Predicted to enable protein kinase binding activity and signaling receptor complex adaptor activity. Acts upstream of or within gene expression; inflammatory response; and lymphocyte homeostasis. Located in cell-cell junction and immunological synapse. Part of COP9 signalosome. Is expressed in liver and thymus primordium. Used to study IgG4-related disease. Human ortholog(s) of this gene implicated in immunodeficiency 52. Orthologous to human LAT (linker for activation of T cells). [provided by Alliance of Genome Resources, Apr 2022]