Introduction

The neural retina, the light-sensitive part of the eye, converts light into electrical signals that are relayed to visual centers in the brain. The retina is part of the central nervous system (CNS), originating from the neural ectoderm during development. In vertebrates, the retina begins as an apparently homogeneous collection of cells in a single-layered neuroepithelium. With maturation, however, it develops into a laminated tissue with seven major cell classes, each of which occupies characteristic positions within the retina. The structural and functional development of the retina has long been studied because of its importance in vision, and because its highly organized structure is ideally suited for studying cell fate, differentiation, and patterning of synaptic networks in the nervous system.