Enghild Lab Enghild Lab Enghild Lab Enghild Lab

Transforming growth factor beta induced protein (TGFBIP) and cornea dystrophies

Ida B. Thøgersen, Charlotte Sørensen, Ebbe Toftgaard Poulsen, Carsten S. Sonne-Schmidt, Kristian Sanggaard

Granular Type I The transforming growth factor beta induced protein (TGFBIp or bigH3) is an extracellular matrix protein encoded by the TGFBI (BIGH3) gene. According to alignment analyses the protein contains four fasciclin domains (FAS) and an RGD motif. TGFBIp interacts with different ligands and plays a role in cell adhesion. However, its specific physiological role is not clear. The TGFBI gene is expressed in many tissues but TGFBIp is especially abundant in the cornea. We have recently purified and characterized this protein from human and porcine corneas.

Mutations in the TGFBI gene are associated with an accumulation of TGFBIp in the cornea that lead to impaired vision. Some mutations cause the formation of amyloid in the cornea (lattice corneal dystrophies), while others generate crystalloid deposits in the cornea (granular corneal dystrophies). The biochemical and biophysical reasons for the deposits are unknown.