Project description:Single cell RNAseq was performed on naïve adult mouse lumbar dorsal root ganglia (DRG) cells. Neuronal and non-neuronal cell populations were identified.
Project description:Axonal regeneration is enhanced by prior conditioning peripheral nerve lesions. Here we show that Xenopus dorsal root ganglia (DRGs) with attached peripheral nerves (PN-DRGs) can be conditioned in vitro, thereafter showing enhanced axonal growth in response to neurotrophins, similar to preparations conditioned by axotomy in vivo. In contrast to freshly dissected preparations, conditioned PN-DRGs show abundant neurotrophin-induced axonal growth in the presence of actinomycin D, suggesting synthesis of mRNA encoding proteins necessary for axonal elongation occurs during the conditioning period, and this was confirmed by oligonucleotide micro-array analysis.
Project description:We have undertaken a genome-wide study of transcriptional activity in embryonic superior cervical ganglia (SCG) and dorsal root ganglia (DRG) during a time course of neurite outgrowth in vitro. Gene expression observed in these models likely includes both developmental gene expression patterns and regenerative responses to axotomy, which occurs as the result of tissue dissection. Comparison across both models revealed many genes with similar gene expression patterns during neurite outgrowth. These patterns were minimally affected by exposure to the potent inhibitory cue Semaphorin3A, indicating that this extrinsic cue does not exert major effects at the level of nuclear transcription. We also compared our data to several published studies of DRG and SCG gene expression in animal models of regeneration, and found the expression of a large number of genes in common between neurite outgrowth in vitro and regeneration in vivo. Experiment Overall Design: We wished to determine the transcriptional profiles of neurons undergoing neurite outgrowth in vitro. We were particularly interested in finding genes whose expression is generally associated with the process of neurite outgrowth, rather than with cell type-specific effects. Thus, in order to avoid focusing on transcripts unique to one tissue type versus another, we used a comparative strategy to look for effects that were common to two tissue types and therefore more likely to be involved in the general process of neurite outgrowth. While these explants contain multiple cell types, we felt this was preferable to the more disruptive conditions required to dissociate neurons or obtain a pure neuron population. To this end, we monitored gene expression in cultured explants from SCG and DRG using DNA microarrays. We initiated our studies by culturing embryonic day 13 (E13) mouse SCG in vitro and harvesting tissue for RNA isolation at time points from 2 to 65 hours. Time points were selected to detect both fast, short-term responses (2, 5 and 12 hours), as well as sustained, long-term changes (24, 40, and 65 hours). Samples were hybridized to Affymetrix MG-U74v2 A and B microarrays, with RNA from acutely dissected explants serving as a baseline reference. We followed these experiments with a parallel analysis of a more heterogeneous tissue type, the DRG, which is more frequently used than SCG for in vivo studies of neurite regeneration. Cervical and upper thoracic DRG from E12 embryos were cultured with NGF (the same trophic support as in SCG cultures), harvested at time points from 2 to 40 hours, and hybridized to Affymetrix MOE 430A microarrays.
Project description:We have undertaken a genome-wide study of transcriptional activity in embryonic superior cervical ganglia (SCG) and dorsal root ganglia (DRG) during a time course of neurite outgrowth in vitro. Gene expression observed in these models likely includes both developmental gene expression patterns and regenerative responses to axotomy, which occurs as the result of tissue dissection. Comparison across both models revealed many genes with similar gene expression patterns during neurite outgrowth. These patterns were minimally affected by exposure to the potent inhibitory cue Semaphorin3A, indicating that this extrinsic cue does not exert major effects at the level of nuclear transcription. We also compared our data to several published studies of DRG and SCG gene expression in animal models of regeneration, and found the expression of a large number of genes in common between neurite outgrowth in vitro and regeneration in vivo. Experiment Overall Design: We wished to determine the transcriptional profiles of neurons undergoing neurite outgrowth in vitro. We were particularly interested in finding genes whose expression is generally associated with the process of neurite outgrowth, rather than with cell type-specific effects. Thus, in order to avoid focusing on transcripts unique to one tissue type versus another, we used a comparative strategy to look for effects that were common to two tissue types and therefore more likely to be involved in the general process of neurite outgrowth. While these explants contain multiple cell types, we felt this was preferable to the more disruptive conditions required to dissociate neurons or obtain a pure neuron population. To this end, we monitored gene expression in cultured explants from SCG and DRG using DNA microarrays. We initiated our studies by culturing embryonic day 13 (E13) mouse SCG in vitro and harvesting tissue for RNA isolation at time points from 2 to 65 hours. Time points were selected to detect both fast, short-term responses (2, 5 and 12 hours), as well as sustained, long-term changes (24, 40, and 65 hours). Samples were hybridized to Affymetrix MG-U74v2 A and B microarrays, with RNA from acutely dissected explants serving as a baseline reference. We followed these experiments with a parallel analysis of a more heterogeneous tissue type, the DRG, which is more frequently used than SCG for in vivo studies of neurite regeneration. Cervical and upper thoracic DRG from E12 embryos were cultured with NGF (the same trophic support as in SCG cultures), harvested at time points from 2 to 40 hours, and hybridized to Affymetrix MOE 430A microarrays.
