Disrupted neuronal maturation in Angelman syndrome-derived induced pluripotent stem cells

Abstract

Angelman syndrome (AS) is a neurogenetic disorder caused by deletion of the maternally inherited UBE3A allele and is characterized by developmental delay, intellectual disability, ataxia, seizures and a happy affect. Here, we explored the underlying pathophysiology using induced pluripotent stem cell-derived neurons from AS patients and unaffected controls. AS-derived neurons showed impaired maturation of resting membrane potential and action potential firing, decreased synaptic activity and reduced synaptic plasticity. These patient-specific differences were mimicked by knocking out UBE3A using CRISPR/Cas9 or by knocking down UBE3A using antisense oligonucleotides. Importantly, these phenotypes could be rescued by pharmacologically unsilencing paternal UBE3A expression. Moreover, selective effects of UBE3A disruption at late stages of in vitro development suggest that changes in action potential firing and synaptic activity may be secondary to altered resting membrane potential. Our findings provide a cellular phenotype for investigating pathogenic mechanisms underlying AS and identifying novel therapeutic strategies.

Genome editing for understanding and improving the brain

“…Another CRISPR approach to understand genotype‐phenotype relationships is to introduce specific mutations. For example, an edited cell line with disrupted Angelman syndrome UBE3A gene showed impaired neuronal maturation and replicated the cellular phenotype observed in stem cell‐derived neurones from patients with Angelman syndrome …”

“…For example, an edited cell line with disrupted Angelman syndrome UBE3A gene showed impaired neuronal maturation and replicated the cellular phenotype observed in stem cell-derived neurones from patients with Angelman syndrome. 5 Beyond technical issues, a number of bioethical aspects must still be addressed. Yet, among many obstacles that remain before genome editing becomes a viable treatment for neurodevelopmental disorders, the main one may be our current lack of understanding of human neural function.…”

Molecular correlates of topiramate andGRIK1rs2832407 genotype in pluripotent stem cell-derived neural cultures

“…Whole cell patch-clamp electrophysiology was performed on neurons differentiated from rs2832407 A/A and C/C iPSCs using previously described techniques (Lemtiri-Chlieh and Levine, 2010; Fink et al, 2017). Neurons were selected for recording based on morphology, including pyramidal-shaped soma and the presence of neurites.…”

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

“…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 . Chen et al explored the underlying pathophysiology using iPSC‐derived neurons from patients with Angelman syndrome and unaffected controls and found that the long noncoding RNAs (lncRNAs) RNA‐binding protein fox‐1 homolog (RBFOX1) and RBFOX2 were downregulated in Angelman syndrome neurons.…”

“…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. 89 Chen et al 90 explored the underlying pathophysiology using iPSCderived neurons from patients with Angelman syndrome and unaffected controls and found that the long noncoding RNAs (lncRNAs) RNA-binding protein fox-1 homolog (RBFOX1) and RBFOX2 were downregulated in Angelman syndrome neurons. When UBE3A was overexpressed, the differentiation abnormalities in the immature cells were rescued.…”