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Updated: Oct 3, 2026

Analysis of SNARE-mediated Membrane Fusion Using an Enzymatic Cell Fusion Assay
09:19

Analysis of SNARE-mediated Membrane Fusion Using an Enzymatic Cell Fusion Assay

Published on: October 19, 2012

CD28 stimulation regulates its association with N-ethylmaleimide-sensitive fusion protein and other proteins involved

M Heller1, J D Watts, R Aebersold

  • 1Department of Molecular Biotechnology, University of Washington, Seattle, WA, USA.

Proteomics
|October 30, 2001
PubMed

Insights

CD28 co-stimulation involves N-ethylmaleimide-sensitive fusion protein (NSF) and vesicular transport proteins. NSF binding to CD28 is crucial for T cell activation, suggesting an NSF-catalyzed mechanism.

Area of Science:

  • Immunology
  • Cell Biology
  • Molecular Biology

Background:

  • CD28 provides a critical co-stimulatory signal for T cell activation.
  • The precise molecular mechanism of CD28 co-stimulation remains largely unknown.

Purpose of the Study:

  • To investigate the molecular players involved in CD28 co-stimulation.
  • To elucidate the mechanism underlying CD28-mediated T cell activation.

Main Methods:

  • Mass spectrometric protein identification was used to analyze CD28 immunoprecipitates.
  • Jurkat T cells were used for protein analysis.
  • N-ethylmaleimide treatment was applied to assess protein interactions.

Main Results:

  • N-ethylmaleimide-sensitive fusion protein (NSF) and proteins involved in vesicular transport were found associated with CD28.
  • This association was dependent on CD28 stimulation.
  • N-ethylmaleimide treatment disrupted the NSF/CD28 interaction and blocked CD28 association with a 103 kDa phosphoprotein.

Conclusions:

  • CD28 co-stimulation may involve an NSF-catalyzed mechanism.
  • Vesicular protein sorting pathways might play a role in CD28 function.

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