Dataset Information

MicroRNA profile of extracellular vesicles released by Müller glial cells

ABSTRACT: As any other radial glia in the central nervous system, Müller glia derive from the same neuroepithelial precursors, perform similar functions and exhibit neurogenic properties as radial glia in the brain. Müller glial cells retain progenitor-like characteristics in the adult human eye, and can partially restore visual function upon intravitreal transplantation into animal models of glaucoma. Recently, it has been demonstrated that intracellular communication is possible via the secretion of nano-sized membrane-bound extracellular vesicles (EV), which contain bioactive molecules like microRNA (miRNA) and proteins that induce phenotypic changes when internalised by recipient cells. We conducted high-throughput sequencing to profile the microRNA signature of EV populations secreted by Müller glia in culture, and used bioinformatic tools to evaluate their potential role in the neuroprotective signalling attributed to these cells. Sequencing of miRNA within Müller EV suggested enrichment with species associated with stem cells such as miR-21 and miR-16, as well as with miRNA previously found to play a role in diverse Müller cell functions in the retina: miR-9, miR-125b and the let-7 family. A total of 51 miRNA were found to be differentially enriched in EV compared to whole cells from which EV originated. Bioinformatic analyses also indicated preferential enrichment of species demonstrated to regulate genes involved in cell proliferation and survival, including PTEN the master inhibitor of the PI3K/AKT pathway. The results suggest that the release by Müller cells of miRNA-enriched EV abundant in species that regulate anti-apoptotic signalling networks, is likely to represent a significant proportion of the neuroprotective effect observed after transplantation of these cells into animal models of retinal ganglion cell (RGC)-depletion. Future work will seek to evaluate the modulation of putative genes, as well as the activation of these pathways in in vitro and in vivo models following the internalisation of Müller-EV by target retinal neurons.

ORGANISM(S): Homo sapiens

PROVIDER: GSE245286 | GEO | 2024/01/03

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Loss of neurons in the neural retina is a leading cause of vision loss. Retinal regeneration in zebrafish is attributed to Müller glia, which are activated, adopt a stem cell-like state, proliferate, and generate new neurons. Despite the same endogenous Müller glia being present in all vertebrates including humans, Müller glia activation in mammals leads to glial scarring instead of neurogenesis. Therefore, understanding Müller glia cellular states and molecular processes during zebrafish regeneration may allow us to improve mammalian regeneration. Since only a subset of Müller glia activate following neuron loss, we asked whether a specialised subset of Müller glia might be genetically primed for activation. Single-cell RNA sequencing (sc-RNAseq) from integrated zebrafish Müller glia samples reveals heterogeneity of gene expression across the quiescent Müller glia pool with 4 main clusters emerging, two of which are genetically similar. Labelling for key differentially expressed markers identified that these main clusters correlated with glia spatially distributed across dorsal, central and ventral retina. Using a genetically driven, chemically induced nitroreductase approach, three distinct photoreceptor types were ablated: the long (Lws2), short wavelength-sensitive (Sws2) and rod (Xops) photoreceptors, which also differ in their abundance. As expected, histological analysis of the three injuries and sc-RNAseq data for the two cone photoreceptor ablations identified common genetic program involved in the transition of Müller glia quiescence to activation, and differential responses to injury related to either injury extent or subtype of photoreceptor targeted. Interestingly, despite differences in the distributed across the retina, biased activation of Müller glia was observed in dorsal and central regions. Gene ontology analysis revealed that these injury-responsive dorsal and central Müller glia express genes related to dorsal/ventral pattern formation, growth factor activity, and regulation of developmental process. Müller glia upregulated genes related to homeostasis as well as certain AP-1 and injury-responsive transcription factors, followed by expression of genes involved in cell cycle, chromatin remodeling, and microtubule organisation. Prior to cell cycle entry, Müller glia show a transient upregulation of genes involved in gliogenesis, and Notch signalling. These findings enhance our understanding of heterogeneous states of quiescent Müller glia, and how these differences relate to activation and regeneration potential following neural ablation. A comparison of the distinct quiescent Müller glia with glia states in mammals will reveal key molecular pathways that could be targeted for improved mammalian neural regeneration.

Dataset Information

MicroRNA profile of extracellular vesicles released by Müller glial cells

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure