Organelles are captured at the proplatelet tip. (A-C) A representative example of mitochondria capture at the proplatelet ends. The mitochondria were labeled with MitoTracker Green, and movements were recorded using fluorescence time-lapse microscopy (See Movie 4). (A) Fluorescence and (B) differential-interference-contrast micrographs. Scale bar, 5 μm. (C) Images of the proplatelet tip (from boxed region in panel A) taken every 5 minutes are shown (See Movie 4). The arrows mark mitochondria that translocate into the proplatelet tip but do not exit. Scale bar, 3 μm. (D) Bar graph comparing the entry and exit of organelles/granules (an equal percentage of mitochondria, α-granules, and dense granules) into and out of proplatelet tips and swellings of proplatelets.