Abstract
Light offers superior control in terms of high temporal precision, high spatial precision, and non-invasiveness for the regulation of cellular functions. In recent years, chemical biologists have adopted chemo-optogenetic dimerization approaches, such as photo-triggered chemical inducers of dimerization (pCIDs), as a general tool for spatiotemporal regulation of cellular functions. Traditional chemo-optogenetic dimerization triggers either a single ON or a single OFF of cellular activity. However, more sophisticated approaches have been introduced in recent years. These include the ability to turn ON and OFF using different wavelengths of light, tools enabling multi-layer control of cellular activities, and nanobody-tethered photodimerizers. These advancements not only shed light on the study of ubiquitously existing multi-functional proteins but also create new opportunities for investigating complex cellular activity networks.