Introduction to Part II: Natural Photosensitive Proteins

Light sensing in nature has had the benefit of evolutionary time to optimize light-sensing and �photoresponsive molecular systems. Molecular biologists and neurobiologists have recently discovered that these optimized systems can be adapted for very specific purposes and to fill a need in the neuroscience community. Myriad research groups have now employed natural photosensitive proteins in experiments where precise control of neuronal firing is desired without the use of traditional electrodes or perfusion devices. More recently, complementary light-sensing systems have been introduced that also allow researchers to apply light from afar that silences neuronal activity.