Main Menu (Mobile)- Block

Main Menu - Block

custom | custom

Search Results

general_search_page-panel_pane_1 | views_panes

3 Janelia Publications

Showing 1-3 of 3 results
Your Criteria:
    12/28/16 | Visual projection neurons in the Drosophila lobula link feature detection to distinct behavioral programs.
    Wu M, Nern A, Williamson WR, Morimoto MM, Reiser MB, Card GM, Rubin GM
    eLife. 2016 Dec 28;5:. doi: 10.7554/eLife.21022

    Visual projection neurons (VPNs) provide an anatomical connection between early visual processing and higher brain regions. Here we characterize lobula columnar (LC) cells, a class of Drosophila VPNs that project to distinct central brain structures called optic glomeruli. We anatomically describe 22 different LC types and show that, for several types, optogenetic activation in freely moving flies evokes specific behaviors. The activation phenotypes of two LC types closely resemble natural avoidance behaviors triggered by a visual loom. In vivo two-photon calcium imaging reveals that these LC types respond to looming stimuli, while another type does not, but instead responds to the motion of a small object. Activation of LC neurons on only one side of the brain can result in attractive or aversive turning behaviors depending on the cell type. Our results indicate that LC neurons convey information on the presence and location of visual features relevant for specific behaviors.

    View Publication Page
    10/24/16 | Central brain circuitry for color-vision-modulated behaviors.
    Longden KD
    Current Biology : CB. 2016 Oct 24;26(20):R981-8. doi: 10.1016/j.cub.2016.07.071

    Color is famous for not existing in the external world: our brains create the perception of color from the spatial and temporal patterns of the wavelength and intensity of light. For an intangible quality, we have detailed knowledge of its origins and consequences. Much is known about the organization and evolution of the first phases of color processing, the filtering of light in the eye and processing in the retina, and about the final phases, the roles of color in behavior and natural selection. To understand how color processing in the central brain has evolved, we need well-defined pathways or circuitry where we can gauge how color contributes to the computations involved in specific behaviors. Examples of such pathways or circuitry that are dedicated to processing color cues are rare, despite the separation of color and luminance pathways early in the visual system of many species, and despite the traditional definition of color as being independent of luminance. This minireview presents examples in which color vision contributes to behaviors dominated by other visual modalities, examples that are not part of the canon of color vision circuitry. The pathways and circuitry process a range of chromatic properties of objects and their illumination, and are taken from a variety of species. By considering how color processing complements luminance processing, rather than being independent of it, we gain an additional way to account for the diversity of color coding in the central brain, its consequences for specific behaviors and ultimately the evolution of color vision.

    View Publication Page
    08/10/16 | Natural courtship song variation caused by an intronic retroelement in an ion channel gene.
    Ding Y, Berrocal A, Morita T, Longden KD, Stern DL
    Nature. 2016 Aug 10:. doi: 10.1038/nature19093

    Animal species display enormous variation for innate behaviours, but little is known about how this diversity arose. Here, using an unbiased genetic approach, we map a courtship song difference between wild isolates of Drosophila simulans and Drosophila mauritiana to a 966 base pair region within the slowpoke (slo) locus, which encodes a calcium-activated potassium channel. Using the reciprocal hemizygosity test, we confirm that slo is the causal locus and resolve the causal mutation to the evolutionarily recent insertion of a retroelement in a slo intron within D. simulans. Targeted deletion of this retroelement reverts the song phenotype and alters slo splicing. Like many ion channel genes, slo is expressed widely in the nervous system and influences a variety of behaviours; slo-null males sing little song with severely disrupted features. By contrast, the natural variant of slo alters a specific component of courtship song, illustrating that regulatory evolution of a highly pleiotropic ion channel gene can cause modular changes in behaviour.

    View Publication Page