Retinoic Acid Receptor-Related Orphan Receptors (RORs) in Eye Development and Disease

The retinoic acid receptor-related orphan receptors (RORs) are ligand-mediated transcription factors with important biological roles in regulating circadian rhythms, metabolism, immunity, angiogenesis, inflammation, and development. They belong to the superfamily of nuclear receptors and include three family members: RORα, RORβ, and RORγ. Currently identified ROR ligands include cholesterol and cholesterol derivatives for RORα and RORγ, and stearic acid and all-trans retinoic acid for RORβ. Aberrant signaling of the RORs is involved in the pathogenesis of several human diseases including autoimmune diseases, metabolic disorders, and certain cancers. In the eye, RORs regulate normal development of the lens and the retina, and also contribute to potentially blinding eye diseases, especially retinal vascular diseases. Here, we review the role of RORs in eye development and disease to highlight their potential as druggable targets for therapeutic development in retinal vascular and degenerative diseases.