Restoring the ON Switch in Blind Retinas: Opto-mGluR6, a Next-Generation, Cell-Tailored Optogenetic Tool

• DOI: 10.1371/journal.pbio.1002143
• Publication Date: 2015-05-07T17:51:39Z
• Authors: Michiel van Wyk; Justyna Pielecka-...; Siegrid Löwel; Sonja Kleinlogel
• Keywords: 0301 basic medicine; Mice, Inbred C3H; Retinal Bipolar Cells; QH301-705.5; Rod Opsins; Mice, Transgenic; Genetic Therapy; Blindness; Receptors, Metabotropic Glutamate; Optogenetics; 03 medical and health sciences; HEK293 Cells; Visual Perception; Animals; Humans; Biology (General); Vision, Ocular; Research Article

Photoreceptor degeneration is one of the most prevalent causes of blindness. Despite photoreceptor loss, the inner retina and central visual pathways remain intact over an extended time period, which has led to creative optogenetic approaches to restore light sensitivity in the surviving inner retina. The major drawbacks of all optogenetic tools recently developed and tested in mouse models are their low light sensitivity and lack of physiological compatibility. Here we introduce a next-generation optogenetic tool, Opto-mGluR6, designed for retinal ON-bipolar cells, which overcomes these limitations. We show that Opto-mGluR6, a chimeric protein consisting of the intracellular domains of the ON-bipolar cell-specific metabotropic glutamate receptor mGluR6 and the light-sensing domains of melanopsin, reliably recovers vision at the retinal, cortical, and behavioral levels under moderate daylight illumination.