Directed differentiation of human pluripotent stem cells into cortical interneurons
Ontology highlight
ABSTRACT: Here we demonstrate the highly efficient derivation of human cortical interneurons in a NKX2.1::GFP hESC reporter line. Manipulating the timing of SHH activation yields three distinct GFP+ populations with specific transcriptional profiles, neurotransmitter phenotypes and migratory behaviors.
Project description:Here we demonstrate the highly efficient derivation of human cortical interneurons in a NKX2.1::GFP hESC reporter line. Manipulating the timing of SHH activation yields three distinct GFP+ populations with specific transcriptional profiles, neurotransmitter phenotypes and migratory behaviors. Total RNA was isolated at day 18 of differentiation from FACS sorted NKX2.1::GFP+ cells from three varying differentiation conditions and a “No SHH” condition (no sonic hedgehog treatment) that did not contain any GFP-expressing cells (Trizol, Sigma). Samples for each group in triplicate were processed for Illumina bead arrays (Illumina HT-12) by the MSKCC genomics core facility according to the specifications of the manufacturer.
Project description:Unilateral Traumatic Brain Injury (TBI) causes functional disturbances of the neuronal networks spreading even to the undamaged cortical hemisphere. The phenomenon, referred to as transhemispheric diaschisis, is suggested to be mediated by an imbalance of the strength of glutamatergic, excitatory vs. GABAergic, inhibitory neurotransmission. Here we present evidence that a switch in expression of α Subunits of pore-forming L-Type voltage-gated calcium channels (VGCC), by an expression of CaV1.3 and simultaneous ablation of CaV1.2 in GABAergic interneurons could balance early cortical disturbances manifested as contralateral hyperexcitability in the early phase after TBI. The switch of the VGCC alpha Subunits in GABAergic interneurons was detected using the GAD67-GFP (Glutamate Decarboxylase 67 – Green Fluorescent Protein) Knock-in mouse line. Mice received a TBI with a Controlled Cortical Impact (CCI) to the primary motor and somatosensory cortex at postnatal day 19-21 under anesthesia in vivo. Single GFP+ interneurons located in the undamaged, contralateral cortex were isolated by Fluorescence-Activated Cell Sorting (FACS) and further analyzed by Mass Spectrometry (MS). The switch was associated with an increased excitability of Somatostatin (SST) interneurons and extracellular network activity in acute brain slices in Microelectrode Array (MEA) recordings, which could be restored in presence of isradipine (100 nM), which selectively blocks CaV1.3-containing VGCCs. These data suggest that a switch in alpha.subunits of VGCCs expressed on SST-positive interneurons stabilizes early hyperactivity of the contralateral cortical network at 72 h after TBI, thereby promoting an adaptive mechanism to counterbalance post-traumatic hyperexcitabilty that might lead to epileptogenesis.
Project description:Background: V0v spinal interneurons are highly-conserved, glutamatergic, commissural neurons that function in locomotor circuits. We have previously shown that Evx1 and Evx2 are required to specify the neurotransmitter phenotype of these cells. However, we still know very little about the gene regulatory networks that act downstream of these transcription factors in V0v cells. Methods: To identify candidate members of V0v gene regulatory networks, we FAC-sorted WT and evx1;evx2 double mutant zebrafish V0v spinal interneurons and expression-profiled them using microarrays and scRNA-seq. We also used in situ hybridization to compare expression of a subset of candidate genes in evx1;evx2 mutants and wild-type siblings. Results: Our data reveal two molecularly-distinct subtypes of V0v spinal interneurons at 48 h and suggest that, by this stage of development, evx1;evx2 double mutant cells transfate into either inhibitory spinal interneurons, or motoneurons. Our results also identify 25 transcriptional regulator genes that require Evx1/2 for their expression in V0v interneurons, plus a further 11 transcriptional regulator genes that are repressed in V0v interneurons by Evx1/2. Two of the latter genes are hmx2 and hmx3a. Intriguingly, we show that Hmx2/3a, repress dI2 interneuronal expression of skor1a and nefma, two genes that require Evx1/2 for their expression in V0v interneurons. This suggests that Evx1/2 might regulate skor1a and nefma expression in V0v interneurons by repressing Hmx2/3a expression. Conclusions: This study identifies two molecularly-distinct subsets of V0v spinal interneurons, as well as multiple transcriptional regulators that are strong candidates for acting downstream of Evx1/2 to specify the essential functional characteristics of V0v interneurons. Our data further suggest that in the absence of both Evx1 and Evx2, V0v spinal interneurons initially change their neurotransmitter phenotypes from excitatory to inhibitory and then, later, start to express markers of distinct types of inhibitory spinal interneurons, or motoneurons. Taken together, our findings significantly increase our knowledge of V0v spinal development and move us closer towards the essential goal of identifying the complete gene regulatory networks that specify this crucial cell type.
