Fig. 7. Endosome-to-Golgi transport of STxB is inhibited by tGolgin-1 depletion. HeLa cells that were untreated (Ctl.), transduced with siRNA-1 or treated for 2 hours with nocodazole (Noc.) were incubated with Alexa-488-conjugated STxB on ice for 45 minutes, washed and then warmed to 37°C for 60 minutes. Cells were then fixed, labelled with antibodies to GM130 and RRX-conjugated anti-mouse immunoglobulin (A-I) or to TGN46 and Lamp1 followed by AMCA- and RRX-conjugated secondary antibodies (J-O), and analysed by fluorescence microscopy. siRNA-1-transduced cells were identified based on the dispersed staining pattern for TGN46. Panels show single staining for STxB (A,D,G,J,M), GM130 (B,E,H) or Lamp1 (K,N), or overlays of the two labels, as indicated (C,F,I,L,O). Boxed images were magnified two-fold in the top right corner in C,F,I,O to emphasize the degree of colocalization.