| First Author | Lu Q | Year | 2018 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 59 |
| Issue | 3 | Pages | 1288-1294 |
| PubMed ID | 29625451 | Mgi Jnum | J:261661 |
| Mgi Id | MGI:6151239 | Doi | 10.1167/iovs.17-23278 |
| Citation | Lu Q, et al. (2018) A Robust Optomotor Assay for Assessing the Efficacy of Optogenetic Tools for Vision Restoration. Invest Ophthalmol Vis Sci 59(3):1288-1294 |
| abstractText | Purpose: To develop an animal behavioral assay for the quantitative assessment of the functional efficacy of optogenetic therapies. Methods: A triple-knockout (TKO) mouse line, Gnat1-/-Cnga3-/-Opn4-/-, and a double-knockout mouse line, Gnat1-/-Cnga3-/-, were employed. The expression of channelrhodopsin-2 (ChR2) and its three more light-sensitive mutants, ChR2-L132C, ChR2-L132C/T159C, and ChR2-132C/T159S, in inner retinal neurons was achieved using rAAV2 vectors via intravitreal delivery. Pupillary constriction was assessed by measuring the pupil diameter. The optomotor response (OMR) was examined using a homemade optomotor system equipped with light-emitting diodes as light stimulation. Results: A robust OMR was restored in the ChR2-mutant-expressing TKO mice; however, significant pupillary constriction was observed only for the ChR2-L132C/T159S mutant. The ability to evoke an OMR was dependent on both the light intensity and grating frequency. The most light-sensitive frequency for the three ChR2 mutants was approximately 0.042 cycles per degree. Among the three ChR2 mutants, ChR2-L132C/T159S was the most light sensitive, followed by ChR2-L132C/T159C and ChR2-L132C. Melanopsin-mediated pupillary constriction resulted in a substantial reduction in the light sensitivity of the ChR2-mediated OMR. Conclusions: The OMR assay using TKO mice enabled the quantitative assessment of the efficacy of different optogenetic tools and the properties of optogenetically restored vision. Thus, the assay can serve as a valuable tool for developing effective optogenetic therapies. |
