OptoRiboGenetics: Light-dependent Control of RNA function through PAL-RNA platform
1LIMES Institute (University of Bonn), Gerhard-Domagk-Strasse 1, Bonn, Germany
Sensory photoreceptors nurture light-dependent adaptations in nature and enable the optogenetic control of organismal behaviour and physiology. One such photoreceptor is PAL. PAL was identified in the a gram-positive actinobacterium Nakamurella multipartite. The acronym PAL is derived from its unique architecture, comprising of Per-ARNT-Sim (PAS), AmiR and NasR transcription antitermination regulators (ANTAR) and light-oxygen-voltage (LOV) domains. A crystal structure reconciles the unusual receptor architecture of PAL with C-terminal LOV photosensor and N-terminal effector units. This protein sequence-specifically binds to artificial RNA hairpin structures when exposed to blue light. This light-activated PAL-RNA complex is exploited for the spatio-temporal regulation of cellular processes such as transcription, translation, and mRNA processing in bacteria and mammalian cells. Furthermore, the PAL:RNA system is being established in vivo to control the gene expression in Drosophila Melanogaster using CRISPR activation.