ASCL1 reprograms mouse Müller glia into neurogenic retinal progenitors

Pollak, Julia; Wilken, Matthew S.; Ueki, Yumi; Cox, Kristen E.; Sullivan, Jane; Taylor, Richard T.; Levine, Edward M.; Reh, Thomas A.

doi:10.1242/dev.091355

Cited by 220 publications

(245 citation statements)

References 67 publications

Supporting

Mentioning

224

Contrasting

Order By: Relevance

“…Activated Notch signaling and upregulation of Ascl1a are known to stimulate the formation of MGPCs in the retina (Fausett et al, 2008;Ghai et al, 2010;Hayes et al, 2007;Pollak et al, 2013). Consistent with previous reports (Hayes et al, 2007), we found increases in retinal levels of chick Delta1, Dll4, Jag (not shown), Notch1, Hes5 and Ascl1a (Fig.…”

Section: Müller Glia (Data Not Shown) By Contrast Injections Of Dex Orsupporting

confidence: 92%

Glucocorticoid receptors in the retina, Müller glia and the formation of Müller glia-derived progenitors

2014

View full text Add to dashboard Cite

Identification of the signaling pathways that influence the reprogramming of Müller glia into neurogenic retinal progenitors is key to harnessing the potential of these cells to regenerate the retina. Glucocorticoid receptor (GCR) signaling is commonly associated with anti-inflammatory responses and GCR agonists are widely used to treat inflammatory diseases of the eye, even though the cellular targets and mechanisms of action in the retina are not well understood. We find that signaling through GCR has a significant impact upon the ability of Müller glia to become proliferating Müller glia-derived progenitor cells (MGPCs). The primary amino acid sequence and pattern of GCR expression in the retina is highly conserved across vertebrate species, including chickens, mice, guinea pigs, dogs and humans. In all of these species we find GCR expressed by the Müller glia. In the chick retina, we find that GCR is expressed by progenitors in the circumferential marginal zone (CMZ) and is upregulated by Müller glia in acutely damaged retinas. Activation of GCR signaling inhibits the formation of MGPCs and antagonizes FGF2/MAPK signaling in the Müller glia. By contrast, we find that inhibition of GCR signaling stimulates the formation of proliferating MGPCs in damaged retinas, and enhances the neuronal differentiation while diminishing glial differentiation. Given the conserved expression pattern of GCR in different vertebrate retinas, we propose that the functions and mechanisms of GCR signaling are highly conserved and are mediated through the Müller glia. We conclude that GCR signaling directly inhibits the formation of MGPCs, at least in part, by interfering with FGF2/MAPK signaling.

show abstract

Section: Müller Glia (Data Not Shown) By Contrast Injections Of Dex Orsupporting

confidence: 92%

Glucocorticoid receptors in the retina, Müller glia and the formation of Müller glia-derived progenitors

2014

View full text Add to dashboard Cite

show abstract

“…One candidate for this repression, let-7, appears to inhibit regeneration in both zebrafish and Caenorhabditis elegans (14,30). Interestingly, Ascl1a inhibits let-7 expression during zebrafish MG reprogramming (14), and its overexpression in postnatal mouse MG enhanced their reprogramming (31). We suspect that this latter effect is mediated by inhibition of let-7 and hypothesize that let-7 is a key factor contributing to the limited regenerative potential of mammalian MG.…”

Section: Discussionmentioning

confidence: 93%

Analysis of DNA methylation reveals a partial reprogramming of the Müller glia genome during retina regeneration

