IMPG1
Developmental stage
Expressed in the retina lens at 6 weeks post-conception (WPC) (at protein level) (PubMed:29777959). Expressed in the neural retinal between 6 and 19 WPC (at protein level) (PubMed:29777959). Expressed in developing photoreceptors and emerging interphotoreceptor matrix between 12 and 19 WPC (at protein level) (PubMed:29777959).
Function
Chondroitin sulfate-, heparin- and hyaluronan-binding protein (By similarity). May serve to form a basic macromolecular scaffold comprising the insoluble interphotoreceptor matrix (PubMed:9813076).
Involvement in disease
Macular dystrophy, vitelliform, 4
VMD4
A form of macular dystrophy, a retinal disease in which various forms of deposits, pigmentary changes, and atrophic lesions are observed in the macula lutea. Vitelliform macular dystrophies are characterized by yellow, lipofuscin-containing deposits, usually localized at the center of the macula. VMD4 features include late-onset moderate visual impairment, small satellite drusen-like lesions in the foveal area, and preservation of retinal pigment epithelium reflectivity.
None
The disease is caused by variants affecting the gene represented in this entry.
Retinitis pigmentosa 91
RP91
A form of retinitis pigmentosa, a retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. RP91 is an autosomal dominant form with bone-spicule pigmentation, attenuation of retinal vessels, and optic disk pallor on funduscopy. Patients may also experience early macular involvement, with photophobia and reduced visual acuity, and some show a bull's eye pattern of macular atrophy.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
The N-terminus is blocked.
Highly glycosylated (N- and O-linked carbohydrates and sialic acid).
Tissue Specificity
Expressed in the retina (at protein level) (PubMed:10601738, PubMed:29777959). In the retina, specifically expressed by cone and rod photoreceptor cells (PubMed:9813076). Localizes to cone and rod photoreceptor cells surrounding the interphotoreceptor matrix of the retina (PubMed:9719680).
Cellular localization
- Cell projection
- Cilium
- Photoreceptor outer segment
- Secreted
- Extracellular space
- Extracellular matrix
- Interphotoreceptor matrix
- Photoreceptor inner segment
Alternative names
IPM150, SPACR, IMPG1, Interphotoreceptor matrix proteoglycan 1, Interphotoreceptor matrix proteoglycan of 150 kDa, Sialoprotein associated with cones and rods, IPM-150