Biology subjects

Jadali, A.

Publications and source records attributed to Jadali, A..

4 recordsLinked to original sources

bioRxiv2025

CHD7 binds distinct regions in the Sox11 locus to regulate neuronal differentiation

The chromodomain helicase DNA binding protein 7 (CHD7) is a nucleosome repositioner implicated in multiple cellular processes, including neuronal differentiation. We identified CHD7 genome-wide binding sites that regulate neuronal differentiation in an otic stem cell line. We identified CHD7 enrichment at the Sox11 promoter and 3 untranslated region (UTR). Sox11 is a transcription factor essential for neuronal differentiation. CRISPRi of Sox11 promoter or 3UTR displayed decreased neurite lengths and reduced neuronal marker expression TUBB3 expression. We showed that the Sox11 locus resides at TAD boundaries, and CTCF marks the 3UTR. We propose that CHD7 modulates chromatin accessibility of the Sox11 promoter and CTCF-marked insulators in the 3UTR to facilitate neuronal differentiation. CRISPRi of the insulator site alters 3D chromatin organization, affects gene expression and ultimately perturbs cellular processes. Our results implicate a general mechanism of CHD7 in facilitating neuronal differentiation and provide insight into CHD7 dysfunction in CHARGE syndrome, a congenital disorder associated with hearing loss.

molecular biology↗

bioRxiv2025

CHD7 binds to insulators during neuronal differentiation

Spiral ganglion neurons (SGNs) are crucial for hearing, and the loss of SGNs causes hearing loss. Stem cell-based therapies offer a promising approach for SGN regeneration and require understanding the mechanisms governing SGN differentiation. We investigated the chromatin remodeler CHD7 in neuronal differentiation using immortalized multipotent otic progenitor (iMOP) cells. We demonstrated that CHD7 knockdown impaired neuronal differentiation. Genome-wide analysis revealed CHD7 binding at diverse cis-regulatory elements, with notable enrichment at sites marked by the insulator-binding protein CTCF between topologically associating domains (TADs). Insulators marked by the enrichment of CHD7 and CTCF resided near genes critical for neuronal differentiation, including Mir9-2. Targeting these regulatory regions in iMOPs with CRISPR interference (CRISPRi) and activation (CRISPRa) increased miR-9 transcription, irrespective of the method. Blocking the CHD7 and CTCF marked sites suggested that the elements function as insulators to regulate gene expression. The study highlights CHD7 activity at insulators and underscores an unreported mechanism for promoting neuronal differentiation.

molecular biology↗

bioRxiv2022

Alcohol reverses the effects of KCNJ6 (GIRK2) noncoding variants on excitability of human glutamatergic neurons

Synonymous and noncoding single nucleotide polymorphisms (SNPs) in the KCNJ6 gene, encoding G protein-gated inwardly rectifying potassium (GIRK2) channel subunit 2, have been linked with increased electroencephalographic frontal theta event-related oscillations (ERO) in subjects diagnosed with alcohol use disorder (AUD). To identify molecular and cellular mechanisms while retaining the appropriate genetic background, we generated induced excitatory glutamatergic neurons (iN) from iPSCs derived from four AUD-diagnosed subjects with KCNJ6 variants ( Affected: AF) and four control subjects without variants ( Unaffected: UN). Neurons were analyzed for changes in gene expression, morphology, excitability and physiological properties. Single cell RNA sequencing suggests that KCNJ6 AF variant neurons have altered patterns of synaptic transmission and cell projection morphogenesis. Results confirm that AF neurons express lower levels of GIRK2, have greater neurite area, and elevated excitability. Interestingly, exposure to intoxicating concentrations of ethanol induces GIRK2 expression and reverses functional effects in AF neurons. Ectopic overexpression of GIRK2 alone mimics the effect of ethanol to normalize induced excitability. We conclude that KCNJ6 variants decrease GIRK2 expression and increase excitability and that this effect can be minimized or reduced with ethanol.

neuroscience↗

bioRxiv2021

Analyses of the Autism-associated Neuroligin-3 R451C Mutation in Human Neurons Reveals a Gain-of-Function Synaptic Mechanism

Mutations in many synaptic genes are associated with autism spectrum disorders (ASDs), suggesting that synaptic dysfunction is a key driver of ASD pathogenesis. Among these mutations, the R451C-substitution in the NLGN3 gene that encodes the postsynaptic adhesion molecule Neuroligin-3 is noteworthy because it was the first specific mutation linked to ASDs. In mice, the corresponding Nlgn3 R451C-knockin mutation recapitulates social interaction deficits of ASD patients and produces synaptic abnormalities, but the impact of the NLGN3 R451C-mutation on human neurons has not been investigated. Here, we generated human knock-in neurons with the NLGN3 R451C-mutation. Strikingly, analyses of NLGN3 R451C-mutant neurons revealed that the R451C-mutation decreased NLGN3 protein levels but enhanced the strength of excitatory synapses without affecting inhibitory synapses. No significant cell death and endoplasmic reticulum stress were detected. Importantly, the augmentation of excitatory transmission was confirmed in vivo with human neurons transplanted into mouse forebrain. Using single-cell RNA-seq experiments with co-cultured excitatory and inhibitory NLGN3 R451C-mutant neurons, we identified differentially expressed genes in relatively mature human neurons that corresponded to synaptic gene expression networks. Moreover, gene ontology and enrichment analyses revealed convergent gene networks associated with ASDs and other mental disorders. Our findings suggest that the NLGN3 R451C-mutation induces a gain-of-function enhancement in excitatory synaptic transmission that may contribute to the pathophysiology of ASDs.

neuroscience↗