NRSC 4132 Blog

Every now and again an idea or a thing comes along that strikes a nerve and resonates with everyone. In fashion in 2010 it was a pair of shoes by Alexander McQueen called Armadillos. Nobody didn?t have an opinion about these fantastical lobster claw monstrosities that were somehow beautiful despite their blatant disregard for the practical physics of human locomotion. Similarly in 2010 the field of optogenetics burst onto the scientific scene and absolutely enthralled the neuroscience community. While Lady Gaga popularized McQueen?s strange but fascinating shoes in her videos and the MET displayed a pair in a fashion exhibit, the equally intriguing discipline of optogenetics was named method of the year across all of science and engineering by the journal Nature Methods and laboratories across the globe scrambled to hop on the bandwagon. This month the journal Neuron published a primer titled Optogenetics in Neural Systems by researchers at Stanford University.
The primer gives a thorough context to this rapidly emerging field starting with none other than Francis Crick. In 1979 the famed scientist recognized that a major challenge facing neuroscience was the need for a cell specific stimulator that unlike the electrode would be able to control activity in one cell type while leaving the others unaltered. Later, he even went so far as to suggest light could be a useful tool, but did not make the connection between this thought and research done years earlier on the microbial single-component light-activated ion pump bacteriorhodopsin. It wasn?t until 2005 that introduction of an opsin gene into mammalian neurons resulted in the control of action potentials.
The discovery of the three classes of opsins (haloarchael bacteriorhodopsin ,halorhodopsin, and channelrhodopsin) is detailed along with their specific uses. These genes now allow neuroscientists to manipulate neurons and cause ?fast excitation, fast inhibition, bistable modulation, and intracellular biochemical signaling? on demand.
The paper further discusses targeting techniques such as viruses, projection targeting, transgenic animal targeting, and spaciotemporal targeting. Viral vectors such as lentivirus and adeno-associated virus have been successfully used to introduce opsins to mouse, rat, and primate brains, and projection targeting may prove even more exciting as it makes it possible to illuminate and excite cells based on their connectivity.
Not only does this primer provide a detailed background of optogenetics, but it touches on nearly every possible aspect involved in actually setting up a successful optogenetics rig in a laboratory setting including light requirements for activation, light delivery, and light sources (with sections on lasers, LEDs, and incandescent sources).
Unlike the Armadillo shoes, who despite the stir they caused in the fashion world last year have fallen off of the radar, optogenetics isn?t a passing fad. It is the beginning of a complete re-imagining of how we study the brain. It is by far one of the most creative and clever methods I have ever seen. It is ingenious in concept, but somehow simple and elegant when compared to complicated drug targets and indiscriminate electrodes. We are at a place in neuroscience where the advancements we are likely to see in even the next 10 years will be even more unbelievable than McQueen?s Armadillos becoming a staple in every woman?s wardrobe. I am excited to see the development in this field and I?m sure we will still be talking about optogenetics in 2012 even if next year?s foot fad has progressed to include ACTUAL armadillos. More here: http://www.cell.com/neuron/abstract/S0896-6273%2811%2900504-6