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An Apoptotic 'Eat Me' Signal: Phosphatidylserine Exposure

Katsumori Segawa1, Shigekazu Nagata1

  • 1Laboratory of Biochemistry and Immunology, WPI Immunology Frontier Research Center, Osaka University, 3-1 Yamada-oka, Suita 565-0871, Japan.

Trends in Cell Biology
|October 7, 2015
PubMed

Insights

Cellular

Area of Science:

  • Cell Biology
  • Biochemistry

Background:

  • Apoptosis is crucial for development and homeostasis.
  • Clearance of apoptotic cells requires 'eat me' signals, like phosphatidylserine (PtdSer) exposure.
  • PtdSer is normally on the inner cell membrane but flips to the outer surface during apoptosis.

Purpose of the Study:

  • To discuss recent findings on the molecular mechanisms of apoptotic PtdSer exposure.
  • To review the mechanisms of apoptotic cell clearance.

Main Methods:

  • Identification of phospholipid flippase and scramblase molecules.
  • Discussion of molecular mechanisms regulating PtdSer exposure.

Main Results:

  • The molecules responsible for phospholipid flipping and scrambling have been identified.
  • Apoptosis triggers scramblase activation, leading to PtdSer externalization.

Conclusions:

  • Understanding PtdSer exposure mechanisms is key to apoptotic cell clearance.
  • Recent discoveries illuminate the molecular basis of PtdSer exposure and cell engulfment.
Keywords:
apoptosisflippasephagocytosisphosphatidylserinescramblase

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