Figure 1.

Effect of RA on the distribution of M6P/IGF2R in neonatal-rat fibroblasts. (A and a) Intracellular localization of M6P/IGF2R in nontreated fibroblasts was detected by immunofluorescence with anti-M6P/IGF2R antibodies. The receptor was concentrated primarily in the perinuclear structure (probably the TGN area). (B and b) Distribution of M6P/IGF2R in RA-treated cells. After treatment with RA (1 μM for 3 h), the receptor translocated from the perinuclear area to cytoplasmic vesicles (possibly the endosomes and lysosomes). (Bars for A and B = 20 μm; bars for a and b = 4 μm.)