Predicted to enable several functions, including RNA polymerase II cis-regulatory region sequence-specific DNA binding activity; bHLH transcription factor binding activity; and protein heterodimerization activity. Predicted to be involved in several processes, including Notch signaling pathway; negative regulation of neuron differentiation; and regulation of transcription by RNA polymerase II. Predicted to act upstream of or within negative regulation of muscle organ development and negative regulation of transcription by RNA polymerase II. Predicted to be active in nucleus. Orthologous to human HES1 (hes family bHLH transcription factor 1).