How does the kinase Lck phosphorylate the T cell receptor? Spatial organization as a regulatory mechanism

Abstract

T cell signaling begins with the ligation of the T cell antigen receptor (TCR) by a cognate peptide and the phosphorylation of the receptor's immunoreceptor tyrosine-based activa- tion motif domains by the kinase Lck. However, the canonical receptor model is insufficient to explain how the constitutively active kinase Lck can discriminate between non-ligated and ligated TCRs. Here, we discuss the factors that are thought to regulate the spatial distribution of theTCR and Lck, and therefore critically influenceTCR signaling initiation. © 2012 Rossy, Williamson and Gaus.