OLFM3 (olfactomedin 3), also known as NOE3, is a 478 amino acid protein that interacts with myocilin. Myocilin is an extracellular protein that plays a key role in the actomyosin system and is responsible for controlling intraocular pressure. OLFM3 is a secreted protein that contains an olfactomedin-like (OLF) domain, an approximately 260 amino acid motif commonly found in secreted glycoproteins. OLFM3 localizes to the Golgi apparatus of the cell and is highly expressed in both eye and brain tissue. Mutations in the gene that encodes OLFM3 may cause severe glaucoma, a condition in which increased intraocular pressure within the eyeball causes loss of eye sight.