Title
Protein Gq modulates termination of phototransduction and prevents retinal degeneration
UMMS Affiliation
Department of Neurobiology; Hong-Sheng Li Lab; Graduate School of Biomedical Sciences, Neuroscience Program
Publication Date
2012-04-20
Document Type
Article
Subjects
Alleles; Animals; Animals, Genetically Modified; Arrestins; Drosophila Proteins; Drosophila melanogaster; Electrophysiology; GTP-Binding Protein alpha Subunits, Gq-G11; Light; Light Signal Transduction; Models, Genetic; Mutation; Photoreceptor Cells, Invertebrate; Receptors, G-Protein-Coupled; Retinal Degeneration; Rhodopsin
Disciplines
Biochemistry, Biophysics, and Structural Biology | Neuroscience and Neurobiology
Abstract
Appropriate termination of the phototransduction cascade is critical for photoreceptors to achieve high temporal resolution and to prevent excessive Ca(2+)-induced cell toxicity. Using a genetic screen to identify defective photoresponse mutants in Drosophila, we isolated and identified a novel Galpha(q) mutant allele, which has defects in both activation and deactivation. We revealed that G(q) modulates the termination of the light response and that metarhodopsin/G(q) interaction affects subsequent arrestin-rhodopsin (Arr2-Rh1) binding, which mediates the deactivation of metarhodopsin. We further showed that the Galpha(q) mutant undergoes light-dependent retinal degeneration, which is due to the slow accumulation of stable Arr2-Rh1 complexes. Our study revealed the roles of G(q) in mediating photoresponse termination and in preventing retinal degeneration. This pathway may represent a general rapid feedback regulation of G protein-coupled receptor signaling.
DOI of Published Version
10.1074/jbc.M112.339895
Source
J Biol Chem. 2012 Apr 20;287(17):13911-8. doi: 10.1074/jbc.M112.339895. Link to article on publisher's site
Journal/Book/Conference Title
The Journal of biological chemistry
Related Resources
PubMed ID
22389492
Repository Citation
Hu W, Wan D, Yu X, Cao J, Guo P, Li H, Han J. (2012). Protein Gq modulates termination of phototransduction and prevents retinal degeneration. Neurobiology Publications and Presentations. https://doi.org/10.1074/jbc.M112.339895. Retrieved from https://escholarship.umassmed.edu/neurobiology_pp/142
Comments
Co-author Peiyi Guo is a doctoral student in the Neuroscience Program in the Graduate School of Biomedical Sciences (GSBS) at UMass Medical School.