Powell

Grant

Cornblath

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

113

138

View full text Add to dashboard Cite

Upon retinal injury, zebrafish Müller glia (MG) transition from a quiescent supportive cell to a progenitor cell (MGPC). This event is accompanied by the induction of key transcription and pluripotency factors. Because somatic cell reprogramming during induced pluripotent stem cell generation is accompanied by changes in DNA methylation, especially in pluripotency factor gene promoters, we were interested in determining whether DNA methylation changes also underlie MG reprogramming following retinal injury. Consistent with this idea, we found that genes encoding components of the DNA methylation/demethylation machinery were induced in MGPCs and that manipulating MGPC DNA methylation with 5-aza-2′-deoxycytidine altered their properties. A comprehensive analysis of the DNA methylation landscape as MG reprogram to MGPCs revealed that demethylation predominates at early times, whereas levels of de novo methylation increase at later times. We found that these changes in DNA methylation were largely independent of Apobec2 protein expression. A correlation between promoter DNA demethylation and injurydependent gene induction was noted. In contrast to induced pluripotent stem cell formation, we found that pluripotency factor gene promoters were already hypomethylated in quiescent MG and remained unchanged in MGPCs. Interestingly, these pluripotency factor promoters were also found to be hypomethylated in mouse MG. Our data identify a dynamic DNA methylation landscape as zebrafish MG transition to an MGPC and suggest that DNA methylation changes will complement other regulatory mechanisms to ensure gene expression programs controlling MG reprogramming are appropriately activated during retina regeneration.repair | multipotent | Ascl1 | bisulfite sequencing | DNA sequencing I nduced pluripotent stem cells (iPSCs) can be generated through the forced expression of pluripotency factor genes, such as Oct4, Klf4, Sox2, c-Myc, Lin28, and Nanog, which are normally expressed in embryonic stem cells (ESCs) (1, 2). Pluripotency factor gene expression in ESCs and iPSCs is associated with chromatin that is in an "open" accessible state, whereas their repression in somatic cells is associated with less accessible, condensed chromatin (3). DNA methylation has a significant impact on chromatin structure (3). DNA demethylation of pluripotency factor promoter regions is correlated with increased expression during iPSC formation (4, 5). Similar epigenetic changes are seen in other cellular reprogramming events such as nuclear transfer (6), heterokaryon formation (7), and carcinogenesis (8).Tissue regeneration provides another avenue to study cellular reprogramming. Unlike mammals, zebrafish can regenerate multiple tissues, including the retina. During zebrafish retina regeneration, Müller glia (MG) reprogram to generate progenitor cells (MGPCs) capable of replacing all lost neural cell types (9-12). The role that MG play during this regenerative event can be roughly divided into three phases: the replication-independent transition of MG to...

show abstract

“…S4). Proneural/retinal markers NEU-ROD1, responsible for the development of PRs and amacrines [48], and ASCL1 (MASH1) [49], which determine competence-restricted progenitor lineage in the retina [50], demonstrated very high expression reaching a peak at 4 weeks (377.3 -5.5 and 134.2 -12.5, respectively). The CHX10 marker of multipotential retinal progenitors and bipolar cell fate [51,52] Table S3).…”

Section: Resultsmentioning

confidence: 99%

Characterization of Three-Dimensional Retinal Tissue Derived from Human Embryonic Stem Cells in Adherent Monolayer Cultures

Singh

Mallela

Cornuet

et al. 2015

Stem Cells and Development

View full text Add to dashboard Cite

Stem cell-based therapy of retinal degenerative conditions is a promising modality to treat blindness, but requires new strategies to improve the number of functionally integrating cells. Grafting semidifferentiated retinal tissue rather than progenitors allows preservation of tissue structure and connectivity in retinal grafts, mandatory for vision restoration. Using human embryonic stem cells (hESCs), we derived retinal tissue growing in adherent conditions consisting of conjoined neural retina and retinal pigment epithelial (RPE) cells and evaluated cell fate determination and maturation in this tissue. We found that deriving such tissue in adherent conditions robustly induces all eye field genes (RX, PAX6, LHX2, SIX3, SIX6) and produces four layers of pure populations of retinal cells: RPE (expressing NHERF1, EZRIN, RPE65, DCT, TYR, TYRP, MITF, PMEL), early photoreceptors (PRs) (coexpressing CRX and RCVRN), inner nuclear layer neurons (expressing CALB2), and retinal ganglion cells [RGCs, expressing BRN3B and Neurofilament (NF) 200]. Furthermore, we found that retinal progenitors divide at the apical side of the hESC-derived retinal tissue (next to the RPE layer) and then migrate toward the basal side, similar to that found during embryonic retinogenesis. We detected synaptogenesis in hESC-derived retinal tissue, and found neurons containing many synaptophysin-positive boutons within the RGC and PR layers. We also observed long NF200-positive axons projected by RGCs toward the apical side. Whole-cell recordings demonstrated that putative amacrine and/or ganglion cells exhibited electrophysiological responses reminiscent of those in normal retinal neurons. These responses included voltagegated Na + and K + currents, depolarization-induced spiking, and responses to neurotransmitter receptor agonists. Differentiation in adherent conditions allows generation of long and flexible pieces of 3D retinal tissue suitable for isolating transplantable slices of tissue for retinal replacement therapies.

show abstract

ASCL1 reprograms mouse Müller glia into neurogenic retinal progenitors

Cited by 220 publications

References 67 publications

Glucocorticoid receptors in the retina, Müller glia and the formation of Müller glia-derived progenitors

Glucocorticoid receptors in the retina, Müller glia and the formation of Müller glia-derived progenitors

Analysis of DNA methylation reveals a partial reprogramming of the Müller glia genome during retina regeneration

Characterization of Three-Dimensional Retinal Tissue Derived from Human Embryonic Stem Cells in Adherent Monolayer Cultures

Contact Info

Product

Resources

About