Movie 1

Movie 1 shows the time-lapse recording from which snapshots shown in Fig. 2B were taken. Time-lapse recording was made with using a 10x objective with a confocal aperture of 2.0 (z-plane depth of 21.2 μm). The total recording time was 70h showing and images were taken every 21 min. The movie shows a resorbing osteoclast making a trench that is successively caught up by at least two osteoblast-lineage cells. The trench-making osteoclast can be recognized by the crescent shaped actin ring at the leading edge and is marked with a white arrow. The osteoblast-lineage cells can be recognized by the presence of stress fibers and are marked by white and blue arrows. These arrows move just prior to the migration of osteoblast-lineage cells towards the osteoclast. The bone surface is labeled with rhodamine and cells are labeled with SiR actin (stains f-actin)