Effect of Sugars on Photoreceptor Outer Segment Assembly

Abstract

During embryonic development, the rudimentary layers that will become the pigment epithelium (PE) and the neural retina are brought into close proximity upon the collapse of the optic vesicles. At this developmental stage, the retina is morphologically undifferentiated and photoreceptor outer segments have not yet begun to form. The close apposition of the PE and photoreceptors prior to the time when outer segments first appear raises the possibility that the PE could be a source of signals that induce or regulate photoreceptor development and outer segment elaboration. Also, the observation that outer segment development is limited in the absence of the PE in most species suggests that interactions between these two cell types may be of fundamental importance for the structural and functional maturation of photoreceptors [1, 2, 3, 5, 13, 16, 19, 20, 26].