Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

S-SCAM is essential for synapse formation

ABSTRACT: Synapse formation is critical for the wiring of neural circuits in the developing brain. The synaptic scaffolding protein S-SCAM/MAGI-2 has important roles in the assembly of signaling complexes at postsynaptic densities. However, the role of S-SCAM in establishing the entire synapse is not known. Here, we report significant effects of RNAi-induced S-SCAM knockdown on the number of synapses in early stages of network development in vitro. In vivo knockdown during the first three postnatal weeks reduced the number of dendritic spines in the rat brain neocortex. Knockdown of S-SCAM in cultured hippocampal neurons severely reduced the clustering of both pre- and postsynaptic components. This included synaptic vesicle proteins, pre- and postsynaptic scaffolding proteins, and cell adhesion molecules, suggesting that entire synapses fail to form. Correspondingly, functional and morphological characteristics of developing neurons were affected by reducing S-SCAM protein levels: neurons displayed severely impaired synaptic transmission and reduced dendritic arborization. A next generation sequencing approach showed normal expression of housekeeping genes, but changes of expression levels in 39 synaptic signaling molecules in cultured neurons. These results indicate that S-SCAM mediates the recruitment of all key classes of synaptic molecules during synapse assembly and is critical for the development of neural circuits in the developing brain.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE228093 | GEO | 2023/10/02

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

A Specific Neuroligin3-αNeurexin1Signaling Regulates GABAergic Synaptic Function in Mouse Hippocampus

Project description:Synapses are fundamental organizers of precise signal propagation between neurons. Maintaining synapse assemblies require interactions between pre- and post- synaptic proteins, notably cell adhesion molecules (CAMs). It has been proposed that the function of Neuroligins (Nlgn1 - 4), postsynaptic CAMs, relies on the formation of trans-synaptic complexes with Neurexins (Nrxs), presynaptic CAMs. Nlgn3 is a unique Nlgn isoform that localizes at both excitatory and inhibitory synapses. However, Nlgn3 function mediated through Nrx interaction is mostly unknown. Here, we find for the first time that Nlgn3 localizes at postsynaptic sites apposing vesicular glutamate transporter 3 (VGT3)-expressing inhibitory terminals. Overexpression and knockdown approaches indicate that Nlgn3 regulates VGT3-positive inhibitory interneuron-mediated synaptic transmission. Fluorescent in situ hybridization and single-cell RNA sequencing studies revealed that αNrxn1 and βNrxn3 are VGT3 interneuron-specific Nrxn isoforms and the expression levels of Nrxn splice isoforms are highly diverse in VGT3 interneurons, respectively. Most importantly, postsynaptic Nlgn3 requires presynaptic αNrx1+AS4 expressed in VGT3-positive interneurons to regulate inhibitory synaptic transmission. Our results strongly suggest that specific Nlgn-Nrx interaction generate distinct functional properties at synapses.

2021-01-04 | GSE150989 | GEO

Mapping the proteome of the synaptic cleft through peroxidase-based reporter protein SynCAM1-HRP

Project description:Synapses are the brain’s functional units connecting neurons into circuits that underlie memory and behavior. These specialized neuronal junctions are heterogenic in function and molecular composition, reflecting diverse health and disease states. Progress over the past years has shown that trans-synaptic adhesion molecules mediate synapse formation, specification, and differentiation during development. Among the prominently expressed synaptic cleft proteins are SynCAMs, a group of immunoglobulin molecules that engage in homo- and heterophilic interactions and that instruct synapse formation and guide synaptic maturation and that are specific for excitatory synapses. The current study describes the use of peroxidase-mediated proximity labeling to map the proteome of excitatory synapses using SynCAM1 as a reporter protein.

2018-12-04 | PXD011312 | Pride

NONO mutations cause syndromic intellectual disability and inhibitory synaptic defects

Project description:Identifying causes of sporadic intellectual disability remains a considerable medical challenge. Here, we demonstrate that null mutations in the NONO gene, a member of the Drosophila Behavior Human Splicing (DBHS) protein family, are a novel cause of X-linked syndromic intellectual disability. Comparing humans to Nono-deficient mice revealed related behavioral and craniofacial anomalies, as well as global transcriptional dysregulation. Nono-deficient mice also showed deregulation of a large number of synaptic transcripts, causing a disorganization of inhibitory synapses, with impaired postsynaptic scaffolding of gephyrin. Alteration of gephyrin clustering could be rescued by over-expression of Gabra2 in NONO-compromised neurons. These findings link NONO to intellectual disability and first highlight the key role of DBHS proteins in functional organization of GABAergic synapses.

