XB-ART-38648Semin Cell Dev Biol July 1, 2009; 20 (5): 528-34.
Anuran amphibians can regenerate the retina through differentiation of stem cells in the ciliary marginal zone and through transdifferentiation of the retinal pigmented epithelium. By contrast, the regeneration of the lens has been demonstrated only in larvae of species belonging to the Xenopus genus, where the lens regenerates through transdifferentiation of the outer cornea. Retinal pigmented epithelium to neural retina and outer cornea to lens transdifferentiation processes are triggered and sustained by signaling molecules belonging to the family of the fibroblast growth factor. Both during retina and lens regeneration there is a re-activation of many of the genes which are activated during development of the eye, even though the spatial and temporal pattern of gene expression is not a simple repetition of that found in development.
PubMed ID: 19095070
Article link: Semin Cell Dev Biol
Genes referenced: pax6 rpe
Article Images: [+] show captions
|Fig. 1. On the top, scheme of implantation of a RPE fragment into the vitreous chamber of a host eye (the lens was first removed and then re-inserted into the pupil). (A–C) Progressive depigmentation and Pax6 expression in the part of the implant facing the host retina. In situ hybridization using a digoxigenin-labelled anti-sense pax6 RNA probe. (A) 15 days after operation, Pax6 expression is observed in all depigmenting cells of the implant. (B) 20 days after operation, the intensity of Pax6 expression is decreasing in the presumptive ONL (asterisked). (C) 30 days after operation, Pax6 expression is confined to GCL and INL. ONL (asterisked) does not express Pax6. Immunoreaction with a monoclonal antibody anti-IPM (interphotoreceptor matrix) and horseradish peroxidase-conjugated goat anti-mouse (3-amino-ethylcarbazol as substrate). The photoreceptor layers of the new-formed and the host retina are red. The part of the implant facing the host lens had conserved the RPE phenotype. hl, host lens; hr, host retina; nr, new-forming retina. Bars: A–C, 25 μm; C, 100 μm. Figure from Arresta et al. , modified.|