Neuroscience Blog

Brain - Neuroscience Research Team.

Friday, August 24, 2007

Channelrhodopsin-2 - new perspectives

Posted by brain - research neuroscience group

Channelrhodopsin-2 is a cation channel from algae that depolarizes neurons in the presence of blue light. ChR2 will allow the study of neuronal circuits function by switching from on to off (and reverse) neurons from a neuronal network. So, in a network, the firing responess will be..."this" ...with all the neurons working, and in the same network the response will be..."that".. with the selected neurons switched off by ChR2 in the presence of the blue light, and then the network will be reversed to the original state!!. Smells like clinical neuroscience here!? Also ChR2 could be used in electrophysiological experiments to evoke neurotransmitter release, and it could be used in combination with neuroimaging techniques. Although the technique is new and several factors (see the links below) will have to be well managed in the experiments, combined techniques, including the use of ChR2 will give us a more precise perspective on how neuronal networks work.
ChR2, alone or combined with the other photostimulation techniques will be a minimally invasive technique, genetically targeted, and it will have temporally precise control of electrical activity of neurons. In oocytes of Xenopus laevis and mammalian cells, ChR2 is a
directly light-switched cation-selective ion channel and Petreanu et al. mapped the projections of pyramidal neurons in the barrel cortex using this method. Also, Arenkiel et al used this on mitral cells with the Thy1 promoter.
It is possible that the "classic" experiments to be reevaluated (where is possible) with this new method? Is this a new road in mental disorders research or a new way for the study of degenerative diseases of the brain? It is possible to evaluate in the future witch neuronal population is relevant to a behavior, witch population has a modulatory role in a behavior and witch population of neurons is dispensable? Hmm....

articles on this subject here
another article here
more about the subject here
and here
and you can find more from here
and more links here
and here too.

neuroscience bucharest blog team