| Type: | Family | Name: | Peripherin/rom-1 |
| Description: | The outer segments of vertebrate rod photoreceptor cells are specialised organelles that function in the transduction of light into electrical signals as part of the visual excitation process. These organelles contain thousands of closely-stacked disk membranes, which have distinctly different protein compositions in their lamellar and rim regions []. Peripherin (or RDS) and rom-1 are related retinal-specific memebers of the tetraspanin family which are located at the rims of the photoreceptor disks, where they may act jointly in disk morphogenesis []. Both peripherin and rom-1 formdisulphide-linked homodimers. Defects in the peripherin gene (RDS) cause various human diseases such as autosomal dominant retinitis pigmentosa, autosomal dominant punctata albescens and butterfly-shaped pigment dystrophy. In mice it causes retinopathy known as 'retinal degeneration slow' (rds). These proteins contain about 350 amino acid residues. Structurally they consist of a short cytoplasmic N-terminal domain, followed by four transmembrane segments that delimit two lumenal and one cytoplasmic loops; the C-terminal domain is cytoplasmic. The second lumenal loop is very large (about 140 amino acid residues) and contains seven conserved cysteines. | Short Name: | Peripherin/rom-1 |
