Fig. 7. Immunogold electron microscopy showing the subcellular localization of prominin-1 in murine epididymis. Ultrathin cryosections of the apical surface of epithelial cells lining the corpus of the epididymis were incubated with (A) or without (B) E3 antiserum followed by 15-nm Protein-A/gold. Arrows indicate regions of the plasma membrane between the stereocilia; asterisks indicate spermatozoa. Scale bars, 625 nm (A); 640 nm (B).