HCV NS3/4A colocalizes with Cardif at mitochondrial membrane. The localization of HCV proteins and Cardif was studied in Huh7 cells. The cells were transfected with HCV protein expression constructs (NS3/4A, core or NS5A) and 48 h later cells were fixed and stained. The colocalization was visualised by confocal microscopy. Cells were stained for Cardif (endogenous) (A, D, G, J), mitochondria with Mitotracker Red 580 (B), NS3/4A (E), core (H) and NS5A (K) and the signals were merged (C, F, I, L).