Figure 6.

Freeze fracture revealed the anatomical compartmentalization of GJIC around the onset of hearing. a–c, P8 organ of Corti. a, Survey view of fracture across the pillar cell region revealing an inner pillar cell (IPC) adjacent to an outer pillar cell (OPC). Boxes indicate areas shown at higher power in b and c. b, Membrane faces of adjacent inner pillar cell and outer pillar cell show numerous gap junction plaques (arrows) down the membranes all along the regions of contact between the two cells. c, Membrane face of inner pillar cell adjacent to inner phalangeal cell; numerous gap junction plaques (arrows) are exposed. d–f, P12 organ of Corti. d, Region in which the head of an outer pillar cell abuts below the heads of two adjacent inner pillar cells. IHC, Inner hair cell. Boxes enclose areas shown at higher power in e and f. e, Membrane faces in which outer pillar cells meet the heads of inner pillar cells. Gap junction plaques cannot be identified on the membrane faces in which the two cell types meet. f, Membrane face of the outer pillar cell in which it is adjacent to the next outer pillar cell. Gap junction plaques (arrows) are present. Scale bars: a, d, 2 μm; b, c, e, f, 0.5 μm.