December 2002
Volume 43, Issue 13
ARVO Annual Meeting Abstract  |   December 2002
Is ath5 Expression Regulated by Hedgehog (Hh) Signaling During Zebrafish Retinal Development
Author Affiliations & Notes
  • DL Stenkamp
    Biological Sciences University of Idaho Moscow ID
  • RA Frey
    Biological Sciences University of Idaho Moscow ID
  • Footnotes
    Commercial Relationships   D.L. Stenkamp, None; R.A. Frey, None. Grant Identification: Support: NIH Grant EY12146
Investigative Ophthalmology & Visual Science December 2002, Vol.43, 826. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      DL Stenkamp, RA Frey; Is ath5 Expression Regulated by Hedgehog (Hh) Signaling During Zebrafish Retinal Development . Invest. Ophthalmol. Vis. Sci. 2002;43(13):826.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Abstract: : Purpose: We wished to determine whether Hh signals from the midline, and/or from retinal structures, are important for the expression of ath5 during retinal neurogenesis. In embryonic zebrafish, Hh signaling arises from several sources (CNS midline, ganglion cells, and RPE) as the retina develops. Hh proteins can be considered candidates for a midline signal of unknown identity that is indirectly involved in regulating expression of retinal ath5, the vertebrate ortholog of the Drosophila gene, atonal. The ath5 gene product, a basic helix-loop-helix transcription factor, is in turn necessary for ganglion cell neurogenesis. Since Hh signaling from newly-specified ganglion cells is required to propagate retinal neurogenesis, and since hh regulates atonal in the developing Drosophila eye, a similar regulatory relationship has been speculated for the differentiating vertebrate retina. Method: Hh signaling was reduced by the use of sonic-you (syu) mutant zebrafish, which have a deletion in the sonic hedgehog (shh) gene, or by injecting antisense morpholino-conjugated oligonucleotides to knock down expression of both shh and tiggy-winkle hedgehog (twhh) at different developmental times. Expression of ath5 was examined by whole mount in situ hybridization. Results: In the syu mutants, the spatiotemporal pattern of ath5 expression appeared similar to that of wildtype siblings. Following injection of antisense morpholinos at 27 hpf (to disrupt Hh signaling in ganglion cells), some wildtype embryos showed reduced ath5 expression as compared to nonsense morpholino-injected controls. In embryos injected with antisense morpholinos at 10 hpf (to interfere with midline expression of Hh), ath5 expression was more severely affected. Conclusion: Hh signaling may be important for ath5 expression, but both Shh and Twhh must be knocked down. Hh signaling from ganglion cells during retinal neurogenesis, as well as from midline structures earlier in development, may both be important for regulating ath5 expression.

Keywords: 564 retinal development • 605 transcription factors • 415 ganglion cells 

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.