Localization of Juno and CD9 defines three segments of the cell surface. (A) Immunofluorescence of Juno and CD9. Single confocal section (single slice) and maximum-intensity Z projection (Z-projection) are shown. These membrane proteins form discrete structures and exhibit polarized localization patterns. The lower panel shows high-magnification images of DA (dense Juno/CD9 area), FA (fewer Juno/CD9 area), and NA (no Juno/CD9 area). The zona pellucida was removed (A–C). (B) Average angle between the borders and maternal chromosomes. The angles from three different positions on the border for each egg were averaged. (C) Superresolution image of Juno and CD9 by Airyscan detector. There are at least two populations: one contains Juno only (circles), and the other contains both Juno and CD9. In structures containing both Juno and CD9, the intensity peaks of Juno and CD9 are not always matched (arrows).