Project description:Familial amyotrophic lateral sclerosis (ALS) represents about 10% of ALS cases. In about 20% of familial ALS patients, a mutation in superoxide dismutase-1 (SOD1) can be found. The ubiquitous SOD1 protein converts superoxide radical anions to oxygen and hydrogen peroxide. Patients with familial ALS caused by mutations in SOD1 can show comorbidity with frontotemporal dementia and develop cognitive impairment, including apathy, inattention, verbal deficits, and hypersexuality. At the cellular level, pathological signs of ALS may include tau immunoreactive astrocytic and neuronal inclusions, suggesting that cognitive dysfunction in ALS may also reflect abnormal protein metabolism of the microtubule associated protein (MAP), tau. To identify cell-specific expression changes, we performed laser capture microdissection (LCM) to isolate anterior horn motor neurons and surrounding cells. To determine common pathways for the development of ALS due to dysfunction of SOD1 or TAU, we performed whole transcriptome analysis in SOD1 and TAU mouse models. Because ALS is a neurodegenerative disease that specifically affects motor neurons, these cells were the main investigative target. Global transcriptomes of glial cells surrounding the motor neurons were also assessed, because these cells have been implicated as triggers of neurodegeneration. Mouse experiments were performed at the presymptomatic stage, prior to the onset of cell loss, in order to reduce false positive signals due to tissue reactive changes. Lumbar anterior horn anterior horn motor neurons and surrounding cells (glia) were isolated from presymptomatic TAU-P301L and SOD1-G93A transgenic mice using laser capture microdissection (LCM; PixCellÂ® IIe LCM System, Arcturus, Molecular Devices, CA). On average, 500 motor neuron bodies or surrounding glial cells from 20 tissue sections per animal were collected. RNA isolation from LCM collected cells was performed using the Qiagen RNeasy Micro Kit. Only RNA with RNA Integrity Numbers (RIN) above 7.5 were taken for further analysis (Agilent Bioanalyzer 2100). A two-round T7-based amplification and labeling protocol (Agilent Low RNA Input Linear Amplification Kit PLUS) was used to generate high quality labeled cRNA. Agilent Whole Mouse Genome Microarray comparisons of motor neurons and surrounding glia were performed between transgenic (SOD1G93A and TAUP301L) and corresponding nontransgenic (control) littermate animals, producing four independent comparison groups: SOD1G93A motor neurons versus control motor neurons (SOD1mn), SOD1G93A motor neuron surrounding glia versus control glia (SOD1gl), TAUP301L motor neurons versus control motor neurons (TAUmn) and TAUP301L glia versus control glia (TAUgl). Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Raw microarray data were acquired using the Agilent DNA Microarray scanner and processed with the accompanying Agilent Feature Extraction 10.5 Image Analysis software using default settings. Normalized signal intensities were used to identify gene expression changes in SOD1G93A and TAUP301L motor neurons and surrounding glial cells, generating four partially overlapping sets of data. For the identification of differential expression, the genes were required to pass two conservative criteria: a ratio beyond the 99.5% confidence interval observed in homotypic comparisons, which corresponded to an approximately 1.5-fold expression change, and a paired t-test (P<0.01) computed using 100 permutations of the data for each gene. Correction for multiple comparisons was performed using the adjusted Bonferroni test. The analysis was performed in the TM4: Microarray Software Suite. These techniques identified 251 transcripts representing 186 known genes for which expression was altered in at least one of the four comparisons. Four-condition experiment, SOD1G93A motor neurons versus control motor neurons (SODmn), SOD1G93A motor neuron surrounding glia versus control glia (SODgl), TAUP301L motor neurons versus control motor neurons (TAUmn) and TAUP301L glia versus control glia (TAUgl). Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Biological replicates: 4 SOD1G93A motor neurons (SODmn), 4 non SOD littermate motor neurons (nonSODmn), 4 SOD1G93A motor neuron surrounding glia (SODgl), 4 non SOD littermate motor neuron surrounding glia (nonSODgl), 4 TAUP301L motor neurons (TAUmn), 4 non TAU littermate motor neurons (nonTAUmn), 4 TAUP301L motor neuron surrounding glia (TAUgl), 4 non TAU littermate motor neuron surrounding glia (nonTAUgl). Four independent comparison groups were generated: SOD1G93A motor neurons versus control nonSOD motor neurons, SOD1G93A motor neuron surrounding glia versus control nonSOD glia, TAUP301L motor neurons versus control nonTAU motor neurons and TAUP301L glia versus control nonTAU glia. Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Each replicate was repeated twice with dye flip to correct for unequal dye incorporation rates. Therefore, eight microarray hybridizations were performed for each biological comparison, for a total of 32 microarray slides and generating four groups of differentially expressed genes in SOD1G93A motor neurons (SODmn), SOD1G93A motor neuron surrounding glial cells (SODgl), TAUP301L motor neurons (TAUmn), and TAUP301L surrounding glial cells (TAUgl).

