Ophthalmology Commons^™

A Naturally Occurring Mutation Of The Opsin Gene (T4r) In Dogs Affects Glycosylation And Stability Of The G Protein-Coupled Receptor, Li Zhu, Geeng-Fu Jang, Beata Jastrzebska, Slawomir Filipek, Susan E. Pearce-Kelling, Gustavo D. Aguirre, Ronald E. Stenkamp, Gregory M. Acland, Krzysztof Palczewski

Gustavo D. Aguirre, VMD, PhD

Rho (rhodopsin; opsin plus 11-cis-retinal) is a prototypical G protein-coupled receptor responsible for the capture of a photon in retinal photoreceptor cells. A large number of mutations in the opsin gene associated with autosomal dominant retinitis pigmentosa have been identified. The naturally occurring T4R opsin mutation in the English mastiff dog leads to a progressive retinal degeneration that closely resembles human retinitis pigmentosa caused by the T4K mutation in the opsin gene. Using genetic approaches and biochemical assays, we explored the properties of the T4R mutant protein. Employing immunoaffinity-purified Rho from affected RHO^T4R/T4R dog retina, we found …