FRET detection of lymphocyte function-associated antigen-1 conformational extension.
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 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.
Department of Pathology and Cancer Center, achigaev@salud.unm.edu lsklar@salud.unm.edu.
Alexandre
A
Chigaev
Department of Pathology and Cancer Center.
Yelena
Y
Smagley
University of New Mexico Center for Molecular Discovery, and.
Mark K
MK
Haynes
University of New Mexico Center for Molecular Discovery, and Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131.
Oleg
O
Ursu
University of New Mexico Center for Molecular Discovery, and Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131.
Cristian G
CG
Bologa
Department of Computational Chemistry, Institute of Chemistry, Romanian Academy, Timisoara 300223, Romania.
Liliana
L
Halip
University of New Mexico Center for Molecular Discovery, and Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131.
Tudor
T
Oprea
University of New Mexico Center for Molecular Discovery, and.
Anna
A
Waller
University of New Mexico Center for Molecular Discovery, and.
Mark B
MB
Carter
Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, Lexington, KY 40506.
Yinan
Y
Zhang
Department of Chemistry, University of New Mexico, Albuquerque, NM 87131.
Wei
W
Wang
Department of Pathology and Cancer Center.
Tione
T
Buranda
Department of Pathology and Cancer Center, University of New Mexico Center for Molecular Discovery, and.
Larry A
LA
Sklar
D002448:Cell Adhesion; D045744:Cell Line, Tumor; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D008024:Ligands; D008213:Lymphocyte Activation; D016169:Lymphocyte Function-Associated Antigen-1 / Q000737:chemistry*; D015394:Molecular Structure; D011487:Protein Conformation; D013601:T-Lymphocytes / Q000166:cytology
D005456:Fluorescent Dyes; D008024:Ligands; D016169:Lymphocyte Function-Associated Antigen-1