@article{4bd4da8d14a048459b6954618436d014,
title = "Origin of the low thermal isomerization rate of rhodopsin chromophore",
abstract = "Low dark noise is a prerequisite for rod cells, which mediate our dim-light vision. The low dark noise is achieved by the extremely stable character of the rod visual pigment, rhodopsin, which evolved from less stable cone visual pigments. We have developed a biochemical method to quickly evaluate the thermal activation rate of visual pigments. Using an isomerization locked chromophore, we confirmed that thermal isomerization of the chromophore is the sole cause of thermal activation. Interestingly, we revealed an unexpected correlation between the thermal stability of the dark state and that of the active intermediate MetaII. Furthermore, we assessed key residues in rhodopsin and cone visual pigments by mutation analysis and identified two critical residues (E122 and I189) in the retinal binding pocket which account for the extremely low thermal activation rate of rhodopsin.",
author = "Masataka Yanagawa and Keiichi Kojima and Takahiro Yamashita and Yasushi Imamoto and Take Matsuyama and Koji Nakanishi and Yumiko Yamano and Akimori Wada and Yasushi Sako and Yoshinori Shichida",
note = "Funding Information: We would like to thank Prof. J. Nathans for providing us with the HEK293S cell line, Prof. S. Koike for HEK293T cell lines, Prof. R. S. Molday for the Rho 1D4-producing hybridoma, and Prof. H. Niwa for the pCAGGS vector. We would also like to thank Prof. T. Lamb for a critical reading of the manuscript. This work was supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan [Grants-in-Aid for Scientific Research 26840055 to M.Y., 25251036 and 26650119 to Y.S., and the Global Center of Excellence Program “Formation of a Strategic Base for Biodiversity and Evolutionary Research: from Genome to Ecosystem” (Program A06)], and RIKEN special postdoctoral researcher (SPDR) fellowship to M.Y.",
year = "2015",
month = jun,
day = "10",
doi = "10.1038/srep11081",
language = "English",
volume = "5",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
}