Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Subcellular transcriptome alterations in a cell culture model of spinal muscular atrophy point to widespread defects in axonal growth and presynaptic differentiation

ABSTRACT: Neuronal function critically depends on coordinated subcellular distribution of mRNAs. Disturbed mRNA processing and axonal transport has been found in spinal muscular atrophy and could be causative for dysfunction and degeneration of motoneurons. Despite the advances made in characterizing the transport mechanisms of several axonal mRNAs, an unbiased approach to identify the axonal repertoire of mRNAs in healthy and degenerating motoneurons has been lacking. Here we used compartmentalized microfluidic chambers to investigate the somatodendritic and axonal mRNA content of cultured motoneurons by microarray analysis. In axons, transcripts related to protein synthesis and energy production were enriched relative to the somatodendritic compartment. Knockdown of Smn, the protein deficient in spinal muscular atrophy, produced a large number of transcript alterations in both compartments. Transcripts related to immune functions, including MHC class I genes, and with roles in RNA splicing were upregulated in the somatodendritic compartment. On the axonal side, transcripts associated with axon growth and synaptic activity were downregulated. These alterations provide evidence that subcellular localization of transcripts with axonal functions as well as regulation of specific transcripts with nonautonomous functions is disturbed in Smn-deficient motoneurons, most likely contributing to the pathophysiology of spinal muscular atrophy.

ORGANISM(S): Mus musculus

PROVIDER: GSE59506 | GEO | 2014/12/01

SECONDARY ACCESSION(S): PRJNA255472

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Plastin 3 rescues deficient TrkB/BDNF signaling and protects from dysregulations in Ca2+ homeostasis in SMA mouse models

Project description:Spinal muscular atrophy (SMA) is a lethal pediatric neuromuscular disease caused by loss of the Survival Motor Neuron 1 gene (SMN1). Although current therapies focus very efficiently on SMN restoration, the cellular mechanisms underlying the pathological features are not fully understood. Smn-deficient motoneurons tremendously suffer from functional abnormalities leading to affected motoneuron differentiation and maturation. Based on our study, we could illustrate disturbed F-actin-dependent translocation of the Tropomyosin-kinase receptor B (TrkB) to the cell surface of axonal terminals of Smn-deficient motoneurons. This in turn results in impaired Brain-derived neurotrophic factor-induced TrkB activation and downstream signaling. Focusing on the F-actin bundling properties of the protective SMA modifier Plastin 3 revealed that its restoration significantly compensates altered TrkB surface recruitment and activation and ameliorates Cav2.1/2 cluster formation and cellular excitability in Smn-deficient motor axons. Thus, Plastin 3 supports in general two major cellular mechanisms indispensable for development and functional maintenance of motoneurons.

2023-01-05 | GSE197638 | GEO

hnRNP R and its main interactor, the noncoding RNA 7SK, coregulate the axonal transcriptome of motoneurons

Project description:Disturbed RNA processing and subcellular transport contribute to the pathomechanisms of motoneuron diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy. RNA-binding proteins are involved in these processes, but the mechanisms how they regulate the subcellular diversity of transcriptomes, in particular in axons, are not understood. hnRNP R interacts with several proteins involved in motoneuron diseases. It is located in axons of developing motoneurons and its depletion causes defects in axon growth. Here, we used iCLIP to determine the RNA interactome of hnRNP R in motoneurons. We identified ~3,500 RNA targets, predominantly with functions in synaptic transmission and axon guidance. Among the RNA targets identified by iCLIP, the non-coding RNA 7SK was the top interactor of hnRNP R. We detected 7SK in the nucleus but also in the cytosol of motoneurons. In axons, 7SK localized in close proximity to hnRNP R and depletion of hnRNP R reduced axonal 7SK. Furthermore, suppression of 7SK led to defective axon growth that was accompanied by axonal transcriptome alterations similar to those caused by hnRNP R depletion. Using a series of 7SK deletion mutants we show that the function of 7SK in axon elongation depends on its interaction with hnRNP R but not with the pTEF-B complex involved in transcriptional regulation. These results propose a role of 7SK as essential interactor of hnRNP R to regulate its function in axon maintenance.

