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Photolipid excitation triggers depolarizing optocapacitive currents and action potentials.

ABSTRACT: Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpolarization. As planar bilayer experiments show, the respective currents emerge from millisecond-timescale changes in bilayer capacitance. UV light changes photolipid conformation, which awards embedding plasma membranes with increased capacitance and evokes depolarizing currents. They open voltage-gated sodium channels in cells, generating action potentials. Blue light reduces the area per photolipid, decreasing membrane capacitance and eliciting hyperpolarization. If present, mechanosensitive channels respond to the increased mechanical membrane tension, generating large depolarizing currents that elicit action potentials. Membrane self-insertion of administered photolipids and focused illumination allows cell excitation with high spatiotemporal control.

SUBMITTER: Bassetto CAZ

PROVIDER: S-EPMC10462005 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Photolipid excitation triggers depolarizing optocapacitive currents and action potentials.

Bassetto Carlos A Z CAZ Pfeffermann Juergen J Yadav Rohit R Strassgschwandtner Simon S Glasnov Toma T Bezanilla Francisco F Pohl Peter P

bioRxiv : the preprint server for biology 20230814

Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpo ...[more]

PMID: 37645959

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Photolipid excitation triggers depolarizing optocapacitive currents and action potentials.

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Photolipid excitation triggers depolarizing optocapacitive currents and action potentials.

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