Sensory Coding in Drosophila Larvae

The fruit fly larva is receive information of various sensory modalities. Our research is focussed on the identification of the cellular, molecular and genetic mechanisms underlying vision and gustation in this seemingly simple animal using behavioral studies and circuit analyses.

Larvae are typically photophobic: it does not like to be exposed to light and navigates to move away from the light source. For this behavior only one of the two photoreceptor types is required. The four blue-sensitive Rh5-photoreceptors are necessary for light avoidance, while the green-sensitive Rh6-photoreceptors are dispensable (Keene at al., 2011). A set of three neurons in the brain are further acting downstream or the larval eye to mediate light avoidance. While all three neurons belong to the clock circuit, only one neuron contacts the larval photoreceotor, the 5th-LN (Keene et al., 2011; Keene and Sprecher, 2012).

The taste system allows animals to distinguish the quality, nutritional content of food or if it contains toxic substances. We developed a microfulidics devise, which allows us to study the responses of all sensory neurons with unprecedented precision. Combining this information with single cell transcriptomics we are able to reconstitute a complete map of the taste organs and identify the fundamental principles of gustation.

 

Relevant publications:

Larderet I, Fritsch P, Gendre N, Neagu-Maier L, Fetter RD, Schneider-Micell CM, Truman JW, Zlatic M, Cardona A, Sprecher SG                                                                 Organization of the Drosophila larval visual circuit                          eLife 10.7554/eLife.28387

van Giesen L, Neagu-Maier GL, Kwon JY, Sprecher SG.                                                      A microfluidics-based method for measuring neuronal activity in Drosophila chemosensory neurons.                                                                                                       Nature Protocols 2016 Dec;11(12):2389-2400. doi: 10.1038/nprot.2016.144.

van Giesen L, Hernandez-Nunez L, Delasoie-Baranek S, Colombo M, Renaud P, Bruggmann R, Benton R, Samuel ADT, and  Sprecher SG                                    Multimodal stimulus coding by a gustatory sensory neuron in Drosophila larvae           Nature Communications, 2016 Feb 11;7:10687. doi: 10.1038/ncomms10687.

Humberg TH and Sprecher SG                                                                                          Age- and wavelength-dependency of Drosophila larval phototaxis and behavioral responses to natural lighting conditions                                                                           Front Behav Neurosci, 20 April 2017

Pauls D, von Essen A, Lyutova R, van Giesen L, Rosner R, Wegner C, Sprecher SG    Potency of transgenic effectors for neurogenetic manipulations in Drosophila larvae Genetics, 2015 Jan;199(1):25-37

Klein M, Afonso B, Vonner AJ, Hernandez-Nunez L, Berck M, Tabone CJ, Kane EA, Pieribone VA, Nitabach MN, Cardona A, Zlatic M, Sprecher SG, Gershow M, Garrity PA, Samuel AD                                                                                                                   Sensory determinants of behavioral dynamics in Drosophila thermotaxis.                      Proc Natl Acad Sci U S A. 2015 Jan 13;112(2):E220-9.

Kane EA, Gershow M, Afonso B, Larderet I, Klein M, Carter AR, de Bivort BL, Sprecher SG, Samuel AD.
Sensorimotor structure of Drosophila larva phototaxis.
Proc Natl Acad Sci U S A. 2013 Sep 16.

Keene AC, Mazzoni EO, Zhen J, Younger MA, Yamaguchi S, Blau J, Desplan C and Sprecher SG                                                                                                                     Distinct visual pathways mediate Drosophila larval light avoidance and circadian clock entrainment. J NEUROSCI. 2011 Apr 27;31(17):6527-34.

Diaz NN and Sprecher SG                                                                                     Photoreceptors: Unconventional ways of seeing. CURR BIOL. 2011 Jan 11;21 (1):R25-7

Keene AC and Sprecher SG.                                                                                                 Seeing the light: photobehavior in fruit fly larvae, Trends Neurosci. 2012 Feb;35(2):104-10