PUBLICATION

Defect patterns on the curved surface of fish retinae suggest a mechanism of cone mosaic formation

Authors
Nunley, H., Nagashima, M., Martin, K., Lorenzo Gonzalez, A., Suzuki, S.C., Norton, D.A., Wong, R.O.L., Raymond, P.A., Lubensky, D.K.
ID
ZDB-PUB-201216-13
Date
2020
Source
PLoS Computational Biology   16: e1008437 (Journal)
Registered Authors
Nagashima, Mikiko, Raymond, Pamela, Wong, Rachel
Keywords
none
MeSH Terms
  • Computer Simulation
  • Animals
  • Zebrafish/anatomy & histology*
  • Zebrafish/growth & development
  • Cell Communication
  • Cell Differentiation
  • Retinal Cone Photoreceptor Cells/metabolism*
(all 7)
PubMed
33320887 Full text @ PLoS Comput. Biol.
Abstract
The outer epithelial layer of zebrafish retinae contains a crystalline array of cone photoreceptors, called the cone mosaic. As this mosaic grows by mitotic addition of new photoreceptors at the rim of the hemispheric retina, topological defects, called "Y-Junctions", form to maintain approximately constant cell spacing. The generation of topological defects due to growth on a curved surface is a distinct feature of the cone mosaic not seen in other well-studied biological patterns like the R8 photoreceptor array in the Drosophila compound eye. Since defects can provide insight into cell-cell interactions responsible for pattern formation, here we characterize the arrangement of cones in individual Y-Junction cores as well as the spatial distribution of Y-junctions across entire retinae. We find that for individual Y-junctions, the distribution of cones near the core corresponds closely to structures observed in physical crystals. In addition, Y-Junctions are organized into lines, called grain boundaries, from the retinal center to the periphery. In physical crystals, regardless of the initial distribution of defects, defects can coalesce into grain boundaries via the mobility of individual particles. By imaging in live fish, we demonstrate that grain boundaries in the cone mosaic instead appear during initial mosaic formation, without requiring defect motion. Motivated by this observation, we show that a computational model of repulsive cell-cell interactions generates a mosaic with grain boundaries. In contrast to paradigmatic models of fate specification in mostly motionless cell packings, this finding emphasizes the role of cell motion, guided by cell-cell interactions during differentiation, in forming biological crystals. Such a route to the formation of regular patterns may be especially valuable in situations, like growth on a curved surface, where the resulting long-ranged, elastic, effective interactions between defects can help to group them into grain boundaries.
Genes / Markers
Figures
Figure Gallery (7 images)
Show all Figures
Expression
Phenotype
Fish Conditions Stage Phenotype Figure
thrbq34/q34standard conditionsAdult
1 - 1 of 1
Show
Mutations / Transgenics
Allele Construct Type Affected Genomic Region
a9
    		Complex
    b4
      		Insertion
      kj9TgTransgenic Insertion
        mi2007TgTransgenic Insertion
          mi2012TgTransgenic Insertion
            q22TgTransgenic Insertion
              q33TgTransgenic Insertion
                q34
                  		Small Deletion
                  1 - 8 of 8
                  Show
                  Human Disease / Model
                  No data available
                  Sequence Targeting Reagents
                  Target Reagent Reagent Type
                  thrbCRISPR4-thrbCRISPR
                  1 - 1 of 1
                  Show
                  Fish
                  Fish
                  thrbq34/q34
                  1 - 1 of 1
                  Show
                  Antibodies
                  Orthology
                  No data available
                  Engineered Foreign Genes
                  Marker Marker Type Name
                  CFPEFGCFP
                  EGFPEFGEGFP
                  EosEFGEos
                  mCherryEFGmCherry
                  TomatoEFGTomato
                  1 - 5 of 5
                  Show
                  Mapping
                  No data available
                  Your Input Welcome
                  We welcome your input and comments. Please use this form to recommend updates to the information in ZFIN. We appreciate as much detail as possible and references as appropriate. We will review your comments promptly.
                  Citation
                  Nunley, H., Nagashima, M., Martin, K., Lorenzo Gonzalez, A., Suzuki, S.C., Norton, D.A., Wong, R.O.L., Raymond, P.A., Lubensky, D.K. (2020) Defect patterns on the curved surface of fish retinae suggest a mechanism of cone mosaic formation. PLoS Computational Biology. 16:e1008437.