Project description:In our original grant we proposed to use the NR3B-null mouse model to study the role of NR3B subunit in motor neuron function. We have now successfully generated NR3B null mice. Interestingly, NR3B-null mice invariably die at age P4-P8. Our preliminary examination indicates that the motor strength of these mice is severely impaired prior to death. As we continue to explore the cause of death in NR3B null mice, we propose to conduct gene profiling experiments to search for transcription changes in the brain related to ablation of the NR3B gene. We have used the facility provided by the NINDS/NIMH Microarray Consortium to identify genes that show abnormal expression patterns in these mice. We would like to compare these changes with that opccured in SOD1 mice, a mouse model of motor neuron diseases. Analysis of these genes will help to identify changes in networks and pathways that may cause the death of NR3B-null mice. These studies will further help to elucidate the functional role of NR3B in motor neurons. We will compare samples from motor neurons of wild type and SOD1 mice to identify genes that show abnormal expression patterns, which may be implicated in the death of SOD1 mice and shared with the same changes in NR3B-null mice. We hypothesize that genes with their transcription level changing significantly in SOD1 mutant mice will be associated with the molecular mechanism underlying the death of motor neurons. We like to compare motor neuron and spinal cord smaples from SOD1 mice at the age prior to the disease onset. Total RNA from total 9 samples will be purified, each from ~200 motor neurons obtained by Laser Capture Microdissection and the total spinal cord. Extracted RNAs will be subjected to one or two rounds of amplification and the obtained cRNA will be biotinylated. The purified cRNA will be sent to the NINDS/NIMH Microarray Consortium be used to hybridize the GeneChip Mouse Genome 430 2.0 Array. The hybridization, scanning, and initial data analysis of these GeneChips will be conducted by the Consortium staff. We will analyze the collected data further after data collection. We will first identify genes that show significant changes between wild-type and SOD1 mice and then compare that with the result from NR3B null mice.

Project description:In our original grant we proposed to use the NR3B-null mouse model to study the role of NR3B subunit in motor neuron function. We have now successfully generated NR3B null mice. Interestingly, NR3B-null mice invariably die at age P4-P8. Our preliminary examination indicates that the motor strength of these mice is severely impaired prior to death. As we continue to explore the cause of death in NR3B null mice, we propose to conduct gene profiling experiments to search for transcription changes in the brain related to ablation of the NR3B gene. We have used the facility provided by the NINDS/NIMH Microarray Consortium to identify genes that show abnormal expression patterns in these mice. We would like to compare these changes with that opccured in SOD1 mice, a mouse model of motor neuron diseases. Analysis of these genes will help to identify changes in networks and pathways that may cause the death of NR3B-null mice. These studies will further help to elucidate the functional role of NR3B in motor neurons. We will compare samples from motor neurons of wild type and SOD1 mice to identify genes that show abnormal expression patterns, which may be implicated in the death of SOD1 mice and shared with the same changes in NR3B-null mice. We hypothesize that genes with their transcription level changing significantly by ablation of NR3B will be associated with the molecular mechanism underlying the death of motor neurons in NR3B null mice. As NR3B is expressed primarily in the motor neurons of hindbrain and spinal cord, we have first collected and analyzed the spinal cord samples from NR3B null mice and wild-type controls in P4, an age of disease onset. We like to compare motor neuron smaples from SOD1 mice at the age around the disease onset. Total RNA from total 6 samples will be purified from ~200 motor neurons obtained by Laser Capture Microdissection. Extracted RNAs will be subjected to two rounds of amplification and the obtained cRNA will be biotinylated. The purified cRNA will be sent to the NINDS/NIMH Microarray Consortium be used to hybridize the GeneChip Mouse Genome 430 2.0 Array. The hybridization, scanning, and initial data analysis of these GeneChips will be conducted by the Consortium staff. We will analyze the collected data further after data collection. We will first identify genes that show significant changes between wild-type and SOD1 mice and then compare that with the result from NR3B null mice.

