parasomal sacs

Description:

Cell sectioned perpendicular to the surface. The parasomal sac ends internally as a coated pit (cop), coated with clathrin. Where the coated pit has pinched off a clathrin-coated vesicle (cov) is formed. When the clathrin is removed an endosome (e) results. Other clathrin-coated vesicles (arrow) arise from early endosomes. kd, kinetodesmal fibers in cross section; il, infraciliary lattice fiber. Collidine-buffered fixative. EM taken on 5/21/70 by R. Allen with Hitachi HU11A TEM. Neg. 27,750X. Bar = 0.2 microns. Partly published in J. Cell Sci. 101:449-461, 1992. This image is available in Richard Allen's collection.