Project description:During cortical development, radial glial cells, known as neural stem cells, initially generate a large number of cortical glutamatergic pyramidal neurons through a process called neurogenesis. This is followed by the generation of a diversity of cortical astrocytes, oligodendrocytes, and olfactory bulb interneurons, known as gliogenesis. However, the molecular mechanisms underlying the switch from cortical neurogenesis to gliogenesis, and the subsequent fate determination of cortical astrocytes, oligodendrocytes, and olfactory bulb interneurons, remain unclear. Here, we report that extracellular signal-regulated kinase (ERK) signaling plays a fundamental role in promoting cortical gliogenesis and the generation of cortical glial progenitors. Additionally, SHH-SMO-GLI activator signaling has an auxiliary function to ERK during these processes. We further demonstrate that NOTCH signaling is absolutely required for the fate determination of astrocytes, while ERK signaling plays a prominent role in oligodendrocyte fate specification, and SHH signaling is crucial for the fate determination of olfactory bulb interneurons from cortical progenitors. We provide evidence suggesting that this mechanism is conserved in both mice and humans. Finally, we propose a unifying principle of mammalian cortical gliogenesis.
Project description:Background: V0v spinal interneurons are highly-conserved, glutamatergic, commissural neurons that function in locomotor circuits. We have previously shown that Evx1 and Evx2 are required to specify the neurotransmitter phenotype of these cells. However, we still know very little about the gene regulatory networks that act downstream of these transcription factors in V0v cells. Methods: To identify candidate members of V0v gene regulatory networks, we FAC-sorted WT and evx1;evx2 double mutant zebrafish V0v spinal interneurons and expression-profiled them using microarrays and scRNA-seq. We also used in situ hybridization to compare expression of a subset of candidate genes in evx1;evx2 mutants and wild-type siblings. Results: Our data reveal two molecularly-distinct subtypes of V0v spinal interneurons at 48 h and suggest that, by this stage of development, evx1;evx2 double mutant cells transfate into either inhibitory spinal interneurons, or motoneurons. Our results also identify 25 transcriptional regulator genes that require Evx1/2 for their expression in V0v interneurons, plus a further 11 transcriptional regulator genes that are repressed in V0v interneurons by Evx1/2. Two of the latter genes are hmx2 and hmx3a. Intriguingly, we show that Hmx2/3a, repress dI2 interneuronal expression of skor1a and nefma, two genes that require Evx1/2 for their expression in V0v interneurons. This suggests that Evx1/2 might regulate skor1a and nefma expression in V0v interneurons by repressing Hmx2/3a expression. Conclusions: This study identifies two molecularly-distinct subsets of V0v spinal interneurons, as well as multiple transcriptional regulators that are strong candidates for acting downstream of Evx1/2 to specify the essential functional characteristics of V0v interneurons. Our data further suggest that in the absence of both Evx1 and Evx2, V0v spinal interneurons initially change their neurotransmitter phenotypes from excitatory to inhibitory and then, later, start to express markers of distinct types of inhibitory spinal interneurons, or motoneurons. Taken together, our findings significantly increase our knowledge of V0v spinal development and move us closer towards the essential goal of identifying the complete gene regulatory networks that specify this crucial cell type.
Project description:Our research is to investigate the role of Brpf1 in the development and function of GABAergic interneurons. To test this, we used mouse primary in vitro cultured GABAergic interneurons derived from medial ganglionic eminence (MGE) and utilized AAV-shBrpf1 virus to knockdown Brpf1. We performed mRNA-seq on the total RNA extracted from the infected neurons .We found that most of the up-regulated genes after Brpf1 knockdown were involved in processes such as protein binding, gene negative transcription, ubiquitination, and inflammation by mRNA-seq. We found that many genes related to neuronal calcium, potassium ion transport and neurotransmitter release changed after Brpf1 was knockdown.Our results demonstrate the key role of Brpf1 in related gene expression of GABAergic interneurons, and provide new lights on the underlying neurobiological mechanisms of BRPF1 mutations that cause mental retardation in children or adolescents.
