Disease relevance of IMPG2

• Organization of the human IMPG2 gene and its evaluation as a candidate gene in age-related macular degeneration and other retinal degenerative disorders [1].

High impact information on IMPG2

• SPACRCAN, a novel human interphotoreceptor matrix hyaluronan-binding proteoglycan synthesized by photoreceptors and pinealocytes [2].
• SPACRCAN was cloned from a human retinal cDNA library and the gene localized to chromosome 3q11 [2].
• SPACRCAN synthesized by photoreceptors is localized to the interphotoreceptor matrix where it surrounds both rods and cones [2].
• CONCLUSIONS: Analysis of the overall relationship of human IMPG2 (located on chromosome 3q12.2-12.3) to human IMPG1 (located on chromosome 6q14) suggests that these genes have evolved from a common ancestral gene [1].
• We report herein the characterization of the cDNA for a novel human chondroitin sulfate proteoglycan, designated IPM 200, and the chromosomal location of its gene, designated IMPG2 [3].

Biological context of IMPG2

• RESULTS: The IMPG2 gene is organized into 19 exons, and the structure of the gene is highly similar to that of the IMPG1 gene, which encodes another retinal proteoglycan, IPM 150 [1].
• IMPG2 maps to human chromosome 3q12.2-12 [3].
• The deduced IPM 200 core protein contains a putative transmembrane domain, two EGF-like repeats, numerous N- and O-linked glycosylation consensus sequences and one consensus sequence for glycosaminoglycan attachment [3].
• 3. Based on homologies within their amino acid sequences we propose that IPM 200 and a previously described human proteoglycan, IPM 150, form a new family of extracellular matrix glycoconjugates [3].

Anatomical context of IMPG2

• This space contains two chondroitin sulfate proteoglycans, designated IPM 150 and IPM 200, which are likely to effect retinal adhesion and photoreceptor survival [4].
• IPM 200 was isolated from the retinal interphotoreceptor matrix, a unique extracellular matrix that occupies the subretinal space between the apices of the retinal pigment epithelium and the neural retina [3].

Analytical, diagnostic and therapeutic context of IMPG2

• METHODS: After isolation of human genomic clones, the structure of IMPG2 was determined by sequence analysis [1].
• Additional data derived from RT-PCR and Northern blot analysis show that IMPG2 is processed in the human retina into multiple alternatively sized transcripts that may represent splicing isoforms [1].

References