Abstract | PURPOSE: Mutations in the photoreceptor-specific protein peripherin/rds are associated with multiple retinal diseases. To date, attempts to achieve complete structural and functional rescue in animal models of peripherin/rds-induced retinal degeneration have not been successful. Gene therapy-directed approaches have been hindered by the haploinsufficiency phenotype, which dictates well-regulated expression of peripherin/rds protein levels. METHODS: Using a transgenic mouse line expressing wild-type peripherin/rds (NMP), the authors evaluated the critical in vivo level of peripherin/rds needed to maintain photoreceptor structure and ERG function and assessed the consequences of peripherin/rds overexpression in both rods and cones by Western blot and immunoprecipitation analyses, immunohistochemistry, electron microscopy, and electroretinography. The NMP transgene included a C-terminal modification (P341Q) to facilitate detection of the transgenic protein in the presence of wild-type peripherin/rds, using the monoclonal antibody 3B6. RESULTS:
Peripherin/rds protein levels in NMP homozygotes were approximately 60% of wild-type levels. Western blot and immunoprecipitation analyses confirmed normal biochemical properties of the NMP protein when compared with wild-type peripherin/rds. Immunohistochemistry demonstrated appropriate localization of transgenic peripherin/rds protein to the disc rim region of photoreceptor outer segments. Total peripherin/rds levels in the retina were modulated by crossing NMP transgenic mice into different rds genetic backgrounds. A positive correlation was observed between peripherin/rds expression levels and the structural and functional integrity of photoreceptor outer segments. Overexpression of peripherin/rds caused no detectable adverse effects on rod or cone structure and function. CONCLUSIONS: These findings may have significant implications regarding therapeutic intervention in peripherin/rds-associated retinal diseases.
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Authors | May Nour, Xi-Qin Ding, Heidi Stricker, Steven J Fliesler, Muna I Naash |
Journal | Investigative ophthalmology & visual science
(Invest Ophthalmol Vis Sci)
Vol. 45
Issue 8
Pg. 2514-21
(Aug 2004)
ISSN: 0146-0404 [Print] United States |
PMID | 15277471
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Intermediate Filament Proteins
- Membrane Glycoproteins
- Nerve Tissue Proteins
- Peripherins
- Prph2 protein, mouse
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Topics |
- Animals
- Blotting, Western
- Electroretinography
- Female
- Fluorescent Antibody Technique, Indirect
- Gene Expression Regulation
(physiology)
- Immunoblotting
- Intermediate Filament Proteins
(genetics, metabolism)
- Male
- Membrane Glycoproteins
(genetics, metabolism)
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Nerve Tissue Proteins
(genetics, metabolism)
- Peripherins
- Photoreceptor Cells, Vertebrate
(metabolism, ultrastructure)
- Precipitin Tests
- Retinal Degeneration
(metabolism, pathology)
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