Two types of chromatin stretch events occur in NOD-mCherry–expressing cells. (A) Plot of distance versus time (5-s intervals) for 21 separate chromatin stretching events. Persistent stretch events are highlighted in blue. (B) NOD-mCherry stretches contain phospho-H3 (Serine 10)–positive chromatin. NOD is red and phospho-H3 is green in the merged image. (C) The mean extension velocities of rapid and persistent stretch events. (D) Chromatin in rapid events extends at ∼10 µm/min, whereas extension in persistent events starts at ∼8 µm/min and slows over time to ∼2 µm/min. (E and F) Kymographs of rapid and persistent stretch events imaged by spinning disk confocal microscopy with high temporal resolution (1.5–2-s intervals). Whole cell images are shown below each kymograph highlighting the stretch event that is represented in the kymograph. In the first image, the open arrowhead marks the periphery of the chromosome and the solid arrow marks the edge of the stretch event. Stretches are highlighted in subsequent images with solid arrows. (E) Rapid events exhibit rapid and uniform extension and recoil velocities. (F) Persistent stretch events exhibit variable extension and recoil velocities over time. Bars show standard deviation. Bars: (B, top; and E and F, bottom) 5 µm; (B, bottom) 2.5 µm; (E and F, top) 1 µm (horizontal) and 10 s (vertical).