通过靶向破坏代谢型谷氨酸受体6（mGluR6）基因，视觉传导中ON反应的特异性缺陷。

Specific deficit of the ON response in visual transmission by targeted disruption of the mGluR6 gene.

作者信息

Masu M, Iwakabe H, Tagawa Y, Miyoshi T, Yamashita M, Fukuda Y, Sasaki H, Hiroi K, Nakamura Y, Shigemoto R

机构信息

Institute for Immunology, Kyoto University Faculty of Medicine, Japan.

出版信息

Cell. 1995 Mar 10;80(5):757-65. doi: 10.1016/0092-8674(95)90354-2.

DOI:10.1016/0092-8674(95)90354-2

PMID:7889569

Abstract

Taking advantage of the restricted expression of metabotropic glutamate receptor subtype 6 (mGluR6) in retinal ON bipolar cells, we generated knockout mice lacking mGluR6 expression. The homozygous mutant mice showed a loss of ON responses but unchanged OFF responses to light. The mutant mice displayed no obvious changes in retinal cell organization nor in the projection of optic fibers to the brain. Furthermore, the mGluR6-deficient mice showed visual behavioral responses to light stimulation as examined by shuttle box avoidance behavior experiments using light exposure as a conditioned stimulus. The results demonstrate that mGluR6 is essential in synaptic transmission to the ON bipolar cell and that the OFF response provides an important means for transmitting visual information.

摘要

利用代谢型谷氨酸受体亚型6（mGluR6）在视网膜ON双极细胞中的限制性表达，我们培育出了缺乏mGluR6表达的基因敲除小鼠。纯合突变小鼠对光的ON反应丧失，但OFF反应未改变。突变小鼠的视网膜细胞组织以及视神经纤维向大脑的投射均未显示出明显变化。此外，通过以光照作为条件刺激的穿梭箱回避行为实验检测发现，mGluR6缺陷小鼠对光刺激表现出视觉行为反应。结果表明，mGluR6在向ON双极细胞的突触传递中至关重要，并且OFF反应为传递视觉信息提供了重要途径。