FIG. 5.

KUN-induced CM and PC structures are labelled with a marker associated with the IC. Infected cells were harvested and processed for cryo-IEM and immunolabelling. (A to D) Ultrathin cryosections were cut and probed with antibodies to the IC marker ERGIC53 and labelled with protein A–10-nm-diameter gold particles. Both PC and CM were randomly but specifically labelled in panels A and B, respectively; they appear to be interconvertible structures (see text), and hence their labelling as either CM or PC is sometimes subjective. The arrows in panels C and D indicate small cytoplasmic vesicles (possibly elements of the IC) labelled with anti-ERGIC53 antibodies in close proximity to virus-induced CM also labelled with anti-ERGIC53 antibodies. (E and F) Cryosections were dual labelled with antibodies to ERGIC53 (15-nm-diameter gold) and NS3 (10-nm-diameter gold), and coincidental labelling of both antibodies within CM is highlighted with arrowheads. V, accumulated virus particles within distended ER (C). Bars, 200 nm.