Figure 3.

The postmitotic midbody regulates cell proliferation. The extracellular, membrane-bound postmitotic midbody is recognized by engulfing cells via a PS/MFGE8/integrin complex. Rac1-dependent actin polymerization is required for postmitotic midbody internalization (top). Once internalized, the postmitotic midbody now exists as a double-membrane structure termed the MBsome (bottom). It facilitates EGFR- and FAK-dependent signaling to modulate cell proliferation and anchorage-independent growth and is ultimately degraded. It is unknown if the contents of these internalized postmitotic midbodies ever reach the cytosol of the cell. Please note that this schematic representation of MBsomes was modified from the figure published in Peterman et al. (2019).