DATE2022.02.28 #Press Releases

Clever Membrane Proteins Transport Ions with Light

Disclaimer: machine translated by DeepL which may contain errors.

-Structural changes in light-driven ion pump rhodopsin as captured by XFEL

RIKEN

Tohoku University

University of Hyogo

Kyoto University

Japan Synchrotron Radiation Research Institute

The University of Tokyo

Summary

Team Leader Mikako Shiromizu and Engineer Toshiaki Hosaka of the Protein Function and Structure Research Team, RIKEN Center for Bioscience and Biotechnology; Team Leader Eriko Nango of the Molecular Animation Research Team, RIKEN Center for Synchrotron Radiation Science (Professor, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University); Group Director So Iwata of the SACLA Application Technology Development Group, RIKEN Center for Synchrotron Radiation Science (Professor, Graduate School of Medicine, Kyoto University); and Professor Minoru Kubo of the University of Hyogo's Graduate School of Science. Professor Minoru Kubo, Graduate School of Science, University of Hyogo, Chief Researcher Kensuke Tono, Center for Earth Surface System Dynamics for XFEL Research, Japan Synchrotron Radiation Research Institute, Professor Osamu Nureki, Graduate School of Science, The University of Tokyo, Associate Professor Susumu Yoshizawa, Center for Earth Surface System Dynamics, Atmosphere and Ocean Research Institute, The University of Tokyo, and other collaborators. Associate Professor Susumu Yoshizawa and his research group have elucidated the structural changes of "light-driven ion pumprodopsin," which is derived from marine bacteria that transport chloride ions ( ^Cl-) into cells in response to sunlight and other light sources, by high-resolution structural analysis using the X-ray free electron laser (XFEL) facility "SACLA The research results were obtained by high-resolution structural analysis using the X-ray free electron laser (XFEL) facility SACLA.

The research results are important for understanding the mechanism of ion transport in light-driven ion pomp rhodopsin, and are expected to be applied to further improvements in optogenetics, which uses light to manipulate neuronal and other cellular functions.

The light-driven ion pumprodopsin NM-R3 of the marine bacterium Nonlabens marinus has the ability to transport chloride ions toward the interior of cells.

This time, the joint research group succeeded in capturing the detailed structural changes of NM-R3 upon light irradiation by "time-resolved crystal structure analysis" using "SACLA". The results revealed the transport mechanism and route of chloride ion transport by NM-R3, as well as the existence of a clever mechanism to prevent backflow and overflow of ions.

This research was published online in the scientific journal " Proceedings of the National Academy of Sciences of the United States of America " on February 23.

Figure: Three-dimensional structure of light-driven ion pumprodopsin NM-R3 (blue circles indicate chloride ions in transport)

Professor Osamu Nureki of the Department of Biological Sciences and Project Assistant Professor Takatomo Nakane (at the time of the research) participated in this research.

For more information, please visit the RIKEN website.