High spatial and temporal resolution imaging reveals that NOD-mCherry associates with the ends of polymerizing microtubules. (A) Selected frame (top) and maximum projection of 50 frames (bottom) from a confocal time lapse of an EB1-GFP (green)– and NOD-mCherry (red)–expressing S2 cell. See Video 6. (B–D) Kymographs of NOD-mCherry and EB1-GFP. (B and C) The extension phases of two rapid stretch events that colocalize with EB1-GFP comets are shown. The kymograph in C is from Video 7. (D) A NOD-mCherry spot that is propelled through the cytoplasm colocalizes with an EB1-GFP comet. See Video 8. (E–G) NOD-mCherry tracks on dynamic microtubules. See Video 9. (E) Selected frame from a confocal time lapse of a GFP–α-tubulin (green)– and NOD-mCherry (red)–expressing mitotic S2 cell showing a NOD-mCherry fragment localized at the microtubule plus end. The fragment is considerably smaller than the syntelically attached chromosome 4 located below it. (F) Line scan of the highlighted region shown in E. (G) Kymographs of NOD-mCherry and GFP–α-tubulin during a tracking event. NOD-mCherry (red) tracks the growing, shortening, and paused plus end of the microtubule (green). Bars: (A and E) 10 µm; (B–D and G) 1 µm (horizontal) and 10 s (vertical).