Interphotoreceptor matrix proteoglycan 2 (IMPG2, also known as SPACRCAN) is a interphotoreceptor matrix proteoglycan that binds to chondroitin sulfate and hyaluronan. It may be involved in organisation of the insoluble interphotoreceptor matrix [, ]. Mutations in the IMPG2 gene cause retinitis pigmentosa 56 (RP56) []and vitelliform macular dystrophy 5 (VMD5) [].
This entry includes interphotoreceptor matrix proteoglycans 1 and 2.IMPG1, also known as SPACR, is a sialoprotein associated with photoreceptor cones and rods protein. It is a secreted glycoprotein containing a central mucin-like domain and an EGF-like domain in the C-terminal region. It also contains two SEA domains (after sea urchin sperm protein, enterokinase, and agrin), a highly conserved structure composed of four anti-parallel beta sheets surrounded by alpha helices in an O-linked glycosylation-rich environment. IMPG1 has been linked to vitelliform macular dystrophies [].Interphotoreceptor matrix proteoglycan 2 (IMPG2, also known as SPACRCAN) is a interphotoreceptor matrix proteoglycan that binds to chondroitin sulfate and hyaluronan. It may be involved in organisation of the insoluble interphotoreceptor matrix [, ]. Mutations in the IMPG2 gene cause retinitis pigmentosa 56 (RP56) []and vitelliform macular dystrophy 5 (VMD5) [].
