Angelman syndrome-derived neurons display late onset of paternal UBE3A silencing

Abstract

Genomic imprinting is an epigenetic phenomenon resulting in parent-of-origin-specific gene expression that is regulated by a differentially methylated region. Gene mutations or failures in the imprinting process lead to the development of imprinting disorders, such as Angelman syndrome. The symptoms of Angelman syndrome are caused by the absence of functional UBE3A protein in neurons of the brain. To create a human neuronal model for Angelman syndrome, we reprogrammed dermal fibroblasts of a patient carrying a defined three-base pair deletion in UBE3A into induced pluripotent stem cells (iPSCs). In these iPSCs, both parental alleles are present, distinguishable by the mutation, and express UBE3A. Detailed characterization of these iPSCs demonstrated their pluripotency and exceptional stability of the differentially methylated region regulating imprinted UBE3A expression. We observed strong induction of SNHG14 and silencing of paternal UBE3A expression only late during neuronal differentiation, in vitro. This new Angelman syndrome iPSC line allows to study imprinted gene regulation on both parental alleles and to dissect molecular pathways affected by the absence of UBE3A protein.

In Vitro Generation of Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature from Murine Induced Pluripotent Stem Cells

“…Vector particle production (see Supplemental Experimental Procedures) was performed as previously described (Stanurova et al., 2016). Primary fibroblasts were cultured up to 80% confluence.…”

Human cerebral organoids capture the spatiotemporal complexity and disease dynamics of UBE3A

“…The silencing of paternal UBE3A is also associated with a long, non-coding antisense RNA (UBE3A-ATS). As cells differentiate into neurons, UBE3A-ATS expression increases to a high enough level to silence paternal UBE3A, potentially through a hypothesized collision mechanism (Hsiao et al, 2019;Stanurova et al, 2016) between these two opposed and overlapping transcripts.…”

“…However, at 4 weeks, we observed only a reduction in UBE3A-ATS and did not detect an increase in UBE3A expression ( Figure 4D). This could be attributed to a delay between transcription of UBE3A-ATS and silencing of UBE3A (Hsiao et al, 2019;Stanurova et al, 2016) (Figures 3A and 3B) so that UBE3A expression levels are still high at that stage of hCO development.…”

Progress in the molecular mechanisms of genetic epilepsies using patient‐induced pluripotent stem cells

“…However, hypermethylation has not been obvious in iPSC studies . Changes in the UBE3A gene affect the functional maturation of neurons, and the appearance of AMPA receptor–mediated excitatory postsynaptic currents (EPSCs) in patient‐derived neurons is significantly delayed . In the late stage of neuronal development and maturation, the resting membrane potential exhibits depolarization, decreased spontaneous excitatory postsynaptic action potentials, decreased neuron activity, and decreased synaptic plasticity.…”

“…86,87 Changes in the UBE3A gene affect the functional maturation of neurons, and the appearance of AMPA receptor-mediated excitatory postsynaptic currents (EPSCs) in patient-derived neurons is significantly delayed. 88 In the late stage of neuronal development and maturation, the resting membrane potential exhibits depolarization, decreased spontaneous excitatory postsynaptic action potentials, decreased neuron activity, and decreased synaptic plasticity. In combination with the CRISPR/Cas9 gene-editing technique, it was demonstrated that the depolarization of the resting membrane potential induced by the UBE3A mutation might be an important cause of altered cell activity.…”