Project description:Amyotrophic lateral sclerosis (ALS) is an incurable disease characterized by proteinaceous aggregate accumulation and neuroinflammation culminating in rapidly progressive lower and upper motor neuron death. To interrogate cell-intrinsic and inter-cell type perturbations in ALS, single-nucleus RNA sequencing was performed on the lumbar spinal cord in the murine ALS model SOD1G93A transgenic and littermate control mice at peri-symptomatic onset stage of disease, age 90 days. This work uncovered perturbed tripartite synapse functions, complement activation and metabolic stress in the affected spinal cord; processes evidenced by cell death and proteolytic stress-associated gene sets. Concomitantly, these pro-damage events in the spinal cord co-existed with dysregulated reparative mechanisms. This work provides a resource of cell-specific niches in the ALS spinal cord and asserts that interwoven dysfunctional neuronal-glial communications mediating neurodegeneration are underway prior to overt disease manifestation and are recapitulated, in part, in the human post-mortem ALS spinal cord.
Project description:Amyotrophic lateral sclerosis (ALS) is an incurable disease characterized by proteinaceous aggregate accumulation and neuroinflammation culminating in rapidly progressive lower and upper motor neuron death. To interrogate cell-intrinsic and inter-cell type perturbations in ALS, single-nucleus RNA sequencing was performed on the lumbar spinal cord in the murine ALS model SOD1G93A transgenic and littermate control mice at peri-symptomatic onset stage of disease, age 90 days. This work uncovered perturbed tripartite synapse functions, complement activation and metabolic stress in the affected spinal cord; processes evidenced by cell death and proteolytic stress-associated gene sets. Concomitantly, these pro-damage events in the spinal cord co-existed with dysregulated reparative mechanisms. This work provides a resource of cell-specific niches in the ALS spinal cord and asserts that interwoven dysfunctional neuronal-glial communications mediating neurodegeneration are underway prior to overt disease manifestation and are recapitulated, in part, in the human post-mortem ALS spinal cord.
Project description:To better understand how the expression of a mutant gene that causes ALS can perturb the normal phenotype of astrocytes, and to identify genes that may have a role in their toxic effect on motor neurons, we used oligonucleotide arrays to compare the global gene expression profiles of glia overexpressing the mutant SOD1G93A protein with two different sets of controls: non-transgenic glia and glia overexpressing the wild type form of the human SOD1 protein (P<0.001) . Glia were derived from P1-P3 mouse pups transgenic for SOD1G93A (G93A), SOD1WT (WT) or non-transgenic pups (NT). Once the cells reached confluence, total RNA was isolated using Trizol (Invitrogen) from three different biological replicates for each type of glia. RNA was amplified by one round of T7 transcription using the Illumina TotalPrep RNA Amplification Kit. Illumina Bead Array Reader. Analysis was done using the Illumina Bead Studio Program.
Project description:This project is "Phosphoproteomic analysis of the lumbar spinal cord, a lesion site in the amyotrophic lateral sclerosis (ALS) mouse model SOD1G93A mice". The aim of this study is to clarify the phosphorylation changes by the lumbar spinal cord of SOD1G93A mice at 20w by applying proteomics technology. The goal of this study is to better understand the pathogenesis of ALS. lumbar spinal cord of SOD1G93A mice (n=5) and WT mice (n=4) were collected at 20w, and the phosphoproteomics were compared.
Project description:Expression profiling of lumbar spinal cord from MLC/SOD1G93A mice and age matched controls at 120 days of age. We used Affymetrix GeneChip Mouse Gene expression 2.0 st Array to determine differential gene expression. Samples were collected from mice MLC/SOD1G93A and controls FVB age matched at 4 month-old. Samples were collected representing each genotype and age group for RNA extraction and hybridization on Affymetrix Microarrays.
Project description:To better understand how the expression of a mutant gene that causes ALS can perturb the normal phenotype of astrocytes, and to identify genes that may have a role in their toxic effect on motor neurons, we used oligonucleotide arrays to compare the global gene expression profiles of glia overexpressing the mutant SOD1G93A protein with two different sets of controls: non-transgenic glia and glia overexpressing the wild type form of the human SOD1 protein (P<0.001) .