2015-09-02 | E-MTAB-2895 | biostudies-arrayexpress

NONO mutations cause syndromic intellectual disability and inhibitory synaptic defects

2015-09-02 | E-MTAB-2894 | biostudies-arrayexpress

Neuroligin 3 Splice Isoforms Shape Mouse Hippocampal Inhibitory Synaptic Function

Project description:Synapse formation is a dynamic process essential for neuronal circuit development and maturation. At the synaptic cleft, trans-synaptic protein-protein interactions constitute major biological determinants of proper synapse efficacy. The balance of excitatory and inhibitory synaptic transmission (E-I balance) stabilizes synaptic activity and its dysregulation has been implicated in neurodevelopmental disorders including autism spectrum disorders. However, the molecular mechanisms underlying E-I balance remains to be elucidated. Here, we investigate Neuroligin (Nlgn) genes which encode a family of postsynaptic adhesion molecules that shape excitatory and inhibitory synaptic function. We identified that NLGN3 protein differentially regulates inhibitory synaptic transmission in a splice isoform-dependent manner in hippocampal CA1 synapses. Distinct subcellular localization patterns of NLGN3 isoforms contribute to the functional differences observed among splice variants. Finally, our single-cell sequencing analysis reveals that Nlgn1 and Nlgn3 are the major Nlgn genes and that Nlgn splice isoforms are highly diverse in CA1 pyramidal neurons.

2020-05-05 | GSE143295 | GEO

Neuroligin-4 Regulates Excitatory Synaptic Transmission in Human Neurons

Project description:The autism-associated synaptic-adhesion gene Neuroligin-4 (NLGN4) is poorly conserved evolutionarily, limiting conclusions from Nlgn4 mouse models for human cells. Here, we show that the cellular and subcellular expression of human and murine Neuroligin-4 differ, with human Neuroligin-4 primarily expressed in cerebral cortex and localized to excitatory synapses. Overexpression of NLGN4 in human neurons resulted in an increase in excitatory synapse numbers but a remarkable decrease in synaptic strength. Human neurons carrying the syndromic autism mutation NLGN4-R704C also formed more excitatory synapses but with increased functional synaptic transmission due to a postsynaptic mechanism, while genetic loss of NLGN4 did not significantly affect synapses in the human neurons analyzed. Thus, the NLGN4-R704C mutation represents a change of function mutation. Our work reveals contrasting roles of NLGN4 in human and mouse neurons, suggesting human evolution has impacted even fundamental cell biological processes generally assumed to be highly conserved.

2019-06-27 | GSE131428 | GEO

Single-cell transcriptome depicts the molecular dynamics of synapse formation in mouse hippocampus

Project description:Synapses are asymmetric junctions between presynaptic and postsynaptic neurons that mediate information transfer in the brain. The proper formation of functional synapses is crucial for synaptic transmission and brain function. However, how neurons initially recognize each other to form synapses remain to be elucidated. Here, we performed single-cell RNA sequencing of the cultured hippocampal cells on the critical time points during synapse development. . We first built comprehensive single-cell transcriptomic atlas of hippocampus undergoing synapse formation. Furthermore, we focused on neurons, and systematically analyzed temporal dynamic functional transcription factors hubs.. We identified that transcription factors, such as EGR family genes, AP-1 family genes, NeuroD family genes, NF1 family genes, may act as key regulators of synapse formation. Besides, we provided the resources of increased membrane and secretory proteins associated with synapse formation, which including previously reported synapse formation genes, Nlgn3, Nectin1, Dag1, Snap25, and the newly identified potential genes, Tmem65, Grm5, Olfm1, Timp3. Finally, we analyzed the changes of cell communication signaling pathways in neurons before and after synapse formation, and identified several important signaling pathways, including NRXN, NCAM, BMP, NEGR, and so on. Collectively, our work provided a holistic view of the molecular dynamics of the hippocampal synapse formation.

