Fig. 6. The effect of siRNA-mediated knockdown of POLG in undifferentiated CCE/R mESCs. Pooled cell lysates were prepared from FACS non-transfected and siRNA-transfected CCE/R. Equal amounts of protein (100 µg) were electrophoresed on a 9% SDS-PAGE gel then semi-dry blotted onto a polyvinyl difluoride membrane. The membrane was probed for β-actin, POLG, OCT4 and brachyury with the membrane being stripped between each probing. Lane 1, non-transfected undifferentiated CCE/R mESCs; lane 2, undifferentiated CCE/R mESCs transfected with negative control siRNA (75 nM); lane 3, undifferentiated CCE/R mESCs transfected with siRNA targeting POLG (75 nM); lane 4, human embryonic kidney cells; lane 5, mouse embryonic fibroblasts.