Fig. 5. CV1 cells overexpressing full-length human MK with an artificial PTS1 signal (SKL) were labelled with antibodies as described in Materials and Methods. Cells were double labelled using antibodies directed against MK (A) and a peroxisomal marker CAT (B). The overlay image of both signals (C) shows a clear colocalisation of MK and CAT in the majority of peroxisomes. In addition, cytosolic labelling of MK can be observed (upper left corner).