Fig. 2.

Linker for activation of T cells (LAT)-mediated multiprotein signaling complexes. The phosphorylation of LAT on the distal four tyrosines results in the formation of several multiprotein signaling complexes with distinct composition and stoichiometry. These include complexes that contain either Grb2 or Grap and a reported interaction between PLC-γ1 and the Gads–SLP-76 complex. Vav and the p85 subunit of phosphatidylinositol (PI) 3-kinase may also interact with LAT, but whether these proteins directly or indirectly associate with LAT is still controversial. The result of the formation of LAT-mediated complexes is the activation of signaling pathways and the induction of effector functions.