2018-03-06 | GSE77101 | GEO

Ribosome profiling of SMN-primed ribosomes and active ribosome profiling from brains of a mouse model of severe SMA

Project description:Spinal muscular atrophy (SMA) is the most common genetic cause of infant mortality, with an incidence of around 1 in 6,000-10,000 live births. SMA is caused by low levels of full-length survival of motor neuron protein (SMN). We demonstrate that SMN binds to ribosomes and that this interaction is tissue-dependent. We performed ribosome profiling analyses on lysates from P5 wild-type mouse brains exposed to RNase I, from which we isolated SMN-primed ribosomes by immunoprecipitation. SMN-primed ribosomes are preferentially positioned within the first five codons of a set of mRNAs which are enriched for translational enhancer sequences in the 5’UTR and rare codons at the beginning of their coding sequence. These SMN-specific mRNAs are associated with neurogenesis, lipid metabolism, ubiquitination, chromatin regulation and translation. Additionally, we analyzed the positioning of active ribosomes using the Active-RiboSeq method based on RiboLace and compared early symptomatic SMA mouse brains to age-matched controls. We found that loss of SMN induces ribosome depletion, especially at the beginning of the coding sequence of SMN-specific mRNAs, leading to impairment of proteins involved in motor neuron function and stability. Keywords: motor neuron disease, spinal muscular atrophy, SMA, SMN, SMN1, survival of motor neuron, SMN-primed ribosome profiling, translation, RiboLace, Ribo-Seq, active translation, ribosome heterogeneity

2020-08-11 | GSE154106 | GEO

R-Roscovitine improves motoneuron function in mouse models for Spinal Muscular Atrophy.

Project description:Neurotransmission defects and motoneuron degeneration are hallmarks of Spinal Muscular Atrophy, a monogenetic disease caused by the deficiency of the SMN protein. In the present study, we show that systemic application of R-Roscovitine - a Cav2.1 / Cav2.2 channel modifier and a Cyclin-dependent kinase 5 (Cdk-5) inhibitor - significantly improved survival of SMA mice. In addition, R-Roscovitine increased Cav2.1 channel density and sizes of the motor endplates. In vitro, R-Roscovitine restored axon lengths and growth cone sizes of Smn-deficient motoneurons corresponding to enhanced spontaneous Ca2+ influx and elevated Cav2.2 channel cluster formations independent of its capability to inhibit Cdk-5. Acute application of R-Roscovitine at the neuromuscular junction significantly increased evoked neurotransmitter release, the frequency of spontaneous miniature potentials, and lowered the activation threshold of silent terminals. These data indicate that R-Roscovitine improves Ca2+ signaling and Ca2+ homeostasis in Smn-deficient motoneurons which is generally crucial for motoneuron differentiation, maturation, and function.

2020-01-28 | GSE112771 | GEO

Trancriptional regulation by axonal SMN on motor neuron cells

Project description:Muscular atrophy (SMA) is an autosomal recessive disease causing selective motor neuron death by the loss of telomeric survival motor neuron gene, SMN1. Axonal SMN, a-SMN, is a truncated form of SMN, derived from an alternatively spliced SMN1 gene. (Setola, et. al. 2007 PNAS 104, 1959-1964). The cellular clones expressing a-SMN in a tetracycline-dependent manner were isolated from NSC34 by two-step stable transfection, first with the tetracycline-repressor construct and subsequently with the a-SMN cDNA. To identify novel a-SMN target genes, the transcriptome of several a-SMN clones was analyzed and compared with that of parental cells.

