The expanding role of split protein complementation in opsin-free optogenetics.
blue
green
near-infrared
red
violet
BLUF domains
Cobalamin-binding domains
Cryptochromes
Fluorescent proteins
LOV domains
Phytochromes
Review
Abstract:
A comprehensive understanding of signaling mechanisms helps interpret fundamental biological processes and restore cell behavior from pathological conditions. Signaling outcome depends not only on the activity of each signaling component but also on their dynamic interaction in time and space, which remains challenging to probe by biochemical and cell-based assays. Opsin-based optogenetics has transformed neural science research with its spatiotemporal modulation of the activity of excitable cells. Motivated by this advantage, opsin-free optogenetics extends the power of light to a larger spectrum of signaling molecules. This review summarizes commonly used opsin-free optogenetic strategies, presents a historical overview of split protein complementation, and highlights the adaptation of split protein recombination as optogenetic sensors and actuators.
