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Interactive Molecular Model Assembly with 3D Printing
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Interactive Molecular Model Assembly with 3D Printing

Published on: August 13, 2020

Conformational model

Ruth M Risueño1, Angel R Ortiz, Balbino Alarcón

  • 1Centro de Biología Molecular Severo Ochoa, CSIC-Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain.

Advances in Experimental Medicine and Biology
|December 11, 2008
PubMed

Insights

Conformational changes in T-cell receptor (TCR) cytoplasmic tails, not just ligand-binding regions, are crucial for T-cell activation. This signaling mechanism is vital for immune responses.

Area of Science:

  • Immunology
  • Molecular Biology
  • Structural Biology

Background:

  • Conformational changes in T-cell receptor (TCR) ectodomains beyond ligand-binding loops have been overlooked as a signal transduction mechanism.
  • Biochemical and spectroscopic data indicate that cytoplasmic tails of TCR and B-cell antigen receptor (BCR) undergo conformational changes upon stimulation.

Purpose of the Study:

  • To investigate the transmission of conformational changes from TCR ectodomains to cytoplasmic tails upon ligand binding.
  • To explore the role of these conformational changes in T-cell and B-cell activation.

Main Methods:

  • Biochemical assays
  • Spectroscopic analysis
  • Functional assays linking conformational changes to T-cell activation

Main Results:

  • Evidence suggests conformational changes occur in TCR and BCR cytoplasmic tails, not solely in ectodomains.
  • Ligand binding to TCR ectodomains likely triggers a transmission of conformational changes to the cytoplasmic tails via CD3 subunits.
  • Functional correlates link these conformational changes to full T-cell activation.

Conclusions:

  • Conformational changes in the entire TCR complex, including cytoplasmic tails, are critical for signal transduction.
  • Understanding the mechanism of transmission and the role of these changes is essential for elucidating T- and B-cell activation pathways.

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