Peripherin 2

Peripherin-2 is a is_associated_with::protein, that in humans is encoded by the PRPH2 is_associated_with::gene. Peripherin-2 is found in the rod and cone cells of the is_associated_with::retina of the is_associated_with::eye. Defects in this protein result in one form of is_associated_with::retinitis pigmentosa, an incurable blindness.

Mutations in the PRPH2 gene are associated with is_associated_with::Vitelliform macular dystrophy.

Function
The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the is_associated_with::tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four transmembrane helices. Tetraspanins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility.

Peripherin 2 (sometimes referred to as peripherin/RDS or simply RDS) is a cell surface is_associated_with::glycoprotein found in the outer segment of both rod and cone photoreceptor cells. It is located in the rim regions of the flattened disks that contain is_associated_with::rhodopsin, which is the protein that is responsible for initiation of visual phototransduction upon reception of light. Peripherin 2 may function as an adhesion molecule involved in stabilization and compaction of outer segment disks or in the maintenance of the curvature of the rim. This protein is essential for disk is_associated_with::morphogenesis.

Clinical significance
Defects in this gene are associated with both central and peripheral retinal degenerations. Some of the various phenotypically different disorders are autosomal dominant is_associated_with::retinitis pigmentosa, progressive is_associated_with::macular degeneration, macular dystrophy and retinitis pigmentosa digenic.