TY - JOUR TI - Time-resolved serial femtosecond crystallography reveals early structural changes in channelrhodopsin AU - Oda, Kazumasa AU - Nomura, Takashi AU - Nakane, Takanori AU - Yamashita, Keitaro AU - Inoue, Keiichi AU - Ito, Shota AU - Vierock, Johannes AU - Hirata, Kunio AU - Maturana, Andrés D AU - Katayama, Kota AU - Ikuta, Tatsuya AU - Ishigami, Itsuki AU - Izume, Tamaki AU - Umeda, Rie AU - Eguma, Ryuun AU - Oishi, Satomi AU - Kasuya, Go AU - Kato, Takafumi AU - Kusakizako, Tsukasa AU - Shihoya, Wataru AU - Shimada, Hiroto AU - Takatsuji, Tomoyuki AU - Takemoto, Mizuki AU - Taniguchi, Reiya AU - Tomita, Atsuhiro AU - Nakamura, Ryoki AU - Fukuda, Masahiro AU - Miyauchi, Hirotake AU - Lee, Yongchan AU - Nango, Eriko AU - Tanaka, Rie AU - Tanaka, Tomoyuki AU - Sugahara, Michihiro AU - Kimura, Tetsunari AU - Shimamura, Tatsuro AU - Fujiwara, Takaaki AU - Yamanaka, Yasuaki AU - Owada, Shigeki AU - Joti, Yasumasa AU - Tono, Kensuke AU - Ishitani, Ryuichiro AU - Hayashi, Shigehiko AU - Kandori, Hideki AU - Hegemann, Peter AU - Iwata, So AU - Kubo, Minoru AU - Nishizawa, Tomohiro AU - Nureki, Osamu A2 - Kruse, Andrew C A2 - Swartz, Kenton J A2 - Hekstra, Doeke VL - 10 PY - 2021 DA - 2021/03/23 SP - e62389 C1 - eLife 2021;10:e62389 DO - 10.7554/eLife.62389 UR - https://doi.org/10.7554/eLife.62389 AB - Channelrhodopsins (ChRs) are microbial light-gated ion channels utilized in optogenetics to control neural activity with light . Light absorption causes retinal chromophore isomerization and subsequent protein conformational changes visualized as optically distinguished intermediates, coupled with channel opening and closing. However, the detailed molecular events underlying channel gating remain unknown. We performed time-resolved serial femtosecond crystallographic analyses of ChR by using an X-ray free electron laser, which revealed conformational changes following photoactivation. The isomerized retinal adopts a twisted conformation and shifts toward the putative internal proton donor residues, consequently inducing an outward shift of TM3, as well as a local deformation in TM7. These early conformational changes in the pore-forming helices should be the triggers that lead to opening of the ion conducting pore. KW - channelrhodopsin KW - Chlamydomonas reinhardtii KW - C1C2 JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -