Enables DNA-binding transcription activator activity, RNA polymerase II-specific; RNA polymerase II cis-regulatory region sequence-specific DNA binding activity; and chromatin DNA binding activity. Involved in positive regulation of neuron differentiation and positive regulation of transcription by RNA polymerase II. Acts upstream of or within several processes, including generation of neurons; inner ear morphogenesis; and positive regulation of inner ear auditory receptor cell differentiation. Located in nucleus. Is expressed in several structures, including alimentary system; central nervous system; ear; genitourinary system; and skin. Orthologous to human ATOH1 (atonal bHLH transcription factor 1). [provided by Alliance of Genome Resources, Apr 2022]