Optogenetic Approaches for Controlling Neuronal Activity and Plasticity

Abstract Optogenetics combines the use of light-sensitive proteins with genetic targeting strategies. In recent years, the expanded optogenetic toolbox has broadened the understanding of cell communication and signaling from single units to entire networks. This chapter provides an overview of the latest molecular and engineering approaches to create a variety of optogenetic tools, which render neurons responsive to light. It starts by introducing different types of microbial and vertebrate light-activated proteins, their general properties, and applications. It then describes new light-activated proteins for fast optogenetic excitation and silencing of neurons with the main focus on recent modifications, mutants, and targeting strategies into specific cellular compartments. In addition, the chapter will also discuss the advantages of light-activated G protein–coupled receptors (GPCRs) and enzymes for controlling well-defined neuronal/cellular signaling cascades and protein–protein interactions for a broad range of applications.