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Caspase 7-induced cleavage of kinectin in apoptotic cells

T Machleidt1, P Geller, R Schwandner

  • 1Institute of Immunology, Christian-Albrechts University of Kiel, Germany.

FEBS Letters
|October 15, 1998
PubMed

Insights

Kinectin, a receptor for kinesin, is cleaved during apoptosis. Caspase 7 mediates this proteolysis, generating a 120-kDa fragment from the 160-kDa kinectin form in response to various apoptotic signals.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Kinectin is identified as the primary receptor for kinesin, a motor protein essential for intracellular transport via microtubules and membrane trafficking.
  • Apoptosis, or programmed cell death, involves a cascade of enzymatic reactions, including proteolysis by caspases.

Purpose of the Study:

  • To investigate the role of kinectin during apoptosis.
  • To identify if kinectin is a substrate for caspase-mediated proteolysis.
  • To determine the specific caspase responsible for kinectin cleavage.

Main Methods:

  • Treatment of cultured cells with various apoptotic stimuli (TNF, anti-Fas, anticancer drugs, gamma-radiation, ceramide).
  • Analysis of protein cleavage using Western blotting or similar techniques to detect changes in kinectin molecular weight.
  • In vitro assays or cell-based experiments to confirm the involvement of specific caspases.

Main Results:

  • Diverse apoptotic stimuli induce rapid proteolytic cleavage of the 160-kDa kinectin.
  • Cleavage results in the formation of a distinct 120-kDa kinectin fragment.
  • Evidence strongly implicates caspase 7 as the enzyme responsible for kinectin proteolysis.

Conclusions:

  • Kinectin is a novel target for caspase-mediated proteolysis during the apoptotic process.
  • Caspase 7 directly cleaves kinectin, contributing to cellular events during apoptosis.
  • This finding reveals a new molecular mechanism linking membrane trafficking regulation to programmed cell death.

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