Visual properties of transgenic rats harboring the channelrhodopsin-2 gene regulated by the thy-1.2 promoter.
Channelrhodopsin-2 (ChR2), one of the archea-type rhodopsins from green algae, is a potentially useful optogenetic tool for restoring vision in patients with photoreceptor degeneration, such as retinitis pigmentosa. If the ChR2 gene is transferred to retinal ganglion cells (RGCs), which send visual information to the brain, the RGCs may be repurposed to act as photoreceptors. In this study, by using a transgenic rat expressing ChR2 specifically in the RGCs under the regulation of a Thy-1.2 promoter, we tested the possibility that direct photoactivation of RGCs could restore effective vision. Although the contrast sensitivities of the optomotor responses of transgenic rats were similar to those observed in the wild-type rats, they were enhanced for visual stimuli of low-spatial frequency after the degeneration of native photoreceptors. This result suggests that the visual signals derived from the ChR2-expressing RGCs were reinterpreted by the brain to form behavior-related vision.
Tomita
Hiroshi
H
International Advanced Interdisciplinary Research, Tohoku University, Sendai, Japan. hiroshi-tomita@iiare.tohoku.ac.jp
Sugano
Eriko
E
Fukazawa
Yugo
Y
Isago
Hitomi
H
Sugiyama
Yuka
Y
Hiroi
Teru
T
Ishizuka
Toru
T
Mushiake
Hajime
H
Kato
Megumi
M
Hirabayashi
Masumi
M
Shigemoto
Ryuichi
R
Yawo
Hiromu
H
Tamai
Makoto
M
D000818:Animals; D030801:Animals, Genetically Modified; D001522:Behavior, Animal; D001921:Brain / Q000378:metabolism; D005786:Gene Expression Regulation; D051379:Mice; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism; D020419:Photoreceptor Cells, Vertebrate / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051381:Rats; D012165:Retinal Ganglion Cells / Q000378:metabolism; D012243:Rhodopsin / Q000096:biosynthesis* / Q000235:genetics*; D018800:Thy-1 Antigens / Q000235:genetics* / Q000378:metabolism; D014785:Vision, Ocular
D018800:Thy-1 Antigens; D012243:Rhodopsin