Transcription factor that is thought to be involved in regulation of organogenesis. May be involved in determination and maintenance of retina formation. Binds a 5'-GGTGTCAG-3' motif present in the ARE regulatory element of ATP1A1. Binds a 5'-TCA[AG][AG]TTNC-3' motif present in the MEF3 element in the myogenin promoter, and in the IGFBP5 promoter (By similarity). Thought to be regulated by association with Dach and Eya proteins, and seems to be coactivated by EYA1, EYA2 and EYA3 (By similarity). Probably binds DNA dimer. Interacts with EYA3, and probably EYA1 and EYA2 (By similarity). Expressed in adult but not in fetal eyes. Found in corneal epithelium and endothelium, lens epithelium, ciliary body epithelia, cellular layers of the retina and the sclera. At the begin of fourth week of development detected in cytoplasm of somite cells, and at the end of fourth week is accumulated in the nucleus. Between the sixth and eighth week of development detected in the nucleus of limb bud cells. The disease is caused by variants affecting the gene represented in this entry. Belongs to the SIX/Sine oculis homeobox family. Aberrant splicing. Truncated C-terminus.