MVBs release intraluminal vesicles at the cytokinetic furrow.

(A) Fluorescence maximum projection image capturing dividing cells from a dissected Drosophila cyst. Green, eYFP-Rab7; red, mRFP-Anillin. Inset, vesicles adjacent to a cleavage furrow. Scale bar: 10 μm. (B) Corresponding TEM section. Endosomes adjacent to the cleavage furrow are boxed. Scale bar: 10 μm. (C) Higher magnification TEM image of area boxed in B. Scale bar: 500 nm. Arrows indicate discontinuity in outer membranes of MVBs. (D) Subsequent TEM section of same area, showing make-up of vesicles at high magnification. Scale bar: 300 nm. (E) A model depicting endocytosis of CPE from plasma membrane, the maturation of these endosomes into multivesicular bodies, targeting and release of intraluminal vesicles at the cleavage furrow. CPE, ceramide phosphoethanolamine; MVB, multivesicular body.