DYN-1 function is required during a late stage of cytokinesis. (A) Representative still images taken of a single embryo show accumulation of dynamin at the intercellular bridge (arrowheads) by fluorescence light microscopy. (B) Quantification of dynamin accumulation after onset of furrow initiation. Error bars show SD. r.u., relative units. n = 10. (C) Representative still fluorescence images of a dyn-1(RNAi) embryo during the late stages of cytokinesis. The membrane is shown in green (GFP::PH) and the microtubules in red (mCherry::β-tubulin). Cleavage furrow regression is indicated (arrowhead). n = 5. (D) Representative still images of a dyn-1(RNAi) embryo showing the start of furrow regression adjacent to the midbody (arrowheads). n = 5. (E) Electron tomography of a dyn-1(RNAi) embryo. The ultrastructure of the intercellular bridge is illustrated in a tomographic slice (left). The corresponding 3D model (middle) and an enlarged region (right) shows an accumulation of nascent vesicles on the plasma membrane (arrowheads). 515 is the time point at which the embryo was frozen and imaged. Bars: (A, C, and D) 10 µm; (E, left and middle) 500 nm; (E, right) 200 nm.