KODAMA Takashi    Department   School of Medicine, School of Medicine    Position   Assistant Professor
Article types	Original article
Language	English
Peer review	Peer reviewed
Title	Expression and localization of an exogenous G protein-coupled receptor fused with the rhodopsin C-terminal sequence in the retinal rod cells of knockin mice.
Journal	Formal name：Experimental eye research Abbreviation：Exp Eye Res ISSN code：00144835/00144835
Domestic / Foregin	Foregin
Volume, Issue, Page	80(6),pp.859-69
Author and coauthor	Kodama Takashi, Imai Hiroo, Doi Tomoko, Chisaka Osamu, Shichida Yoshinori, Fujiyoshi Yoshinori
Authorship	Lead author
Publication date	2005/06
Summary	Vertebrate rod cell outer segments are highly differentiated compartments consisting of closely packed disk membranes, in which the photoreceptor rhodopsin is embedded at high density. To explore the unusually efficient mechanism of rhodopsin biosynthesis, folding and transport, we challenged it with the ectopic expression in rod cells of human endothelin receptor subtype B (hET(B)R) fused with the C-terminal 10 residues of rhodopsin, under the control of the mouse opsin promoter/enhancer, by gene targeted replacement (knockin), because the C-terminal eight residues are essential to target rhodopsin to the outer segment. The hET(B)R, a type-I G protein-coupled receptor, was successfully expressed and folded in a functional structure in the rod cells of knockin mice. However, while the mRNA level of hET(B)R was one tenth of that of rhodopsin, the hET(B)R protein level was approximately one-thousandth of the rhodopsin level in heterozygous mice, suggesting an intrinsically distinct efficiency in the production of functional receptor protein. In addition, a substantial fraction of the hET(B)R was successfully transported to the outer segment, suggesting that the addition of the C-terminal sequence of rhodopsin enabled hET(B)R to be translocated to the outer segment.
DOI	10.1016/j.exer.2004.12.017
PMID	15939043