Figure 11.

Summary diagram of cone regeneration. (a) Müller glia respond to photoreceptor death by expressing mmp‐9, undergoing interkinetic nuclear migration and a single asymmetric cell division that gives rise to a neuronal progenitor. (b) In wild‐type animals, neuronal progenitors form a neurogenic cluster around the Müller glia (3 dpl), migrate to the ONL, and differentiate into cone photoreceptors (7 dpl) that then mature (21 dpl). (c) Anti‐inflammatory treatment results in fewer Müller glia‐derived progenitors and fewer regenerated photoreceptors. (d) In the absence of Mmp‐9, there is overproduction of Müller glia‐derived progenitors and regenerating photoreceptors. However, at 21 dpl, survival of cone photoreceptors is compromised. (e) In the absence of Mmp‐9, anti‐inflammatory treatment rescues the defects of cone photoreceptors. GCL, ganglion cell layer; INL, inner nuclear layer; ONL, outer nuclear layer [Color figure can be viewed at wileyonlinelibrary.com]