Project description:During cortical development, radial glial cells, known as neural stem cells, initially generate a large number of cortical glutamatergic pyramidal neurons through a process called neurogenesis. This is followed by the generation of a diversity of cortical astrocytes, oligodendrocytes, and olfactory bulb interneurons, known as gliogenesis. However, the molecular mechanisms underlying the switch from cortical neurogenesis to gliogenesis, and the subsequent fate determination of cortical astrocytes, oligodendrocytes, and olfactory bulb interneurons, remain unclear. Here, we report that extracellular signal-regulated kinase (ERK) signaling plays a fundamental role in promoting cortical gliogenesis and the generation of cortical glial progenitors. Additionally, SHH-SMO-GLI activator signaling has an auxiliary function to ERK during these processes. We further demonstrate that NOTCH signaling is absolutely required for the fate determination of astrocytes, while ERK signaling plays a prominent role in oligodendrocyte fate specification, and SHH signaling is crucial for the fate determination of olfactory bulb interneurons from cortical progenitors. We provide evidence suggesting that this mechanism is conserved in both mice and humans. Finally, we propose a unifying principle of mammalian cortical gliogenesis.
Project description:Chronic stress is a major triggering factor for neuropsychiatric disorders including obsessive-compulsive disorder (OCD), a mental health condition characterized by motor stereotypies and striatal overactivation. However, the mechanisms at the cell- and microcircuit-level through which stress triggers motor symptoms is currently unknown. Here, we report that chronic stress (CS) in mice alters dorsomedial striatum (DMS) function, by affecting GABAergic interneuron populations and somatostatin-positive (SOM) interneurons in particular. Specifically, we show that CS impairs communication between SOM interneurons and medium spiny neurons, promoting striatal overactivation / disinhibition and increased motor output. Using probabilistic machine learning for analyzing animal behavior we further demonstrate that in vivo chemogenetic manipulation of SOM interneurons in DMS modulates motor phenotypes in stressed mice. Altogether, we propose a causal link between dysfunction of striatal SOM interneurons and motor symptoms in stress-related neuropsychiatric disorders.
Project description:The gene targeted NKX2.1GFP/w hESC line was differentiated as spin EBs in BPEL medium supplemented with FGF2 and retinoic acid to generate NKX2.1-GFP+ neural cells. NKX2.1-GFP+ cells were FACS sorted and further differentiated in serum free BEL medium supplemented with FGF2 (20 ng/ml) and EGF1 (20 ng/ml) on laminin-coated flasks. After ~ 90 days in culture, cells were FACS sorted based on FORSE-1 and NKX2.1-GFP expression, with the FORSE-1-GFP- fraction further fractionated on the basis of PDGFR? expression. Sorted fractions were subjected to Illumina microarray processing.
Project description:The goals of this study is to compare transcriptome profiles (RNA-seq) of zebrafish V2a interneurons with regrown axon and those without regrown axon in the spinal segments rostral to the lesion after spinal cord injury. For purification of V2a interneurons with regrown axon, the fluorescent tracer Rhodamine Dextran (RD) was retrogradely applied to Tg(Chx10:GFP) fish at three or eight weeks post injury. Spinal cord segments rostral to the lesion site was collected from 20 fish at 3- or 8 wpi, and corresponding spinal cord segments from 20 uninjured fish were collected as control material. GFP+/RD+ and GFP+/RD- cells were FAC-sorted and subjected to RNA-sequencing. Total RNA was isolated using SMART-SeqTM v4 UltraTM Low Input RNA Kit for Sequencing (Clontech). Sequencing libraries (N=5-6) were generated using NEBNext UltraTM RNA Library Prep Kit for Illumina following the manufacturer’s instructions (NEB). We mapped about 40-80 million sequence reads per sample to the zebrafish genome and identified 42,370 transcripts in the zebrafish V2a interneurons in the spinal cord. Our study represents the detailed analysis of transcriptomes of zebrafish V2a interneurons with regrown axon and those without regrown axon in the spinal segments rostral to the lesion after spinal cord injury.