Project description:Here we studied the NOX2 dependent redox-proteome in dorsal root ganglia in mice. The overall goal was to assess the degree of NOX2-dependent changes in oxidised proteins following exposure to enriched enviroment and sciatic nerve axotomy in dorsal root ganglia.
Project description:The goal of this study was to analyze global gene expression in specific populations of somatosensory neurons in the periphery, including major, non-overlapping populations that include nociceptors, pruriceptors, and prorioceptors. The mammalian somatosensory nervous system encodes the perception of specific environmental stimuli. The dorsal root ganglion (DRG) contains distinct somatosensory neuron subtypes that innervate diverse peripheral tissues, mediating the detection of thermal, mechanical, proprioceptive, pruriceptive, and nociceptive stimuli. We purified discrete subtypes of mouse DRG somatosensory neurons by flow cytometry using fluorescently labeled mouse lines (SNS-Cre/TdTomato, Parv-Cre/TdTomato) in combination with Isolectin B4-FITC surface staining (IB4). This allowed identification of transcriptional differences between these major populations, revealing enrichment of voltage-gated ion channels, TRP channels, G-protein coupled receptors, transcription factors, and other functionally important classes of genes within specific somatosensory neuron subsets. SNS-Cre mice were bred with Rosa26-TdTomato mice to generate SNS-Cre/TdTomato reporter mice. Parv-Cre mice were bred with Rosa26-TdTomato mice to generate Parv-Cre/TdTomato mice. Isolectin B4-FITC was used to stain the surface of SNS-Cre/TdTomato reporter mice. We used these strategies of fluorescent labeling to purify distinct murine sensory neuron subsets from the dorsal root ganglia (DRG) by fluorescence activated cell sorting (FACS). Neurons were sorted directly in Qiazol for total RNA extraction and microarray analysis. Whole DRG tissue was also included for transcriptome analysis to compare with purified neuronal populations.
Project description:Gene expression profiling was carried out to compare labeled cRNA derived from 3 experimental groups. Group 1 was mRNA extracted from wild type dorsal root ganglia (DRG) taken from mice 10-12 weeks of age, Group 2 was mRNA extracted from DRG taken from NT-4 -/- mice of 4-5 weeks of age. Group 3 was mRNA extracted from DRGs taken from NT-4 -/- mice of 12 weeks of age. In all cases mRNA was extracted from 6-10 mice per group. The experiment was carried out a total of three times.
Project description:The goal of this study was to analyze global gene expression in specific populations of nociceptor sensory neurons, the neurons that detect damaging/noxious stimuli. The dorsal root ganglia (DRG), trigeminal ganglia, and nodose ganglia are anatomically distinct peripheral sensory ganglia that contain nociceptors which innervate skin, gut, lungs, and other distinct organ tissues. We used flow cytometry to purify nociceptors from these ganglia and profiled their global gene expression signatures to compare gene expression between these different anatomically distinct nociceptors. Nav1.8-Cre were bred with Rosa26-TdTomato to generate Nav1.8-Cre/R26-TdTomato reporter progeny, where all peripheral nociceptor neurons are genetically marked with red fluroescence due to specific expression of the TTX- resistant sodium channel Nav1.8. Lumbar region dorsal root ganglia (DRG), trigeminal ganglia, and nodose ganglia were dissected from mice (3 mice were pooled/sample). Highly red fluorescent neurons were Facs purified, RNA extracted, and processed for microarray analysis.