Linking YAP to Müller Glia Quiescence Exit in the Degenerative Retina

Area of Science:

• Neuroscience
• Regenerative Medicine
• Cell Biology

Background:

• Mammalian retinal regeneration from Müller glial cells is limited compared to fish and amphibians.
• Müller glial cells are neural stem cells in the retina, but their regenerative potential is largely quiescent in adult mammals.

Purpose of the Study:

• To investigate the role of the Hippo pathway effector YAP (Yes-associated protein) in Müller glial cell proliferation and retinal regeneration.
• To identify molecular cues that can enhance the stemness potential of mammalian Müller glial cells.

Main Methods:

• Conditional Yap deletion in mouse Müller cells.
• Analysis of cell-cycle gene expression following photoreceptor cell death in mice.
• Investigating YAP's role in Xenopus retinal injury response.
• Inducing Müller cell proliferation via YAP overactivation in mouse retinas.

Main Results:

• Conditional Yap deletion in mice prevented cell-cycle gene upregulation in Müller cells after injury.
• YAP is essential for the proliferative response of Xenopus Müller cells to injury.
• YAP overactivation in mouse Müller cells induced reprogramming into highly proliferative cells.
• A YAP-EGFR (epidermal growth factor receptor) axis was identified, mediating Müller cell quiescence exit.

Conclusions:

• YAP plays a pivotal role in regulating Müller cell proliferation in response to retinal injury.
• Targeting the YAP-EGFR axis could be a strategy to promote retinal regeneration in mammals.