Phagocytosis of an apoptotic cell
Time-lapse movies depicting the engulfment and degradation of an apoptotic cell in an embryo of the nematode Caenorhabditis elegans
In this wild-type embryo, the plasma membrane of an engulfing cell is labeled with CED-1, a phagocytic receptor that recognizes neighboring apoptotic cells and clusters around them, tagged by the green fluorescence protein (GFP) (left panel). The engulfment process occurs when the engulfing cell extends pseudopods (labeled with CED-1::GFP) towards and then around an apoptotic cell. Engulfment is considered complete when pseudopods from both sides fuse with each other, creating a phagosome that contains the apoptotic cell. After engulfment is complete, a monomeric red fluorescence protein (mRFP) tagged marker (2xFYVE::mRFP1) for phosphatidylinositol 3-phosphate (PI(3)P) is enriched on the surface of the phagosome and persists there (right panel). The phagosome gradually decreases in volume and finally disappears after 76 min, indicating the complete degradation of the apoptotic cell inside.
See news release for detail. Images captured and assembled by Nan Lu, using the DeltaVision Deconvolution Microscope.