May be important in developing and maintaining corneal transparency and for the structure of the stromal matrix.
Cornea. Increased expression in the stroma of keratoconus corneas. Also detected in trachea, and in low levels, in intestine, skeletal muscle, ovary, lung and putamen.
Defects in KERA are the cause of the autosomal recessive cornea plana 2 (CNA2) [MIM:217300]. In CNA2, the forward convex curvature is flattened, leading to a decrease in refraction, reduced visual activity, extreme hyperopia (usually plus 10 d or more), hazy corneal limbus, opacities in the corneal parenchyma, and marked arcus senilis (often detected at an early age). CNA2 is a rare disorder with a worldwide distribution, but a high prevalence in the Finnish population.
Belongs to the small leucine-rich proteoglycan (SLRP) family. SLRP class II subfamily. Contains 10 LRR (leucine-rich) repeats. Contains 1 LRRNT domain.
Binds keratan sulfate chains.
Secreted > extracellular space > extracellular matrix.