2023-12-30 | GSE212792 | GEO

Synaptic Signatures and Disease Vulnerabilities of Layer 5 Pyramidal Neurons - second data set

Project description:Cortical layer 5 (L5) intratelencephalic (IT) and pyramidal tract (PT) neurons are embedded in distinct information processing pathways. The morphology, connectivity, electrophysiological properties, and role in behavior of these neurons have been extensively analyzed. However, the molecular composition of their synapses remains largely uncharacterized. Here, we dissect the protein composition of the excitatory postsynaptic compartment of L5 neurons in intact somatosensory circuits, using an optimized proximity biotinylation workflow with subsynaptic resolution. We find distinct synaptic signatures of L5 IT and PT neurons that are defined by proteins regulating synaptic organization and transmission, including cell-surface proteins (CSPs), neurotransmitter receptors and ion channels. In addition, we find a differential vulnerability to disease, with a marked enrichment of autism risk genes in the synaptic signature of L5 IT neurons compared to PT neurons. Our results align with human studies and suggest that the excitatory postsynaptic compartment of L5 IT neurons is notably susceptible in autism. Together, our analysis sheds light on the proteins that regulate synaptic organization and function of L5 neuron types and contribute to their susceptibility in disease. Our approach is versatile and can be broadly applied to other neuron types to create a protein-based, synaptic atlas of cortical circuits.

2024-11-04 | PXD052081 | Pride

Data for Alternative Splicing of Adhesion-GPCR Latrophilin-3 Controls Synapse Formation

Project description:How synapses are assembled and specified in brain is incompletely understood. Latrophilin-3, a postsynaptic adhesion-GPCR, mediates Schaffer-collateral synapse formation in the hippocampus but the mechanisms involved remained unclear. Here we show that Latrophilin-3 organizes synapses by a convergent dual-pathway mechanism by which Latrophilin-3 simultaneously activates GaS/cAMP-signaling and recruits phase-separated postsynaptic protein scaffolds. We found that cell type-specific alternative splicing of Latrophilin-3 controls its G protein coupling mode, resulting in Latrophilin-3 variants that predominantly signal via Gas and cAMP or via Gα12/13. A CRISPR-mediated genetic switch of Latrophilin-3 alternative splicing from a GaS- to a Gα12/13-coupled mode impaired synaptic connectivity similar to the overall deletion of Latrophilin-3, suggesting that GaS/cAMP-signaling by Latrophilin-3 splice variants mediates synapse formation. Moreover, GaS- but not Gα12/13-coupled splice variants of Latrophilin-3 recruit phase-transitioned postsynaptic protein scaffolds that are clustered by binding of presynaptic Latrophilin-3 ligands. Strikingly, neuronal activity promotes alternative splicing of the synaptogenic variant of Latrophilin-3, thereby enhancing synaptic connectivity. Together, these data suggest that activity-dependent alternative splicing of a key synaptic adhesion molecule controls synapse formation by parallel activation of two convergent pathways, GaS/cAMP signaling and the phase separation of postsynaptic protein scaffolds.

2023-10-19 | GSE240791 | GEO

Activity-induced Nr4a1 regulates spine density and distribution pattern of excitatory synapses in pyramidal neurons

Project description:Excitatory synapses occur mainly on dendritic spines, and spine density is usually correlated with the strength of excitatory synaptic transmission. We report that Nr4a1, an activity-inducible gene encoding a nuclear receptor, regulates the density and distribution of dendritic spines in CA1 pyramidal neurons. Nr4a1 overexpression resulted in elimination of the majority of spines; however, postsynaptic densities were preserved on dendritic shafts, and the strength of excitatory synaptic transmission was unaffected, showing that excitatory synapses can be dissociated from spines. mRNA expression profiling studies suggest that Nr4a1-mediated transcriptional regulation of the actin cytoskeleton contributes to this effect. Under conditions of chronically elevated activity, when Nr4a1 was induced, Nr4a1 knockdown increased the density of spines and PSDs specifically at the distal ends of dendrites. Thus, Nr4a1 is a key component of an activity-induced transcriptional program that regulates the density and distribution of spines and synapses. After 10 days in culture, dissociated mouse hippocampal neurons in 6-well plates were infected with lentivirus expressing either Flag-Nr4a1 or GFP and incubated for 6 days to allow for transgene expression. Total RNA was then isolated using RNeasy Plus kit (QIAGEN). Samples passing an mRNA quality check proceeded to quantitative analysis on Agilent-026655 4x44 Mouse Microarrays.

2016-01-13 | E-GEOD-76805 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data