Fig. 6. EM immuno-gold localization of PtNSF in gene-silenced (A,B,D) and control cells (C) using peptide-specific Abs against PtNSF. Note the irregular distribution of label in the cytoplasmic zones enriched in endoplasmic reticulum (er) (A,B,D), in contrast to the control (C) with rather homogenously distributed gold grains in the cytoplasm. In all cases (A-D), mitochondria (m), trichocysts (t), alveolar sacs (as) and ciliary basal bodies (bb) are essentially devoid of label. In A and B, silencing has produced the accumulation of densely labeled vesicle aggregates (va), whose morphology is more clearly identified, probably as clusters of branching ER, in panel D, which shows a higher magnification of the area marked in the lower right corner of B. Some label also occurs in bona fide lysosomes (l). Bars, 0.1 µm.