ABSTRACT: RNA-seq of rat dorsal root ganglia after ligation to investigate central nervous system transcriptomics in chronic pain using agnostic splice site discovery methods
Project description:Nociceptors play an essential role in both acute pain and chronic pain conditions. In this study, we examined the proteome of mouse dorsal root ganglia and compared NaV1.8Cre+/-; ROSA26-flox-stop-flox-DTA (Diphtheria toxin fragment A) mutant mice (NaV1.8Cre-DTA), in which NaV1.8-positive neurons (mainly nociceptors) in dorsal root ganglia (DRG) were ablated, with respective littermate wildtype controls.
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:Vagal afferent neurons are thought to convey primarily physiological information, whereas spinal afferents transmit noxious signals from the viscera to the central nervous system. In order to elucidate molecular identities for these different properties, we compared gene expression profiles of neurons located in nodose ganglia (NG) and dorsal root ganglia (DRG) in mice. Intraperitoneal administration of Alexa Fluor-488 conjugated Cholera toxin B allowed identification of neurons projecting to the viscera. Fluorescent neurons in DRG (from T10 to T13) and NG were isolated using laser capture microdissection. Gene expression profiles of visceral afferent neurons, obtained by microarray hybridization, were analysed using multivariate spectral map analysis, SAM algorithm (Significance Analysis of Microarray data) and fold-difference filtering. A total of 1996 genes were found to be differentially expressed in DRG versus NG, including 41 G-protein coupled receptors and 60 ion channels. Expression profiles obtained on laser-captured neurons were contrasted to those obtained on whole ganglia demonstrating striking differences and the need for microdissection when studying visceral sensory neurons because of dilution of the signal by somatic sensory neurons. Furthermore, a detailed catalogue of all adrenergic and cholinergic, GABA, glutamate, serotonin and dopamine receptors, voltage-gated potassium, sodium and calcium channels and transient receptor potential cation channels present in visceral afferents is provided. Our genome-wide expression profiling data provide novel insight into molecular signatures that underlie both functional differences and similarities between NG and DRG visceral sensory neurons. Moreover, these findings will offer novel insight into mode of action of pharmacologic agents modulating visceral sensation. Experiment Overall Design: Three separate experiments were performed. First, 5 whole dorsal root ganglia were compared to 7 whole nodose ganglia. Second, Laser captured visceral neurons derived from 5 dorsal root ganglia and 5 nodose ganglia were compared on MG-U74Av2. Third, Laser captured visceral neurons derived from 9 dorsal root ganglia and 11 nodose ganglia were compared on Mouse430_2.
Project description:Axon regeneration in the central nervous system (CNS) requires reactivating injured neurons’ intrinsic growth state and enabling growth in an inhibitory environment. Using an inbred mouse neuronal phenotypic screen, we find that CAST/Ei mouse adult dorsal root ganglion neurons extend axons more on CNS myelin than the other eight strains tested, especially when pre-injured. Injury-primed CAST/Ei neurons also regenerate markedly in the spinal cord and optic nerve more than those from C57BL/6 mice and show greater spouting following ischemic stroke. Heritability estimates indicate that extended growth in CAST/Ei neurons on myelin is genetically determined, and two whole-genome expression screens yield the Activin transcript Inhba as most correlated with this ability. These screens are presented here. Biological quadruplicate - Mouse tissue - Naïve Dorsal Root Ganglia (DRG) and 5 day post sciatic nerve crush DRG - x9 strains.
Project description:A comparative RNA-SEQ analysis of control total RNA preparations from pooled E14.5 dorsal root ganglia was carried out to determine the performance of the RNAseq reactions at differing concentrations (3ng, 10ng & 30ng in high or low volumes) and concordance among different institutions using the same source of RNA. RNA was extracted from E14.5 dorsal root ganglia dissected from wild type C57BL/6J embryos and sequenced using Illumina Hiseq 2500 platform.
Project description:Histone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. The aim of this study was to determine whether these compounds could also affect neuropathic pain. Different class I HDACIs were delivered intrathecally into rat spinal cord in models of traumatic nerve injury and antiretroviral drug-induced peripheral neuropathy (stavudine, d4T). Mechanical and thermal hypersensitivity was attenuated by 40% to 50% as a result of HDACI treatment, but only if started before any insult. The drugs globally increased histone acetylation in the spinal cord, but appeared to have no measurable effects in relevant dorsal root ganglia in this treatment paradigm, suggesting that any potential mechanism should be sought in the central nervous system. Microarray analysis of dorsal cord RNA revealed the signature of the specific compound used (MS-275) and suggested that its main effect was mediated through HDAC1. Taken together, these data support a role for histone acetylation in the emergence of neuropathic pain. n = 4, HDACi treated vs. vehicle treated. Ipsilateral dorsal spinal cord tissue after L5 spinal nerve transection, DRG tissue was run in a separate Affymetrix experiment.
Project description:We report the effects of vitamin E deficiency using the Ttpa-null mouse model on transcriptome profiles of dorsal root ganglia neurons