Fig. 3

Structural model of the special ciliary structure. A,B,C SEM images of three cumulus granulosa cells (cGCs) with characteristic cilia at transverse sections (a,b) and longitudinal section (c). D,E,F Reconstructed ciliary structures in their corresponding cGCs. G,H,I 3D model to show spatial relationship of cilia in cGCs with color transparency. J Magnified image of the transverse section of the distal cilium showing the absence of 9 + 2 structure. K Magnified image of the longitudinal structure of the distal cilium showing basal body at its root (red box). L Reconstructed model to show the different orientation of cilia in cGCs around the oocyte. M Horizontal schematic displaying the spatial position and directions of the cilia of four cGCs