Project description:Amyotrophic Lateral Sclerosis (ALS) is an adult-onset and fast progression neurodegenerative disease that leads to the loss of motor neurons. Mechanisms of selective motor neuron loss in ALS are unknown. The early events occurring in the spinal cord that may contribute to motor neuron death are not described, neither astrocytes participation in the pre-symptomatic phases of the disease. In order to identify ALS early events, we performed a microarray analysis employing a whole mouse genome platform to evaluate the gene expression pattern of lumbar spinal cords of transgenic SOD1G93A mice and their littermate controls at pre-symptomatic ages of 40 and 80 days. Differentially expressed genes were identified by means of the Bioconductor packages Agi4x44Preprocess and limma. FunNet web based tool was used for analysis of over-represented pathways. Furthermore, immunolabeled astrocytes from 40 and 80 days old mice were submitted to laser microdissection and RNA was extracted for evaluation of a selected gene by qPCR. Statistical analysis has pointed to 492 differentially expressed genes (155 up and 337 down regulated) in 40 days and 1105 (433 up and 672 down) in 80 days old ALS mice. The KEGG pathways tight junction, antigen processing and presentation, oxidative phosphorylation, endocytosis, chemokine signaling pathway, ubiquitin mediated proteolysis and glutamatergic synapse were found over-represented at both 40 and 80 days pre-symptomatic ages. Ube2i gene expression was evaluated in astrocytes from both transgenic ages, being up regulated in 40 and 80 days astrocytes enriched samples. Our data points to important early molecular events occurring in pre-symptomatic phases of ALS in mouse model. Early SUMOylation process linked to astrocytes might account to non autonomous cell toxicity in ALS. Further studies on the signaling pathways presented here may provide new insights to better understand the events triggering motor neuron death in this devastating disorder. Whole lumbar spinal cord from SOD1G93A and Non transgenic controls from 40 and 80 days were used in the experiments. 4 biological replicates were used. A reference sample, comprised by RNA from different neonatal organs (heart, liver, kidney) were used in the hybridations
Project description:Expression profiling of lumbar spinal cord from MLC/SOD1G93A mice and age matched controls at 120 days of age. We used Affymetrix GeneChip Mouse Gene expression 2.0 st Array to determine differential gene expression.
Project description:Early molecular events related to cytoskeleton are poorly described in Amyotrophic Lateral Sclerosis (ALS), especially in the Schwann cell (SC), which offers strong trophic support to motor neurons. DAVID tool identified cytoskeleton-related genes by employing the Cellular Component of Gene Ontology (CCO) in a large gene profiling of lumbar spinal cord and sciatic nerve of presymptomatic SOD1G93A mice. One and five CCO terms related to cytoskeleton were described from the spinal cord deregulated genes of 40 days (actin cytoskeleton) and 80 days (microtubule cytoskeleton, cytoskeleton part, actin cytoskeleton, neurofilament cytoskeleton and cytoskeleton) old transgene mice, respectively. Also, four terms were depicted from the deregulated genes of sciatic nerve of 60 days old transgenes (actin cytoskeleton, cytoskeleton part, microtubule cytoskeleton and cytoskeleton). Kif1b was the unique gene that appeared deregulated in more than one studied region or presymptomatic age. The expression of Kif1b (qPCR) elevated in the lumbar spinal cord (40 days old) and decreased in the sciatic nerve (60 days old) of presymptomatic ALS mice, results that were in line to microarray findings. Upregulation (24.8 fold) of Kif1b was seen in laser microdissected enriched immunolabeled motor neurons from the spinal cord of 40 days old presymptomatic SOD1G93A mice. Furthermore, Kif1b was downregulated in the sciatic nerve Schwann cells of presymptomatic ALS mice (60 days old) that were enriched by means of cell microdissection (6.35 fold), cell sorting (3.53 fold) and primary culture (2.70 fold) technologies. The gene regulation of cytoskeleton molecules is an important occurrence in motor neurons and Schwann cells in presymptomatic stages of ALS and may be relevant in the dying back mechanisms of neuronal death. Differential regulation of Kif1b in the spinal cord and sciatic nerve cells emerged as key event in ALS. Sciatic nerve from SOD1G93A and Non transgenic controls from 60 days were used in the experiments. 4 biological replicates were used. A reference sample, comprised by RNA from different neonatal organs (heart, liver, kidney) were used in the hybridations