Predicted to enable CARD domain binding activity and protein self-association. Involved in positive regulation of I-kappaB kinase/NF-kappaB signaling; positive regulation of NF-kappaB transcription factor activity; and positive regulation of T cell receptor signaling pathway. Acts upstream of or within several processes, including lymphocyte differentiation; positive regulation of interleukin-2 production; and regulation of lymphocyte activation. Located in immunological synapse. Human ortholog(s) of this gene implicated in diffuse large B-cell lymphoma; immunodeficiency 11A; and immunodeficiency 11B. Orthologous to human CARD11 (caspase recruitment domain family member 11). [provided by Alliance of Genome Resources, Apr 2022]