was immunoblotted by western blot. B Flag-SDPR and UBE2O-Myc were co-transfected into HeLa cells. Flag-SDPR in the cell lysates was immunoprecipitated with Flag M2 beads. The immunoprecipitates and the total cell lysates were immunoblotted for the indicated antibodies. C, D UBE2O-Myc was transiently transfected into Flag-PTRF stable HeLa cell line or Flag-SDPR stable HeLa cell line. Serum-free culture medium which had culture HeLa cell lines for 40 h was collected to isolate exosomes. Then, exosomes were identified by transmission electron microscopy (C). Cell lysates and exosomes were analyzed by western blot as indicated (D)