Enables enzyme binding activity. Involved in Notch signaling pathway and positive regulation of smooth muscle cell proliferation. Acts upstream of or within several processes, including blood vessel morphogenesis; nervous system development; and regulation of transcription by RNA polymerase II. Located in nucleus and plasma membrane. Is expressed in several structures, including alimentary system; cardiovascular system; central nervous system; genitourinary system; and sensory organ. Used to study CADASIL 1 and acute lymphoblastic leukemia. Human ortholog(s) of this gene implicated in CADASIL 1; infantile myofibromatosis; and lateral meningocele syndrome. Orthologous to human NOTCH3 (notch receptor 3). [provided by Alliance of Genome Resources, Apr 2022]