Enables DNA-binding transcription repressor activity, RNA polymerase II-specific and RNA polymerase II cis-regulatory region sequence-specific DNA binding activity. Involved in negative regulation of transcription, DNA-templated and regulation of myelination. Acts upstream of or within several processes, including negative regulation of transcription by RNA polymerase II; neurogenesis; and neuromuscular process controlling balance. Located in nucleus. Is expressed in several structures, including 4-cell stage embryo; central nervous system; gut; neural ectoderm; and thymus. Human ortholog(s) of this gene implicated in spastic ataxia 8. Orthologous to human NKX6-2 (NK6 homeobox 2). [provided by Alliance of Genome Resources, Apr 2022]