Resum
Manipulation of neuronal activity using two-photon excitation of azobenzene photoswitches with near-infrared light has been recently demonstrated, but their practical use in neuronal tissue to photostimulate individual neurons with three-dimensional precision has been hampered by firstly, the low efficacy and reliability of NIR-induced azobenzene photoisomerization compared to one-photon excitation, and secondly, the short cis state lifetime of the two-photon responsive azo switches. Here we report the rational design based on theoretical calculations and the synthesis of azobenzene photoswitches endowed with both high two-photon absorption cross section and slow thermal back-isomerization. These compounds provide optimized and sustained two-photon neuronal stimulation both in light-scattering brain tissue and in Caenorhabditis elegans nematodes, displaying photoresponse intensities that are comparable to those achieved under one-photon excitation. This finding opens the way to use both genetically targeted and pharmacologically selective azobenzene photoswitches to dissect intact neuronal circuits in three dimensions.
Citació
Cabré, Gisela; Garrido-Charles, Aida; Moreno, Miquel [et al]. Rationally designed azobenzene photoswitches for efficient two-photon neuronal excitation. Nature Communications, 2019, 10, 907. Disponible en: <https://www.nature.com/articles/s41467-019-08796-9>. Fecha de acceso: 2 feb. 2023. DOI: 10.1038/s41467-019-08796-9
Nota
G.C. acknowledges the “Generalitat de Catalunya” for her pre-doctoral FI grant. A.G.-C. was supported by fellowship BES-2014–068169. M.B. was supported by a Marie Curie Reintegration Grant (H2020-MSCA-IF). We are grateful to Ehud Isacoff (UC Berkeley) for sharing the LiGluR clone, to Dirk Trauner (NYU) for providing MAG compound, and to Anna Lledó i Lidia Bardia (IRBB imaging facility) for support in imaging experiments. We would like to acknowlegde César Alonso, Angel Sandoval, and Merche Rivas from the Biolab at ICFO for technical support in C. elegans experiments. We also acknowledge financial support from AGAUR/Generalitat de Catalunya (CERCA Programme and projects 2017-SGR-00465, 2017-SGR-1442, and 2017-SGR-1012), Severo Ochoa (SEV-2015–0522), Fundacion Privada Cellex, FEDER funds, ERANET SynBio MODULIGHTOR and Human Brain Project WAVESCALES projects, MINECO/FEDER (projects CTQ2015–65439-R, CTQ2016-80066-R, CTQ2016- 75363-R, CTQ2017-83745- P, and RYC-2015-17935), and Fundaluce and Ramón Areces foundations. M.K. acknowledges support through HFSP CDA and ERC MechanoSystems (715243).
