HSP47 accumulates in ER-related vesicles in OI-mutant cells. Immunofluorescence of HSP47 (red) and cell compartments (green): PDI for ER (A–C), Golgin97 for Golgi apparatus (D–F) and ERGIC53 for ER–Golgi intermediate compartment (G–I). Control (A, D and G), HSP47M237T M237T (B, E and H) and FKBP10−/− cells (C, F and I). White arrows identify vesicles accumulating HSP47. Bars represent 10 µm.