Parallel activin and BMP signaling coordinates R7/R8 photoreceptor subtype pairing in the stochastic Drosophila retina

  1. Brent S Wells
  2. Daniela Pistillo
  3. Erin Barnhart
  4. Claude Desplan  Is a corresponding author
  1. New York University, United States

Abstract

Drosophila color vision is achieved by comparing outputs from two types of color-sensitive photoreceptors, R7 and R8Ommatidia (unit eyes) are classified into two subtypes, known as 'pale' or 'yellow', depending on Rhodopsin expression in R7 and R8. Subtype specification is controlled by a stochastic decision in R7 and instructed to the underlying R8. We find that the Activin receptor Baboon is required in R8 to receive non-redundant signaling from the three Activin ligands, activating the transcription factor dSmad2. Concomitantly, two BMP ligands activate their receptor, Thickveins, and the transcriptional effector, Mad. The Amon TGFβ processing factor appears to regulate components of the TGFβ pathway specifically in pale R7. Mad and dSmad2 cooperate to modulate the Hippo pathway kinase Warts and the growth regulator Melted; two opposing factors of a bi-stable loop regulating R8 Rhodopsin expression. Therefore, TGFβ and growth pathways interact in postmitotic cells to precisely coordinate cell-specific output.

Article and author information

Author details

  1. Brent S Wells

    Center for Developmental Genetics, Department of Biology, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Daniela Pistillo

    Center for Developmental Genetics, Department of Biology, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Erin Barnhart

    Center for Developmental Genetics, Department of Biology, New York University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Claude Desplan

    Center for Developmental Genetics, Department of Biology, New York University, New York, United States
    For correspondence
    cd38@nyu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6914-1413

Funding

National Eye Institute (EY022843-01)

  • Brent S Wells

National Eye Institute (EY13012)

  • Claude Desplan

European Molecular Biology Organization (ALTF 506-2002)

  • Daniela Pistillo

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Bruce Edgar, University of Utah, United States

Version history

  1. Received: January 21, 2017
  2. Accepted: August 25, 2017
  3. Accepted Manuscript published: August 30, 2017 (version 1)
  4. Version of Record published: September 14, 2017 (version 2)

Copyright

© 2017, Wells et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Brent S Wells
  2. Daniela Pistillo
  3. Erin Barnhart
  4. Claude Desplan
(2017)
Parallel activin and BMP signaling coordinates R7/R8 photoreceptor subtype pairing in the stochastic Drosophila retina
eLife 6:e25301.
https://doi.org/10.7554/eLife.25301

Share this article

https://doi.org/10.7554/eLife.25301

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