Enables ligase activity. Involved in several processes, including negative regulation of JNK cascade; negative regulation of NF-kappaB transcription factor activity; and protein K48-linked ubiquitination. Acts upstream of or within several processes, including cellular protein metabolic process; negative regulation of alpha-beta T cell proliferation; and positive regulation of T cell anergy. Located in several cellular components, including cell cortex; cytoplasmic vesicle; and nucleus. Is expressed in several structures, including cardiovascular system; central nervous system; genitourinary system; gut; and sensory organ. Orthologous to human ITCH (itchy E3 ubiquitin protein ligase). [provided by Alliance of Genome Resources, Apr 2022]