Project description:The complex nature of the transcriptional networks underlying addictive behaviors suggests intricate cooperation between diverse gene regulation mechanisms that go beyond canonical activity-dependent pathways. Here we implicate in this process a novel nuclear receptor transcription factor, Retinoid X Receptor Alpha (RXRα), which we identified bioinformatically as associated with addiction-like behaviors. In the nucleus accumbens (NAc) of male and female mice, we show that, while its own expression remains unaltered after cocaine exposure, RXRα controls plasticity- and addiction-relevant transcriptional programs in both dopamine receptor D1- and D2-expressing medium spiny neurons, which in turn modulate intrinsic excitability and synaptic activity of these NAc cell types. Behaviorally, bidirectional viral and pharmacological manipulation of RXRα regulates drug reward sensitivity in both non-operant and operant paradigms. Together, this study demonstrates a key role for NAc RXRα in promoting drug addiction, and paves the way for future studies of rexinoid signaling in psychiatric disease states.
Project description:We have aimed to analyze dexamethasone-induced transcriptional profiling in astrocytes and neurons of the mouse nucleus accumbens (NAc).
Project description:Animal models provide opportunity to study neurobiological aspects of human alcoholism. Changes in gene expression have been implicated in mediating brain function, including reward system and addiction. The current study aimed to identify novel genes that may underlie ethanol preference. Microarray analysis comparing gene expression in nucleus accumbens (NAc), hippocampus (HP) and prefrontal medial cortex (mPFC) was performed in two rat strains selected for extreme levels of ethanol preference - Warsaw High Preferring (WHP) and Warsaw Low Preferring (WLP). The identified candidate genes may underlie differential ethanol preference in rat model of alcoholism. This is analysis of 18 RNA samples, including 9 technical replicates. Two strains of rats selected for extreme levels of ethanol preference (low preferring WLP and high preferring WHP) were compared. Three brain areas (nucleus accumbens, prefrontal medial cortex and hippocampus) were studied. For each brain area, 6 RNA samples (including 3 technical replicates) were analyzed. Each RNA sample consist of of equal amounts of total RNA from 3 male rats. Comparisons: Nucleus accumbens of WHP vs. Nucleus accumbens of WLP; Prefrontal medial cortex of WHP vs. Prefrontal medial cortex of WLP; Hippocampus of WHP vs. Hippocampus of WLP. 3 biological replicates in each comparison.
Project description:Prenatal exposure to infectious or inflammatory insults can increase the risk of neuropsychiatric disorders with neurodevelopmental components, including schizophrenia and autism. The molecular processes underlying this pathological association are only partially understood. Here, we implemented an unbiased genome-wide transcriptional profiling of the nucleus accumbens of mice exposed to prenatal infection on GD17 compared to control subjects in order to elucidate the long term molecular signature of late prenatal infection. We used microarray analysis to investigate the long lasting gene expression changes in a well-established mouse model that is based on maternal treatment with the viral mimic poly(I:C) during pregnancy C57BL/6 mice were treated with the synthetic viral mimetic poly(I:C) (5 mg/kg, i.v.) or control (saline, i.v.) solution on gestation day 17. Offspring were subjected to cognitive and behavioral testing in adulthood, and then whole genome gene expression analysis with Affymetrix Microarray and subsequent q-PCR validation were performed on the nucleus accumbens.
Project description:DNA methylation profiling of nucleus Accumbens of rats that self administered cocaine, were subjected to 30 withdrawal days, were treated with aCSF, RG108 or SAM and were subjected to extinction tests. The groups consist of: 1. Rats that self-administered cocaine for 10 days and that were subjected to a withdrawal period of 30 days, were injected in the nucleus accumbens with aCSF and were subjected to an extinction test for assessment of cue-induced cocaine-seeking behavior (aCSF) 2. Rats that self-administered cocaine for 10 days and that were subjected to a withdrawal period of 30 days, were injected in the nucleus accumbens with RG108 and were subjected to an extinction test for assessment of cue-induced cocaine-seeking behavior (RG108) 3. Rats that self-administered cocaine for 10 days and that were subjected to a withdrawal period of 30 days, were injected in the nucleus accumbens with SAM and were subjected to an extinction test for assessment of cue-induced cocaine-seeking behavior (SAM)
Project description:The nucleus accumbens plays a central role in ther regulation of reward, emotion, motivation and goal-directed behavior. Gene expression impairments in this brain region are of crucial interest to understand the neurobiological underpinnings of heroin use disorder. We used the Affymetrix HG-U133A microarray to assess gene expression in the post-mortem nucleus accumbens of human heroin users and control subjects and identified differentially expressed genes.
Project description:Neuroanatomical methods enable high-resolution mapping of neural circuitry, but do not allow systematic molecular profiling of neurons based on their connectivity. Here, we report the development of a novel approach for molecularly profiling projective neurons. We show that ribosomes can be labeled with a camelid nanobody raised against GFP and that this system can be engineered to selectively capture translating mRNAs from cells expressing GFP. We generated a transgenic mouse encoding a nanobody-ribosomal protein fusion (Syn-NBL10) and used a retrograde virus (CAV) encoding GFP to immunoprecipitate ribosomes from projection neurons. This enabled us to profile neurons projecting to the nucleus accumbens. The current method provides a new means for profiling neurons based on their projections. Translating mRNAs immunoprecipitated from neurons projecting to the nucleus accumbens. Each Input and IP sample corrspond to a pooled group of 6 mice.
Project description:To identify distinct transcriptional patterns between the major subcortical dopamine targets commonly studied in addiction we studied differences in gene expression between the bed nucleus of the stria terminalis (BNST), nucleus accumbens (NAc), and dorsal striatum (dStr) using microarray analysis. We first tested for differences in expression of genes encoding transcripts for common neurotransmitter systems as well as calcium binding proteins routinely used in neuroanatomical delineation of brain regions. This a priori method revealed differential expression of corticotropin releasing hormone (Crh), the GABA transporter (Slc6a1), and prodynorphin (Pdyn) mRNAs as well as several others between. Using a Gene ontology tool, functional scoring analysis, and Ingenuity Pathway Analysis, we further identified several physiological pathways that were distinct among these brain regions. These two different analysis both identified calcium signaling, G-coupled protein receptor signaling, and adenylate cyclase-related signaling as significantly different among the BNST, NAc, and dStr. The results support other studies suggesting that crucial pathways involved in neurotransmission are distinct among the BNST, NAc, and dStr, and provide insight into the potential use of pharmacological agents that may target region-specific signaling pathways. Further, these studies provide a framework for future mouse-mouse comparisons of transcriptional profiles after behavioral/pharmacological manipulation. Genome-wide microarray was used to detect gene expression. Global functional profile, transcritional networks and canonical pathways were illustrated from the gene expression patterns. Experiment Overall Design: The genome-wide gene expression of mouse brain region bed nucleus of the stria terminalis, nucleus accumbens, and dorsal striatum were analyzed by Affymetrix Mouse430_2 chip. The expression and functional profiles were compared between these 3 tissues and cross-validated from independant data published before.