title: Channelrhodopsin-2 gene transduced into retinal ganglion cells restores functional vision in genetically blind rats.
abstract: To test the hypothesis that transduction of the channelrhodopsin-2 (ChR2) gene, a microbial-type rhodopsin gene, into retinal ganglion cells of genetically blind rats will restore functional vision, we recorded visually evoked potentials and tested the experimental rats for the presence of optomotor responses. The N-terminal fragment of the ChR2 gene was fused to the fluorescent protein Venus and inserted into an adeno-associated virus to make AAV2-ChR2V. AAV2-ChR2V was injected intravitreally into the eyes of 6-month-old dystrophic RCS (rdy/rdy) rats. Visual function was evaluated six weeks after the injection by recording visually evoked potentials (VEPs) and testing optomotor responses. The expression of ChR2V in the retina was investigated histologically. We found that VEPs could not be recorded from 6-month-old dystrophic RCS rats that had not been injected with AAV2-ChR2V. In contrast, VEPs were elicited from RCS rats six weeks after injection with AAV2-ChR2V. The VEPs were recorded at stimulation rates <20Hz, which was the same as that of normal rats. Optomotor responses were also significantly better after the AAV2-ChR2V injection. Expression of ChR2V was observed mainly in the retinal ganglion cells. These findings demonstrate that visual function can be restored in blind rats by transducing the ChR2V gene into retinal ganglion cells.
authors.affiliation: Tohoku University, Institute for International Advanced Interdisciplinary Research, 4-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575 Japan. hiroshi-tomita@iiare.tohoku.ac.jp <hiroshi-tomita@iiare.tohoku.ac.jp>
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tomita
authors.forename: Eriko
authors.initials: E
authors.lastname: Sugano
authors.forename: Hitomi
authors.initials: H
authors.lastname: Isago
authors.forename: Teru
authors.initials: T
authors.lastname: Hiroi
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Emi
authors.initials: E
authors.lastname: Ohta
authors.forename: Makoto
authors.initials: M
authors.lastname: Tamai
mesh_terms: D000818:Animals; D001766:Blindness / Q000235:genetics / Q000503:physiopathology / Q000628:therapy*; D002352:Carrier Proteins / Q000235:genetics*; D000229:Dependovirus / Q000235:genetics*; D005074:Evoked Potentials, Visual / Q000502:physiology; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D008297:Male; D017120:Nystagmus, Optokinetic / Q000502:physiology; D010775:Photic Stimulation; D051381:Rats; D011922:Rats, Mutant Strains; D012162:Retinal Degeneration / Q000235:genetics / Q000503:physiopathology / Q000628:therapy*; D012165:Retinal Ganglion Cells / Q000378:metabolism*; D013266:Stilbamidines / Q000378:metabolism; D014161:Transduction, Genetic
chemical_list: C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D002352:Carrier Proteins; D013266:Stilbamidines; C523009:channelopsin-2, Chlamydomonas reinhardtii