Dataset Information

Transcriptional Dysregulation and Impaired Neuronal Activity in FMR1 Knock-Out and Fragile X Patients' iPSC-Derived Models.

ABSTRACT: Fragile X syndrome (FXS) is caused by a repression of the FMR1 gene that codes the Fragile X mental retardation protein (FMRP), an RNA binding protein involved in processes that are crucial for proper brain development. To better understand the consequences of the absence of FMRP, we analyzed gene expression profiles and activities of cortical neural progenitor cells (NPCs) and neurons obtained from FXS patients' induced pluripotent stem cells (IPSCs) and IPSC-derived cells from FMR1 knock-out engineered using CRISPR-CAS9 technology. Multielectrode array recordings revealed in FMR1 KO and FXS patient cells, decreased mean firing rates; activities blocked by tetrodotoxin application. Increased expression of presynaptic mRNA and transcription factors involved in the forebrain specification and decreased levels of mRNA coding AMPA and NMDA subunits were observed using RNA sequencing on FMR1 KO neurons and validated using quantitative PCR in both models. Intriguingly, 40% of the differentially expressed genes were commonly deregulated between NPCs and differentiating neurons with significant enrichments in FMRP targets and autism-related genes found amongst downregulated genes. Our findings suggest that the absence of FMRP affects transcriptional profiles since the NPC stage, and leads to impaired activity and neuronal differentiation over time, which illustrates the critical role of FMRP protein in neuronal development.

SUBMITTER: Maussion G

PROVIDER: S-EPMC10573568 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Transcriptional Dysregulation and Impaired Neuronal Activity in <i>FMR1</i> Knock-Out and Fragile X Patients' iPSC-Derived Models.

Maussion Gilles G Rocha Cecilia C Abdian Narges N Yang Dimitri D Turk Julien J Carrillo Valenzuela Dulce D Pimentel Luisa L You Zhipeng Z Morquette Barbara B Nicouleau Michael M Deneault Eric E Higgins Samuel S Chen Carol X-Q CX Reintsch Wolfgang E WE Ho Stanley S Soubannier Vincent V Lépine Sarah S Modrusan Zora Z Lund Jessica J Stephenson William W Schubert Rajib R Durcan Thomas M TM

International journal of molecular sciences 20231005 19

Fragile X syndrome (FXS) is caused by a repression of the <i>FMR1</i> gene that codes the Fragile X mental retardation protein (FMRP), an RNA binding protein involved in processes that are crucial for proper brain development. To better understand the consequences of the absence of FMRP, we analyzed gene expression profiles and activities of cortical neural progenitor cells (NPCs) and neurons obtained from FXS patients' induced pluripotent stem cells (IPSCs) and IPSC-derived cells from FMR1 knoc ...[more]

PMID: 37834379

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Dataset Information

Transcriptional Dysregulation and Impaired Neuronal Activity in FMR1 Knock-Out and Fragile X Patients' iPSC-Derived Models.

Publications

Transcriptional Dysregulation and Impaired Neuronal Activity in <i>FMR1</i> Knock-Out and Fragile X Patients' iPSC-Derived Models.

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