Retinal Transdifferentiation Induced by NeuroD on Retinal Pigmented Epithelial Cells

Abstract

The receptors for light in the vertebrate eye are photoreceptors of the retina. Photoreceptors are a group of light-sensitive receptor neurons which are terminal differentiated that do not divide and are not replaced if destroyed. The degenerative diseases of photoreceptors is a common cause of losing sight in retina. One of the treatment for retinal regeneration is to re-supply the type of cells that were damaged with neural progenitor cells or stem cells. The retinal pigmented epithelium (RPE) is the pigmented cell layer lies adjacent to photoreceptors that can reenter the cell cycle under certain trigger. This makes RPE as one of the stem cell sources to differentiate into neural progenitor cells or retinal precursor cells. In chick retina, the determination of the photoreceptor cell's fate may involve NeuroD, which is homologous to the drosophila proneural gene atonal. In addition, an overproduction of photoreceptor cells in the developing chick retina under retrovirus-driven NeuroD expression. In this study, The NeuroD gene was transfected into the RPE cells and some of the cells showed immunoreactivity for rhodopsin. The results demonstrate that RPE cells can be directed to photoreceptor fate and thus may be useful in the treatment of retinal degenerative diseases.