PUBLICATION

Differential Localization and Functional Roles of mGluR6 Paralogs in Zebrafish Retina

Authors
Haug, M., Haddad-Velioglu, S.A., Berger, M., Enz, A., Zang, J., Neuhauss, S.C.F.
ID
ZDB-PUB-241031-5
Date
2024
Source
Investigative ophthalmology & visual science   65: 4444 (Journal)
Registered Authors
Haug, Marion, Neuhauss, Stephan, Zang, Jingjing
Keywords
none
MeSH Terms
  • Retinal Cone Photoreceptor Cells/metabolism
  • Retinal Cone Photoreceptor Cells/physiology
  • Receptors, Metabotropic Glutamate*/genetics
  • Receptors, Metabotropic Glutamate*/metabolism
  • Retina/metabolism
  • Zebrafish*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
  • Electroretinography*
  • In Situ Hybridization*
  • Animals
  • Retinal Bipolar Cells/metabolism
  • Retinal Bipolar Cells/physiology
PubMed
39475940 Full text @ Invest. Ophthalmol. Vis. Sci.
Abstract
To define the location of mglur6 paralogs in the outer zebrafish retina and delineate their contribution to retina light responses across the visual spectrum.
In situ hybridization and immunolocalization with custom-made antibodies were used to localize mglur6 transcripts, proteins, and additional components of the mGluR6 signaling complex. Gene editing was used to generate knockout mutants that were analyzed with white light and spectral electroretinography.
Both mglur6 paralogs colocalized with known downstream pathway genes, such as trpm1a, nyctalopin, and gnaoβ. All rod photoreceptors contacted mGluR6-positive cells, while cone connectivity presented a more complex situation with no red cones and only a few UV and blue-sensitive cones connecting to mGluR6a-positive bipolar cells. All cone subtypes contacted mGluR6b-positive cells with markedly fewer red-sensitive cones. Retinas of knockout animals displayed no morphologic alterations. While ERG responses were unaffected in mglur6a knockout animals, mglur6b mutants displayed decreased responses over all spectral wavelengths.
We demonstrated that mGlurR6 signalplex components are similar in the zebrafish and the mammalian retina. Despite mglur6b knockout animals having significantly impaired ERG b-wave responses, a residual b-wave persists, even in double knockouts, suggesting additional pathway components yet to be identified.
Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping