Fig. 3. Inhibitors of COPI and COPII do not affect peroxisome morphology. Normal human fibroblasts were incubated either in the absence (A,B) or in the presence (C,D) of 2 µg ml^-1 BFA. After 20 hours, cells were fixed and stained with antibodies to acyl-CoA-oxidase (A,C) or giantin (B,D). NH-tagged Sar1p(H79G) DNA was microinjected into the nucleus of normal human fibroblasts. After 20 hours, cells were processed for double indirect immunofluorescence with antibodies to catalase (E) and the NH epitope (F), or with antibodies to ERGIC53 (G) and the NH epitope (H).