2012-01-07 | E-MEXP-3402 | biostudies-arrayexpress

Loss of Tdp-43 disrupts the axonal transcriptome of motoneurons accompanied by impaired axonal translation and mitochondria function

Project description:Protein inclusions containing the RNA-binding protein TDP-43 are a pathological hallmark of amyotrophic lateral sclerosis and other neurodegenerative disorders. The loss of TDP-43 function that is associated with these inclusions affects post-transcriptional processing of RNAs in multiple ways including pre-mRNA splicing, nucleocytoplasmic transport, modulation of mRNA stability and translation. In contrast, less is known about the role of TDP-43 in axonal RNA metabolism in motoneurons. Here we show that depletion of Tdp-43 in primary motoneurons affects axon growth. This defect is accompanied by subcellular transcriptome alterations in the axonal and somatodendritic compartment. The axonal localization of transcripts encoding components of the cytoskeleton, the translational machinery and transcripts involved in mitochondrial energy metabolism were particularly affected by loss of Tdp-43. Accordingly, we observed reduced protein synthesis and disturbed mitochondrial functions in axons of Tdp-43-depleted motoneurons. Treatment with nicotinamide rescued the axon growth defect associated with loss of Tdp-43. These results show that Tdp-43 depletion in motoneurons affects several pathways integral to axon health indicating that loss of TDP-43 function could thus make a major contribution to axonal pathomechanisms in ALS.

2020-07-27 | GSE147607 | GEO

Suppression of NCALD protects against spinal muscular atrophy by restoring impaired endocytosis

Project description:Spinal muscular atrophy (SMA) is a common genetic motor neuron (MN) disease caused by low levels of the ubiquitously expressed housekeeping survival motor neuron (SMN) protein, whereas concomitant overexpression of plastin 3 (PLS3) protects from SMA. Here we identify neurocalcin delta (NCALD), a neuronal calcium sensor, as a second fully protective SMA modifier, which counteracts SMA pathology when downregulated. We show reduced Ca2+ influx and impaired endocytosis in SMA, which are crucial processes in synaptic vesicle recycling and neurotransmission. Remarkably, both reduced NCALD or increased PLS3 restore endocytosis in cell culture and MN function across species in zebrafish, worm and mouse SMA models, whereas Ca2+ influx remains disturbed. Furthermore, NCALD physically binds clathrin in a Ca2+-dependent manner. We propose that NCALD acts as a Ca2+-regulated inhibitor of endocytosis, and that endocytosis is critically affected in SMA. This finding opens new therapeutic avenues for SMA. Multifactorial design comparing affected patients and unaffected disease carriers against severly affected control group to identify disease modifying transcripts

2015-01-01 | E-GEOD-58316 | biostudies-arrayexpress

Pathologic alteration in the proteome of synaptosomes from the mouse model of spinal muscular atrophy

Project description:In this study, label-free quantitative proteomic analysis was performed using the Smn 2B/- mouse model to identify and investigate significant changes in protein abundance that may be related to the pathogenesis and neurodegeneration oberved in spinal muscular atrophy (SMA)

2019-07-04 | PXD012850 | Pride

Transcriptomic comparison of Drosophila snRNP biogenesis mutants reveals mutant-specific changes in pre-mRNA processing: implications for Spinal Muscular Atrophy

Project description:RNA-seq analysis of Drosophila snRNP biogenesis mutants. In brief, the Phax and Ars2 mutant RNA-seq was used in combination with Series GSE49587 (Smn mutant and wild-type Oregon-R RNA-seq) to classify transcriptome changes as snRNP-dependent or mutant specific. Additional flies with Smn transgenes, containing Smn mutations that cause Spinal Muscular Atrophy (SMA) in humans, were then used to determine whether the snRNP-dependent or mutant specific changes were present in intermediate models of SMA.

2016-05-05 | GSE81121 | GEO

Expression profiles of skeletal muscle from Taiwanese Smn-/-;SMN2 spinal muscular atrophy mouse model treated with Pip6a-PMO

Project description:Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by loss of survival motor neuron (SMN) protein. While SMN restoration therapies are beneficial, they are not a cure. We aimed to identify novel treatments to alleviate muscle pathology combining transcriptomics, proteomics and perturbational datasets. This revealed potential drug candidates for repurposing in SMA. One of the candidates, harmine, was further investigated in cell and animal models, improving multiple disease phenotypes, including SMN expression and lifespan. Our work highlights the potential of multiple and parallel data driven approaches for the development of novel treatments for use in combination with SMN restoration therapies.

2020-05-14 | GSE150517 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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