Article

Optical control of zebrafish behavior with halorhodopsin.

Department of Physiology, Program in Neuroscience, University of California, San Francisco, 1550 4th Street, San Francisco, CA 94158-2324, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 10/2009; 106(42):17968-73. DOI: 10.1073/pnas.0906252106
Source: PubMed

ABSTRACT Expression of halorhodopsin (NpHR), a light-driven microbial chloride pump, enables optical control of membrane potential and reversible silencing of targeted neurons. We generated transgenic zebrafish expressing enhanced NpHR under control of the Gal4/UAS system. Electrophysiological recordings showed that eNpHR stimulation effectively suppressed spiking of single neurons in vivo. Applying light through thin optic fibers positioned above the head of a semi-restrained zebrafish larva enabled us to target groups of neurons and to simultaneously test the effect of their silencing on behavior. The photostimulated volume of the zebrafish brain could be marked by subsequent photoconversion of co-expressed Kaede or Dendra. These techniques were used to localize swim command circuitry to a small hindbrain region, just rostral to the commissura infima Halleri. The kinetics of the hindbrain-generated swim command was investigated by combined and separate photo-activation of NpHR and Channelrhodopsin-2 (ChR2), a light-gated cation channel, in the same neurons. Together this "optogenetic toolkit" allows loss-of-function and gain-of-function analyses of neural circuitry at high spatial and temporal resolution in a behaving vertebrate.

Download full-text

Full-text

Available from: Filippo Del bene, Jul 04, 2015
0 Followers
 · 
175 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This chapter highlights current research using the embryonic zebrafish as a model system to study the effects of environmental toxicants on behavior. Zebrafish are ideally suited for high-throughput analyses of behavior. Hundreds of fertilized eggs can be collected daily from a single tank and the synchronously developing embryos can be exposed to environmental toxicants in a culture dish or multiwell plate. The developing motor network of the zebrafish embryo has been impressively characterized at multiple levels, from behavior to circuitry to genes, thus establishing a solid foundation for investigating mechanisms of neurobehavioral toxicity. Three assays are reviewed and their usage to screen for toxicant-induced behavioral defects in embryonic zebrafish is critically evaluated. The mechanisms of neurodevelopment are well conserved in vertebrate species in that similar genes, neurotransmitters, and hormones control early brain development and behavior in fish, mice, and humans. Consequently, behavioral assays in embryonic zebrafish may be used to screen for environmental toxicants that influence human brain development and behavior. Several recommendations are made to strengthen current approaches to accomplishing this important goal.
    Zebrafish, Edited by Charles Lessman, Ethan Carver, 04/2014: chapter 12: pages 245-264; Nova., ISBN: 978-1-63117-558-9
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Understanding how the brain implements social behavior on one hand, and how social processes feedback on the brain to promote fine-tuning of behavioral output according to changes in the social environment is a major challenge in contemporary neuroscience. A critical step to take this challenge successfully is finding the appropriate level of analysis when relating social to biological phenomena. Given the enormous complexity of both the neural networks of the brain and social systems, the use of a cognitive level of analysis (in an information processing perspective) is proposed here as an explanatory interface between brain and behavior. A conceptual framework for a cognitive approach to comparative social neuroscience is proposed, consisting of the following steps to be taken across different species with varying social systems: (1) identification of the functional building blocks of social skills; (2) identification of the cognitive mechanisms underlying the previously identified social skills; and (3) mapping these information processing mechanisms onto the brain. Teleost fish are presented here as a group of choice to develop this approach, given the diversity of social systems present in closely related species that allows for planned phylogenetic comparisons, and the availability of neurogenetic tools that allows the visualization and manipulation of selected neural circuits in model species such as the zebrafish. Finally, the state-of-the art of zebrafish social cognition and of the tools available to map social cognitive abilities to neural circuits in zebrafish are reviewed.
    Frontiers in Neural Circuits 08/2013; 7:131. DOI:10.3389/fncir.2013.00131 · 2.95 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Prey capture in zebrafish larvae is an innate behavior which can be observed as early as 4~days postfertilization, the day when they start to swim. This simple behavior apparently involves several neural processes including visual perception, recognition, decision-making, and motor control, and, therefore, serves as a good model system to study cognitive functions underlying natural behaviors in vertebrates. Recent progresses in imaging techniques provided us with a unique opportunity to image neuronal activity in the brain of an intact fish in real-time while the fish perceives a natural prey, paramecium. By expanding this approach, it would be possible to image entire brain areas at a single-cell resolution in real-time during prey capture, and identify neuronal circuits important for cognitive functions. Further, activation or inhibition of those neuronal circuits with recently developed optogenetic tools or neurotoxins should shed light on their roles. Thus, we will be able to explore the prey capture in zebrafish larvae more thoroughly at cellular levels, which should establish a basis of understanding of the cognitive function in vertebrates.
    Frontiers in Neural Circuits 06/2013; 7:110. DOI:10.3389/fncir.2013.00110 · 2.95 Impact Factor