Lmo4 in the nucleus accumbens regulates cocaine sensitivity.
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ABSTRACT:
SUBMITTER: Lasek AW
PROVIDER: S-EPMC3130015 | biostudies-literature | 2010 Oct
REPOSITORIES: biostudies-literature
Publications
Lmo4 in the nucleus accumbens regulates cocaine sensitivity.
Lasek A W AW Kapfhamer D D Kharazia V V Gesch J J Giorgetti F F Heberlein U U
Genes, brain, and behavior 20100812 7
An estimated 2 million Americans use cocaine, resulting in large personal and societal costs. Discovery of the genetic factors that contribute to cocaine abuse is important for understanding this complex disease. Previously, mutations in the Drosophila LIM-only (dLmo) gene were identified because of their increased behavioral sensitivity to cocaine. Here we show that the mammalian homolog Lmo4, which is highly expressed in brain regions implicated in drug addiction, plays a similar role in cocai ...[more]
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Project description:Prior research demonstrated that environmental enrichment creates individual differences in behavior leading to a protective addiction phenotype in rats. Understanding the mechanisms underlying this phenotype will guide selection of targets for much-needed novel pharmacotherapeutics. The current study investigates basal differences in proteome expression in the nucleus accumbens of enriched and isolated rats and the proteomic response to cocaine self-administration using a liquid chromatography mass spectrometry (LCMS) technique to quantify 1917 proteins. Results of complementary Ingenuity Pathways Analyses (IPA) and gene set enrichment analyses (GSEA) demonstrate that cocaine increases vesicular transporters for dopamine and glutamate, as well as increasing proteins in the RhoA pathway. Further, cocaine regulates proteins related to ERK, CREB and AKT signaling. Environmental enrichment altered expression of a large number of proteins with diverse functions, including mood disorders, energy production, ubiquitination, splicing, transport, kinases and neurodegenerative diseases. Most of the biological functions and pathways listed above were also identified in the Cocaine X Enrichment interaction analysis, providing clear evidence that enriched and isolated rats respond quite differently to cocaine exposure. The overall impression of the current results is that enriched saline-administering rats have a unique proteomic complement compared to enriched cocaine-administering rats as well as saline and cocaine-taking isolated rats. These results identify possible mechanisms of the protective phenotype and provide fertile soil for developing novel pharmacotherapeutics.
2014-07-22 | PXD000990 | Pride
Project description:Natural antisense transcripts (NATs) are an abundant class of long noncoding RNAs that have recently been shown to be key regulators of chromatin dynamics and gene expression in nervous system development and neurological disorders. However, it is currently unclear if NAT-based mechanisms also play a role in drug-induced neuroadaptations. Aberrant regulation of gene expression is one critical factor underlying the long-lasting behavioral abnormalities that characterize substance use disorder, and it is possible that some drug-induced transcriptional responses are mediated, in part, by perturbations in NAT activity. To test this hypothesis, we used an automated algorithm that mines the NCBI AceView transcriptomics database to identify NAT overlapping genes linked to addiction. We found that 22% of the genes examined contain NATs and that expression of Homer1 natural antisense transcript (Homer1-AS) was altered in the nucleus accumbens (NAc) of mice 2h and 10days following repeated cocaine administration. In in vitro studies, depletion of Homer1-AS lead to an increase in the corresponding sense gene expression, indicating a potential regulatory mechanisms of Homer1 expression by its corresponding antisense transcript. Future in vivo studies are needed to definitely determine a role for Homer1-AS in cocaine-induced behavioral and molecular adaptations.
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