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A coiled-coil structure of the alphaIIbbeta3 integrin transmembrane and cytoplasmic domains in its resting state

Kay-Eberhard Gottschalk1

  • 1Department of Biological Chemistry, The Weizmann Institute of Science, Herzl St. 1, 76100 Rehovot, Israel. kay.gottschalk@physik.uni-muenchen.de

Structure (London, England : 1993)
|May 17, 2005
PubMed

Insights

Researchers modeled the resting state structure of alphaIIbbeta3 integrin transmembrane domains. This coiled-coil structure, involving a Glycophorin A-like motif, explains integrin signaling mechanisms.

Area of Science:

  • Structural biology
  • Cell signaling
  • Biochemistry

Background:

  • Integrin receptors mediate bidirectional cell signaling.
  • Transmembrane integrin domains are crucial for these signaling events.
  • Understanding integrin structure is key to deciphering signaling mechanisms.

Purpose of the Study:

  • To generate a structural model of the transmembrane and cytosolic domains of alphaIIbbeta3 integrin in its resting state.
  • To provide structural insights into integrin signaling.
  • To propose a mechanism for integrin signal transduction.

Main Methods:

  • Computational restrained conformational search of helix-helix interactions.
  • Integration of existing NMR structural data.
  • Analysis of conserved sequence motifs, including Glycophorin A (GpA)-like sequences.

Main Results:

  • A structural model of the alphaIIbbeta3 integrin resting state was developed.
  • The model reveals an intricate coiled-coil structure for the transmembrane domains.
  • The Glycophorin A (GpA)-like sequence motif in the alpha subunit is positioned at the interface.

Conclusions:

  • The proposed coiled-coil structure provides a structural basis for experimental findings.
  • A signaling mechanism involving a transient GpA-like structure is suggested.
  • This model advances the understanding of integrin bidirectional signaling.

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