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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

A pre-existing protease is a common effector of thymocyte apoptosis mediated by diverse stimuli

H O Fearnhead1, A J Rivett, D Dinsdale

  • 1MRC Toxicology Unit, University of Leicester, UK.

FEBS Letters
|January 9, 1995
PubMed

Insights

Proteolysis inhibitors impact apoptosis differently. N-tosyl-L-lysyl chloromethylketone (TLCK) halts apoptosis early, suggesting a pre-existing trypsin-like protease is key to cell death.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Proteolysis plays a role in apoptotic cell death.
  • Specific protease inhibitors have varying effects on apoptosis.

Purpose of the Study:

  • To investigate the differential effects of TLCK and TPCK on apoptosis in immature rat thymocytes.
  • To identify the specific protease targeted by TLCK during apoptosis.

Main Methods:

  • Treatment of immature rat thymocytes with TLCK and TPCK.
  • Observation of apoptosis induction and DNA fragmentation.
  • Analysis of protease activity and synthesis.

Main Results:

  • TLCK significantly inhibits apoptosis induced by various stimuli at an early stage.
  • TPCK shows different effects compared to TLCK.
  • The TLCK-sensitive target is pre-existing, not newly synthesized.

Conclusions:

  • A trypsin-like protease, sensitive to TLCK, is a crucial effector in thymocyte apoptosis.
  • Differential inhibition by TLCK and TPCK supports the role of this specific protease.

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