Abstract
Purpose: :
Proper visual function of the vertebrate retina requires the maintenance of the integrity of the retinal outer nuclear layer (ONL), which is often affected in many blinding human retinal diseases. While the structural integrity of the ONL has long been considered to be maintained primarily through the outer limiting membrane (OLM), we have little knowledge on the development and maintenance of the OLM itself. In this study we perform analysis to determine the role of the nok gene in photoreceptor adhesion.
Methods: :
Immunohistochemical analyses were performed to determine the adhesion property of photoreceptors in wildtype, nok mutant, and N–cad mutant retinas. Blastomere transplantation experiments were also performed to analyze the mobility of photoreceptors in the retina.
Results: :
We demonstrated that the nok gene is essential for the establishment and/or maintenance of the OLM. In addition, our results imply the possibility that Nok and its associated proteins may constitute a type of photoreceptor–photoreceptor junctional complex that has not been described before.
Conclusions: :
Our study provides novel insights into the mechanisms by which the integrity of the ONL is maintained in the vertebrate retina. The results also form the basis for further investigation to elucidate the molecular mechanisms by which Nok functions in photoreceptor adhesion.
Keywords: retinal development • photoreceptors