Acts as a transcriptional activator. Acts by binding to sequences related to the consensus octamer motif 5'-ATGCAAAT-3' in the regulatory regions of its target genes. May play a role in specifying terminally differentiated neuronal phenotypes. Interaction with ISL1. Preferentially localized in the nucleus. Expressed in the nervous system. Expressed in the otic vesicle during embryogenesis. Expressed in the adult retina in a subset of retinal ganglion cells (RGCs), and at a lower level in the adult tectum. Not expressed in the adult olfactory bulb. Weakly expressed during embryogenesis, with stronger expression in the adult eye. Belongs to the POU transcription factor family. Class-4 subfamily.