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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

Tyrosine kinase activation provides an early and requisite signal for Fas-induced apoptosis

C M Eischen1, C J Dick, P J Leibson

  • 1Department of Immunology, Mayo Clinic, Rochester, MN 55905.

Journal of Immunology (Baltimore, Md. : 1950)
|September 1, 1994
PubMed

Insights

Fas Ag ligation triggers rapid protein tyrosine phosphorylation, a key early step in programmed cell death (apoptosis). Inhibiting protein tyrosine kinases blocks this cell death, highlighting their essential role in Fas-mediated apoptosis.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Selective cell death is crucial for immune system development and eliminating foreign antigen-expressing cells.
  • Fas Ag (antigen)-induced apoptosis, a form of programmed cell death, contributes to these processes.
  • The precise molecular mechanisms and second messengers mediating Fas-induced apoptosis remain incompletely understood.

Purpose of the Study:

  • To investigate the signal transduction pathways initiated by Fas Ag ligation.
  • To identify the early molecular events and second messengers involved in Fas-induced apoptosis.

Main Methods:

  • Evaluation of Fas-initiated signal transduction in susceptible cell types.
  • Analysis of protein tyrosine phosphorylation following Fas ligation.
  • Assessment of in vitro protein kinase activity.
  • Use of pharmacologic inhibitors of protein tyrosine kinases.

Main Results:

  • Fas ligation rapidly induces tyrosine phosphorylation of multiple cellular proteins within 1 minute.
  • Increased in vitro protein kinase activity of tyrosine-phosphorylated proteins was observed.
  • Pharmacologic inhibition of protein tyrosine kinases blocked Fas-induced DNA fragmentation and prolonged cell survival in a dose-dependent manner.

Conclusions:

  • Protein tyrosine kinase activation is an early and essential signal in Fas-induced apoptosis.
  • These findings elucidate a critical step in the Fas-mediated programmed cell death pathway.
  • Targeting protein tyrosine kinases may offer therapeutic strategies for modulating apoptosis.

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