interphotoreceptor matrix proteoglycan 2 (sialoprotein associated with cones & rods proteoglycan, Spacrcan, interphotoreceptor matrix proteoglycan of 200 kD, IPM 200) (IMPG2 IPM200)

Function

• chondroitin sulfate- & hyaluronan-binding proteoglycan involved in organization of interphotoreceptor matrix
• may participate in the maturation & maintenance of the light-sensitive photoreceptor outer segment
• binds heparin

Structure

• highly glycosylated (N- & O-linked carbohydrates)
• contains 2 EGF-like domains
• contains 2 SEA domains

Compartment

membrane

Expression

• expressed in the retina
• pressed by photoreceptors of the interphotoreceptor matrix surrounding both rods & cones
• detected in the pineal gland

Polymorphism

• variations in IMPG2 coding region are implicated in inherited retinopathies

More general terms

• receptor
• proteoglycan
• membrane protein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:5093
• OMIM: https://mirror.omim.org/entry/607056
• UniProt: http://www.uniprot.org/uniprot/Q9BZV3.html