Oral Presentation 2014 International Biophysics Congress

Molecular insights into the regulation of T cell signalling with single molecule localisation microscopy (#27)

Katharina Gaus 1
  1. Centre for Vascular Research, University of New South Wales, Sydney, NSW, Australia

T cell activation begins with the formation of signalling complexes at the cell surface involving the T cell antigen receptor (TCR), the Src family kinase Lck and the adaptor protein, linker for activation of T cells (LAT). How early TCR signalling events are regulated to prevent inopportune signalling in resting T cells but efficient activation upon receptor ligation is poorly understood. We have established single molecule localization microscopy to determine how TCR engagement reorganizes signalling proteins on the molecular scale. Imaging single molecules in intact cells has provided new insights into the mechanisms of Lck clustering (Rossy et al. Nat Immunol 2013) and LAT recruitment (Williamson et al. Nat Immunol 2011) upon TCR activation. We are now extending this work to elucidate how the membrane environment (Owen et al. Nat Commun 2012) and topography (Owen et al. Biophys J 2013) affects protein interactions to better understand the molecular principles of TCR signalling regulation.

Rossy J. Owen DM, Williamson D, Yang Z, Gaus K. (2013) Conformational states of Lck regulate clustering in early T cell signalling. Nature Immunol, 14, 82-9.

Owen DM, Williamson DJ, Boelen L, Magenau A, Rossy J, Gaus K. (2013) Quantitative analysis of 3-dimensional fluorescence localization microscopy data. Biophys J. 105, L05-7.

Owen DM, Williamson D, Magenau A, Gaus K. (2012) Sub-resolution lipid domains exist in the plasma membrane and regulate protein diffusion and distribution. Nat Commun. 4;3:1256

Williamson D, Owen DM, Rossy J, Magenau A, Wehrmann M, Gooding JJ, Gaus K. (2011) Pre-existing clusters of the adaptor Lat do not participate in early T cell signaling events. Nature Immunol, 12, 655-662.