Contributes to DNA-binding transcription factor activity. Acts upstream of or within determination of left/right symmetry and positive regulation of DNA-binding transcription factor activity. Predicted to be part of transcription regulator complex. Predicted to be active in nucleus. Is expressed in several structures, including forebrain neural keel; lens placode; nervous system; neural plate; and solid lens vesicle. Orthologous to human SOX1 (SRY-box transcription factor 1).