Browsing by Subject "optogenetics"

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    A wirelessly controlled implantable LED system for deep brain optogenetic stimulation.
    (Front Integr Neurosci, 2015) Rossi, Mark A; Go, Vinson; Murphy, Tracy; Fu, Quanhai; Morizio, James; Yin, Henry H
    In recent years optogenetics has rapidly become an essential technique in neuroscience. Its temporal and spatial specificity, combined with efficacy in manipulating neuronal activity, are especially useful in studying the behavior of awake behaving animals. Conventional optogenetics, however, requires the use of lasers and optic fibers, which can place considerable restrictions on behavior. Here we combined a wirelessly controlled interface and small implantable light-emitting diode (LED) that allows flexible and precise placement of light source to illuminate any brain area. We tested this wireless LED system in vivo, in transgenic mice expressing channelrhodopsin-2 in striatonigral neurons expressing D1-like dopamine receptors. In all mice tested, we were able to elicit movements reliably. The frequency of twitches induced by high power stimulation is proportional to the frequency of stimulation. At lower power, contraversive turning was observed. Moreover, the implanted LED remains effective over 50 days after surgery, demonstrating the long-term stability of the light source. Our results show that the wireless LED system can be used to manipulate neural activity chronically in behaving mice without impeding natural movements.
  • Thumbnail Image
    ItemOpen Access
    Genetically Encoded Photoactuators and Photosensors for Characterization and Manipulation of Pluripotent Stem Cells.
    (Theranostics, 2017) Pomeroy, Jordan E; Nguyen, Hung X; Hoffman, Brenton D; Bursac, Nenad
    Our knowledge of pluripotent stem cell biology has advanced considerably in the past four decades, but it has yet to deliver on the great promise of regenerative medicine. The slow progress can be mainly attributed to our incomplete understanding of the complex biologic processes regulating the dynamic developmental pathways from pluripotency to fully-differentiated states of functional somatic cells. Much of the difficulty arises from our lack of specific tools to query, or manipulate, the molecular scale circuitry on both single-cell and organismal levels. Fortunately, the last two decades of progress in the field of optogenetics have produced a variety of genetically encoded, light-mediated tools that enable visualization and control of the spatiotemporal regulation of cellular function. The merging of optogenetics and pluripotent stem cell biology could thus be an important step toward realization of the clinical potential of pluripotent stem cells. In this review, we have surveyed available genetically encoded photoactuators and photosensors, a rapidly expanding toolbox, with particular attention to those with utility for studying pluripotent stem cells.
  • Thumbnail Image
    ItemOpen Access
    Mechanisms Underlying Reshuffling of Visual Responses by Optogenetic Stimulation in Mice and Monkeys
    Sanzeni, Alessandro; Palmigiano, Agostina; Nguyen, Tuan H; Luo, Junxiang; Nassi, Jonathan J; Reynolds, John H; Histed, Mark H; Miller, Kenneth D; Brunel, Nicolas