Optogenetic Technology and Its In Vivo Applications

Optogenetics is a novel technology with the widely acknowledged potential to revolutionize cell biology and neuroscience. Essentially, optogenetic methods integrate optical and genetic tools to control the activity of whole cells or subcellular events. In recent years, optogenetics has been used to activate and to inhibit genetically defined neuronal populations within neural circuits. As such, it has been used to show the sufficiency or the necessity of specific neuronal cell types in generating behaviors across a number of animal species. When employed in rodent models of human neurological and psychiatric disorders, optogenetics has provided clinically relevant insights into the function of pathologic neural circuits. Recent progress in the in vivo applications of this methodology is reviewed in this article, with particular focus on behavioral applications in nematodes, fish, rodents, and nonhuman primates.