A comparative analysis of Müller glia-mediated regeneration in the vertebrate retina

•We review the potential of Müller glia to become retinal progenitor cells.•We compare and contrast Müller glia-derived progenitors in the fish, birds and mammals.•We discuss the factors and signaling pathways that influence Müller glia-derived progenitors.•We discuss the continuum of phenotypes and functions that lies between progenitors and Müller glia.

This article reviews the current state of knowledge regarding the potential of Müller glia to become neuronal progenitor cells in the avian retina. We compare and contrast the remarkable proliferative and neurogenic capacity of Müller glia in the fish retina to the limited capacity of Müller glia in avian and rodent retinas. We summarize recent findings regarding the secreted factors, signaling pathways and cell intrinsic factors that have been implicated in the formation of Müller glia-derived progenitors. We discuss several key similarities and differences between the fish, rodent and chick model systems, highlighting several of the key transcription factors and signaling pathways that regulate the formation of Müller glia-derived progenitors.