Project description:In our original grant we proposed to use the NR3B-null mouse model to study the role of NR3B subunit in motor neuron function. We have now successfully generated NR3B null mice. Interestingly, NR3B-null mice invariably die at age P4-P8. Our preliminary examination indicates that the motor strength of these mice is severely impaired prior to death. As we continue to explore the cause of death in NR3B null mice, we propose to conduct gene profiling experiments to search for transcription changes in the brain related to ablation of the NR3B gene. We have used the facility provided by the NINDS/NIMH Microarray Consortium to identify genes that show abnormal expression patterns in these mice. We would like to compare these changes with that opccured in SOD1 mice, a mouse model of motor neuron diseases. Analysis of these genes will help to identify changes in networks and pathways that may cause the death of NR3B-null mice. These studies will further help to elucidate the functional role of NR3B in motor neurons. We will compare samples from motor neurons of wild type and SOD1 mice to identify genes that show abnormal expression patterns, which may be implicated in the death of SOD1 mice and shared with the same changes in NR3B-null mice. We hypothesize that genes with their transcription level changing significantly by ablation of NR3B will be associated with the molecular mechanism underlying the death of motor neurons in NR3B null mice. As NR3B is expressed primarily in the motor neurons of hindbrain and spinal cord, we have first collected and analyzed the spinal cord samples from NR3B null mice and wild-type controls in P4, an age of disease onset. We like to compare motor neuron and spinal cord smaples from SOD1 mice at the age prior to the disease onset. Total RNA from total 12 samples will be purified from ~200 motor neurons obtained by Laser Capture Microdissection and the total spinal cord. Extracted RNAs will be subjected to one or two rounds of amplification and the obtained cRNA will be biotinylated. The purified cRNA will be sent to the NINDS/NIMH Microarray Consortium be used to hybridize the GeneChip Mouse Genome 430 2.0 Array. The hybridization, scanning, and initial data analysis of these GeneChips will be conducted by the Consortium staff. We will analyze the collected data further after data collection. We will first identify genes that show significant changes between wild-type and SOD1 mice and then compare that with the result from NR3B null mice.

Project description:In our original grant we proposed to use the NR3B-null mouse model to study the role of NR3B subunit in motor neuron function. We have now successfully generated NR3B null mice. Interestingly, NR3B-null mice invariably die at age P4-P8. Our preliminary examination indicates that the motor strength of these mice is severely impaired prior to death. As we continue to explore the cause of death in NR3B null mice, we propose to conduct gene profiling experiments to search for transcription changes in the brain related to ablation of the NR3B gene. We have used the facility provided by the NINDS/NIMH Microarray Consortium to identify genes that show abnormal expression patterns in these mice. We would like to compare these changes with that opccured in SOD1 mice, a mouse model of motor neuron diseases. Analysis of these genes will help to identify changes in networks and pathways that may cause the death of NR3B-null mice. These studies will further help to elucidate the functional role of NR3B in motor neurons. We will compare samples from motor neurons of wild type and SOD1 mice to identify genes that show abnormal expression patterns, which may be implicated in the death of SOD1 mice and shared with the same changes in NR3B-null mice. We hypothesize that genes with their transcription level changing significantly in SOD1 mutant mice will be associated with the molecular mechanism underlying the death of motor neurons. We like to compare motor neuron and spinal cord smaples from SOD1 mice at the age prior to the disease onset. Total RNA from total 9 samples will be purified, each from ~200 motor neurons obtained by Laser Capture Microdissection and the total spinal cord. Extracted RNAs will be subjected to one or two rounds of amplification and the obtained cRNA will be biotinylated. The purified cRNA will be sent to the NINDS/NIMH Microarray Consortium be used to hybridize the GeneChip Mouse Genome 430 2.0 Array. The hybridization, scanning, and initial data analysis of these GeneChips will be conducted by the Consortium staff. We will analyze the collected data further after data collection. We will first identify genes that show significant changes between wild-type and SOD1 mice and then compare that with the result from NR3B null mice. Keywords: other

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