dictyNews Electronic Edition Volume 42, number 1 January 8, 2016 Please submit abstracts of your papers as soon as they have been accepted for publication by sending them to dicty@northwestern.edu or by using the form at http://dictybase.org/db/cgi-bin/dictyBase/abstract_submit. Back issues of dictyNews, the Dicty Reference database and other useful information is available at dictyBase - http://dictybase.org. Follow dictyBase on twitter: http://twitter.com/dictybase ========= Abstracts ========= Bitter tastant responses in the amoeba Dictyostelium correlate with rat and human taste assays Marco Cocorocchio1, Robert Ives2, David Clapham3, Paul L.R. Andrews4, Robin S.B. Williams1 1 Centre of Biomedical Sciences, School of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK 2 RD Platform Technology & Science, GlaxoSmithKline, Hertfordshire, SG1 2NY, UK 3 RD Platform Technology & Science, GlaxoSmithKline, Hertfordshire, SG12 ODP, UK 4 Division of Biomedical Science, St George’s University of London, SW17 0RE, UK published in ALTEX Treatment compliance is reduced when pharmaceutical compounds have a bitter taste and this is particularly marked for paediatric medications. Identification of bitter taste liability during drug discovery utilises the rat in vivo brief access taste aversion (BATA) test which apart from animal use is time consuming with limited throughput. We investigated the suitability of using a simple, non- animal model, the amoeba Dictyostelium discoideum to investigate taste-related responses and particularly identification of compounds with a bitter taste liability. The effect of taste-related compounds on Dictyostelium behaviour following acute exposure (15 minutes) was monitored. Dictyostelium did not respond to salty, sour, umami or sweet tasting compounds, however, cells rapidly responded to bitter tastants. Using time-lapse photography and computer-generated quantification to monitor changes in cell membrane movement, we developed an assay to assess the response of Dictyostelium to a wide range of structurally diverse known bitter compounds and blinded compounds. Dictyostelium showed varying responses to the bitter tastants, with IC50 values providing a rank order of potency. Comparison of Dictyostelium IC50 values to those observed in response to a similar range of compounds in the rat in vivo brief access taste aversion test showed a significant (p = 0.0172) positive correlation between the two models, and additionally a similar response to that provided by a human sensory panel assessment test. These experiments demonstrate that Dictyostelium may provide a suitable model for early prediction of bitterness for novel tastants and drugs. Interestingly, a response to bitter tastants appears conserved from single-celled amoebae to humans. submitted by: Robin Williams [robin.williams@rhul.ac.uk] ============================================================== [End dictyNews, volume 42, number 1]