The α1 isoform of the Na+/K+ ATPase is up-regulated in dedifferentiated progenitor cells that mediate lens and retina regeneration in adult newts

Abstract

Adult newts are able to regenerate their retina and lens after injury or complete removal through transdifferentiation of the pigmented epithelial tissues of the eye. This process needs to be tightly controlled, and several different mechanisms are likely to be recruited for this function. The Na + / K + ATPase is a transmembrane protein that establishes electrochemical gradients through the transport of Na + and K + and has been implicated in the modulation of key cellular processes such as cell division, migration and adhesion. Even though it is expressed in all cells, its isoform composition varies with cell type and is tightly controlled during development and regeneration. In the present study we characterize the expression pattern of Na + /K + ATPase α1 in the adult newt eye and during the process of lens and retina regeneration. We show that this isoform is up-regulated in undifferentiated cells during transdifferentiation. Such change in composition could be one of the mechanisms that newt cells utilize to modulate this process.

Seeing the future: using Xenopus to understand eye regeneration

“…FGF‐dependent neural regeneration activated the MAPK pathway. Furthermore, inhibition of a downstream transducer, MEK, blocks FGF‐dependent retinal regeneration (Vergara & Del Rio‐Tsonis, ). As the CMZ was ablated in this model, the likely source of progenitor cell population is the RPE.…”

“…Another model of retinal regeneration was developed by Vergara and Del‐Rio Tsonis, which used a new surgical approach where retinectomy also removed the CMZ. In this case, retinal regeneration only occurred in the presence of FGF induction using FGF2‐soaked beads as a growth factor source (Vergara & Del Rio‐Tsonis, ). FGF‐dependent neural regeneration activated the MAPK pathway.…”

“…In addition, methods exist in Xenopus for assessing the efficacy of localized drug delivery. For example, beads carrying FGF2 induced tadpole retinal regeneration (Vergara & Del Rio‐Tsonis, ). More recently, it was shown that injected magnetic nanoparticles localized to the tadpole RPE and are retained for several days (Giannaccini et al, ).…”

The Effects of Different Culture Media on Human Corneal Endothelial Cells

“…It has been reported that the a1 isoform of the Naþ/Kþ ATPase is upregulated in dedifferentiated progenitor cells. 27 Further study is necessary to investigate the mechanism of increased Na þ -K þ ATPase and COL8A2 expression. Proliferation rates were different depending on the medium used.…”

Lens and retina regeneration: new perspectives from model organisms

“…Na + channels have been used to monitor ganglion cell differentiation during RPE transdifferentiation [129,130,139]. In contrast, a study by Vergara et al [140] reported that the α subunit of the Na + /K + -ATPase is up-regulated transiently in the RPE during early transdifferentiation when retinal progenitors form, but is not present in the intact RPE or neural retina. It must be noted that more research is required to elucidate further the role of these channels/transporters during retina regeneration.…”