TY - JOUR
T1 - Comparative Studies of the Fluorescence Properties of Microbial Rhodopsins
T2 - Spontaneous Emission Versus Photointermediate Fluorescence
AU - Kojima, Keiichi
AU - Kurihara, Rika
AU - Sakamoto, Masayuki
AU - Takanashi, Tsukasa
AU - Kuramochi, Hikaru
AU - Zhang, Xiao Min
AU - Bito, Haruhiko
AU - Tahara, Tahei
AU - Sudo, Yuki
N1 - Funding Information:
We thank Dr. Keisuke Ota for technical assistance to measure laser intensity in cultured neurons. This work was partially supported by JSPS-KAKENHI grant numbers JP19K16090 (to K.K.), JP17H05941, JP19H04898, JP20H04122 (to M.S.), JP18J00623 (to T.Tak), JP18H02411, JP19H04727, and JP19H05396 (to Y.S.), the Precise Measurement Technology Promotion Foundation (PMTP-F) (to M.S.), the Research Foundation for Opto-Science and Technology (to M.S.), the Konica Minolta Science and Technology Foundation (to M.S.), the Nakatani Foundation (to M.S.), and the Kowa Life Science Foundation (to M.S.). This work was also supported by a Grant-in-Aid for Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS) (20dm0207060h0004 to M.S. and Y.S.), Precursory Research for Embryonic Science and Technology (PRESTO) (to M.S. and H.K. [JPMJPR17P4]), and Brain Information Dynamics (BID) (to H.B.) grants from MEXT.
PY - 2020/8/27
Y1 - 2020/8/27
N2 - Rhodopsins are seven-transmembrane photoreceptor proteins that bind to the retinal chromophore and have been utilized as a genetically encoded voltage indicator (GEVI). So far, archaerhodopsin-3 (AR3) has been successfully used as a GEVI, despite its low fluorescence intensity. We performed comparative and quantitative fluorescence analyses of 15 microbial rhodopsins to explore these highly fluorescent molecules and to clarify their fluorescence mechanism. These rhodopsins showed a wide range of fluorescence intensities in mouse hippocampal neurons. Some of them, GR, HwBR, IaNaR, MR, and NpHR, showed fluorescence intensities comparable with or higher than that of AR3, suggesting their potential for GEVIs. The fluorescence intensity in neurons correlated with that of the bright fluorescent photointermediate such as a Q-intermediate (R = 0.75), suggesting that the fluorescence in neurons originates from the fluorescence of the photointermediate. Our findings provide a crucial step for producing next-generation rhodopsin-based GEVIs.
AB - Rhodopsins are seven-transmembrane photoreceptor proteins that bind to the retinal chromophore and have been utilized as a genetically encoded voltage indicator (GEVI). So far, archaerhodopsin-3 (AR3) has been successfully used as a GEVI, despite its low fluorescence intensity. We performed comparative and quantitative fluorescence analyses of 15 microbial rhodopsins to explore these highly fluorescent molecules and to clarify their fluorescence mechanism. These rhodopsins showed a wide range of fluorescence intensities in mouse hippocampal neurons. Some of them, GR, HwBR, IaNaR, MR, and NpHR, showed fluorescence intensities comparable with or higher than that of AR3, suggesting their potential for GEVIs. The fluorescence intensity in neurons correlated with that of the bright fluorescent photointermediate such as a Q-intermediate (R = 0.75), suggesting that the fluorescence in neurons originates from the fluorescence of the photointermediate. Our findings provide a crucial step for producing next-generation rhodopsin-based GEVIs.
UR - http://www.scopus.com/inward/record.url?scp=85090078480&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85090078480&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcb.0c06560
DO - 10.1021/acs.jpcb.0c06560
M3 - Article
C2 - 32790405
AN - SCOPUS:85090078480
VL - 124
SP - 7361
EP - 7367
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
SN - 1520-6106
IS - 34
ER -