In vivo spatiotemporal control of voltage-gated ion channels by using photoactivatable peptidic toxins

Abstract

Photoactivatable drugs targeting ligand-gated ion channels open up new opportunities for light-guided therapeutic interventions. Photoactivable toxins targeting ion channels have the potential to control excitable cell activities with low invasiveness and high spatiotemporal precision. As proof-of-concept, we develop HwTxIV-Nvoc, a UV light-cleavable and photoactivatable peptide that targets voltage-gated sodium (NaV) channels and validate its activity in vitro in HEK293 cells, ex vivo in brain slices and in vivo on mice neuromuscular junctions. We find that HwTxIV-Nvoc enables precise spatiotemporal control of neuronal NaV channel function under all conditions tested. By creating multiple photoactivatable toxins, we demonstrate the broad applicability of this toxin-photoactivation technology.

Optopharmacological tools for precise spatiotemporal control of oxytocin signaling in the central nervous system and periphery

“…Additionally, this compound can be applied to slices for hours without apparent toxic effects on neurons. We suggest that this tool will enable spatiotemporal delivery of oxytocin directly to the site of action over a range of areas and photorelease oxytocin in an analog or gradient manner by varying the amount of photolysis light (power and time) as demonstrated in previous studies with caged compounds (Banghart et al 2012; Durand-de Cuttoli et al 2020; Montnach et al 2022).…”

“…Oxytocin is an ideal candidate for caging because of its small size (nine amino acids) and established role in various biological functions. Photosensitive caging has previously been successfully achieved for other peptides of similar size (Banghart et al 2012; Montnach et al 2022). To generate oxytocin that is functionally inert until light exposure, we produced analogs where individual amino acids were replaced with photo-caged unnatural amino acid versions of the corresponding residue using solid-phase peptide synthesis.…”

Chemical and Biological Tools for the Study of Voltage‐Gated Sodium Channels in Electrogenesis and Nociception

“…This class of tools has been recently expanded with the development of the photocaged spider toxin HwTxIV-Nvoc. [141 The caged peptide toxin has demonstrable in vivo efficacy in both mice and zebrafish after several minutes of ultraviolet light application.…”

Macroscopic control of cell electrophysiology through ion channel expression

“…The activity of potassium channels can be locally modulated by voltage-gating, mechanical or light stimulus, and external ligands. In the last decade, advances in optogenetics and chemical biology of ion channels have powered numerous medical applications through local regulation of electrical activity in living cells with the ultimate goal of treating major life-threatening diseases ( Gradinaru et al, 2010 ; Häfner and Sandoz, 2022 ; Snyder, 2017 ; Montnach et al, 2022 ). Interestingly, recent studies indicate the spatial–temporal regulation of ion channel expression and membrane potential status is critical for landmarking pathological conditions such as cardiac arrhythmia, epilepsy, or various types of cancer ( Rosati and McKinnon, 2004 ; Lastraioli et al, 2015 ; Zsiros et al, 2009 ; Niemeyer et al, 2001 ; Biasiotta et al, 2016 ).…”