A conserved role of αA-crystallin in the development of the zebrafish embryonic lens

Zou, P., Wu, S.Y., Koteiche, H.A., Mishra, S., Levic, D.S., Knapik, E., Chen, W., Mchaourab, H.S.
Experimental Eye Research   138: 104-13 (Journal)
Registered Authors
Chen, Wenbiao, Knapik, Ela W., Wu, Shu-Yu (Simon)
Alpha-crystallin, TALEN, cataract, chaperone, lens development, maternal transcript, morpholino, small heat shock protein, zebrafish
MeSH Terms
  • Animals
  • Animals, Genetically Modified
  • Blotting, Western
  • Electrophoresis, Polyacrylamide Gel
  • Embryo, Nonmammalian/physiology*
  • Gene Expression Regulation, Developmental/physiology*
  • Gene Knockout Techniques
  • Lens, Crystalline/embryology*
  • Real-Time Polymerase Chain Reaction
  • Zebrafish/embryology*
  • alpha-Crystallin A Chain/physiology*
26149094 Full text @ Exp. Eye. Res.
αA- and αB-crystallins are small heat shock proteins that bind thermodynamically destabilized proteins thereby inhibiting their aggregation. Highly expressed in the mammalian lens, the α-crystallins have been postulated to play a critical role in the maintenance of lens optical properties by sequestering age-damaged proteins prone to aggregation as well as through a multitude of roles in lens epithelial cells. Here, we have examined the role of α-crystallins in the development of the vertebrate zebrafish lens. For this purpose, we have carried out morpholino-mediated knockdown of αA-, αBa- and αBb-crystallin and characterized the gross morphology of the lens. We observed lens abnormalities, including increased reflectance intensity, as a consequence of the interference with expression of these proteins. These abnormalities were less frequent in transgenic zebrafish embryos expressing rat αA-crystallin suggesting a specific role of α-crystallins in embryonic lens development. To extend and confirm these findings, we generated an αA-crystallin knockout zebrafish line. A more consistent and severe lens phenotype was evident in maternal/zygotic αA-crystallin mutants compared to those observed by morpholino knockdown. The penetrance of the lens phenotype was reduced by transgenic expression of rat αA-crystallin and its severity was attenuated by maternal αA-crystallin expression. These findings demonstrate that the role of α-crystallins in lens development is conserved from mammals to zebrafish and set the stage for using the embryonic lens as a model system to test mechanistic aspects of α-crystallin chaperone activity and to develop strategies to fine-tune protein-protein interactions in aging and cataracts.
Genes / Markers
Mutation and Transgenics
Human Disease / Model Data
Sequence Targeting Reagents
Engineered Foreign Genes
Errata and Notes