NOD-dependent chromatin stretching events are associated with two different types of microtubule–chromatin interactions. (A) A whole cell two-color confocal image of a GFP–α-tubulin (green–) and NOD-mCherry (red)–expressing S2 cell with the chromosome shown in B and C highlighted (white box). (B and C) Selected frames from confocal time-lapse imaging of chromatin stretching events. The chromosome is attached to the pole through kinetochore microtubules (bottom left corner, arrow). (B) An example of a chromatin stretching event extending along a microtubule that makes a glancing interaction with the chromosome. The chromatin is stretched toward the plus end before it is retracted coincident with the depolymerizing microtubule. (C) A chromatin stretching event that is associated with a polymerizing microtubule–chromosome interaction. Note that the chromatin stretches along with the polymerizing microtubule before pausing and then rapidly retracting, causing the microtubule to buckle. The separation between the plus end of the microtubule and the stretched chromatin at t = 15 s is a consequence of sequential imaging. (D) A plot of velocity versus time for the two stretch events shown in B and C. The positive values represent extension velocities and the negative values reflect recoil velocities. Closed arrowheads denote the leading edges of stretched chromatin and open arrowheads mark the microtubule plus ends. See Video 5. Bars: (A) 10 µm; (B and C) 1 µm.