title: The color-vision circuit in the medulla of Drosophila.
abstract: BACKGROUND
  Color vision requires comparison between photoreceptors that are sensitive to different wavelengths of light. In Drosophila, this is achieved by the inner photoreceptors (R7 and R8) that contain different rhodopsins. Two types of comparisons can occur in fly color vision: between the R7 (UV sensitive) and R8 (blue- or green sensitive) photoreceptor cells within one ommatidium (unit eye) or between different ommatidia that contain spectrally distinct inner photoreceptors. Photoreceptors project to the optic lobes: R1-R6, which are involved in motion detection, project to the lamina, whereas R7 and R8 reach deeper in the medulla. This paper analyzes the neural network underlying color vision into the medulla.
  
  
  RESULTS
  We reconstruct the neural network in the medulla, focusing on neurons likely to be involved in processing color vision. We identify the full complement of neurons in the medulla, including second-order neurons that contact both R7 and R8 from a single ommatidium, or contact R7 and/or R8 from different ommatidia. We also examine third-order neurons and local neurons that likely modulate information from second-order neurons. Finally, we present highly specific tools that will allow us to functionally manipulate the network and test both activity and behavior.
  
  
  CONCLUSIONS
  This precise characterization of the medulla circuitry will allow us to understand how color vision is processed in the optic lobe of Drosophila, providing a paradigm for more complex systems in vertebrates.
authors.affiliation: Center for Developmental Genetics, Department of Biology, New York University, 100 Washington Square East, New York, New York 10003, USA.
authors.forename: Javier
authors.initials: J
authors.lastname: Morante
authors.forename: Claude
authors.initials: C
authors.lastname: Desplan
mesh_terms: D000818:Animals; D003118:Color Perception / Q000502:physiology*; D004330:Drosophila / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000378:metabolism; D009899:Optic Lobe, Nonmammalian / Q000166:cytology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D014157:Transcription Factors