Use of Channelrhodopsin for Activation of CNS Neurons

Abstract

Optogenetics – the use of optically-activated proteins to control neuronal function – is a recent development in neuroscience methodology. Optogenetic techniques provide a means of activating or inhibiting distinct populations of neurons with an unprecedented degree of spatial, temporal, and neurochemical precision. Channelrhodopsin-2 (ChR2), an algal protein from Chlamydomonas reinhardtii, is a light-activated cation channel capable of inducing depolarization and action potentials in neurons. Three protocols are presented in this unit for the use of ChR2, with emphasis on technical aspects of fiber optics. The first describes the use of ChR2 in electrophysiological recordings from brain slices. The second and third involve the use of ChR2 in vivo, with light delivered through chronic fiber implants or guide cannula.

Serotonergic versus Nonserotonergic Dorsal Raphe Projection Neurons: Differential Participation in Reward Circuitry

“…All lines were backcrossed onto a C57Bl6/J background. Mice were surgically injected with viral vectors (Table S1) and implanted with fiber optic cables (Britt et al, 2012b), the details of which are described in Supplemental Experimental Procedures. All animal procedures were approved by the National Institute on Drug Abuse’s animal care and use committee and carried out in accordance with National Institutes of Health Guide for the Care and Use of Laboratory Animals.…”

Optogenetic interrogations of the neural circuits underlying addiction

“…A wide variety of these proteins have now been optimized for use in neurons, including ion channels and pumps as well as G protein coupled receptors [20,21 • ,22]. To get selective expression of these proteins, DNA encoding the opsin is introduced into neurons in an anatomically restricted manner, commonly by viral delivery or in vivo electroporation [23,24]. Expression of the protein within neurons can be further restricted with the use of selective promoters or DNA recombination systems [25,26].…”

Genotype-dependent responsivity to inflammatory pain: A role for TRPV1 in the periaqueductal grey

“…Based on these findings, it is proposed that the LPAG/VLPAG -NA monosynaptic pathway transmits fear-driven central signals, which elicit bradycardia through parasympathetic outflow (Koba et al, 2016). Recently, optogenetic approaches have been used to study the role of basic synaptic properties of specific neural circuits in physiology and behaviour (Britt et al, 2012;Han, 2012).…”

“…Channelrhodopsin-2 (ChR2), an algal protein from Chlamydomonas reinhardtii, is the most common light-sensitive protein used (Britt et al, 2012;Han, 2012). Assareh et al…”