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FRET detection of lymphocyte function-associated antigen-1 conformational extension.

ABSTRACT: Lymphocyte function-associated antigen 1 (LFA-1, CD11a/CD18, ?L?2-integrin) and its ligands are essential for adhesion between T-cells and antigen-presenting cells, formation of the immunological synapse, and other immune cell interactions. LFA-1 function is regulated through conformational changes that include the modulation of ligand binding affinity and molecular extension. However, the relationship between molecular conformation and function is unclear. Here fluorescence resonance energy transfer (FRET) with new LFA-1-specific fluorescent probes showed that triggering of the pathway used for T-cell activation induced rapid unquenching of the FRET signal consistent with extension of the molecule. Analysis of the FRET quenching at rest revealed an unexpected result that can be interpreted as a previously unknown LFA-1 conformation.

SUBMITTER: Chigaev A

PROVIDER: S-EPMC4279228 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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FRET detection of lymphocyte function-associated antigen-1 conformational extension.

Chigaev Alexandre A Smagley Yelena Y Haynes Mark K MK Ursu Oleg O Bologa Cristian G CG Halip Liliana L Oprea Tudor T Waller Anna A Carter Mark B MB Zhang Yinan Y Wang Wei W Buranda Tione T Sklar Larry A LA

Molecular biology of the cell 20141105 1

Lymphocyte function-associated antigen 1 (LFA-1, CD11a/CD18, αLβ2-integrin) and its ligands are essential for adhesion between T-cells and antigen-presenting cells, formation of the immunological synapse, and other immune cell interactions. LFA-1 function is regulated through conformational changes that include the modulation of ligand binding affinity and molecular extension. However, the relationship between molecular conformation and function is unclear. Here fluorescence resonance energy tra ...[more]

PMID: 25378583

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