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bioRxiv · 10.1101/2022.03.02.482623

LITOS - a versatile LED illumination tool for optogenetic stimulation

Hoehener, T. C.·Landolt, A.·Dessauges, C.·Gagliardi, P. A.·Pertz, O.
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Abstract

Optogenetics has become a key tool to manipulate biological processes with high spatio-temporal resolution. Recently, a number of commercial and open-source multi-well illumination devices have been developed to provide throughput in optogenetics experiments. However, available commercial devices remain expensive and lack flexibility, while open-source solutions require programming knowledge and/or include complex assembly processes. We present a LED Illumination Tool for Optogenetic Stimulation (LITOS) based on an assembled printed circuit board controlling a commercially available 32x64 LED matrix as illumination source. LITOS can be quickly assembled without any soldering, and includes an easy-to-use interface, accessible via a website hosted on the device itself. Complex light stimulation patterns can easily be programmed without coding expertise. LITOS can be used with different formats of multi-well plates, petri dishes, and flasks. We validated LITOS by measuring the activity of the MAPK/ERK signaling pathway in response to different dynamic light stimulation regimes using FGFR1 and Raf optogenetic actuators. LITOS can uniformly stimulate all the cells in a well and allows for flexible temporal stimulation schemes. LITOSs ease of use aims at democratizing optogenetics in any laboratory.

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Hoehener, T. C., Landolt, A., Dessauges, C., Gagliardi, P. A., Pertz, O.. 2022-03-02. LITOS - a versatile LED illumination tool for optogenetic stimulation. https://doi.org/10.1101/2022.03.02.482623

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