1 5449 94 REPRESSION OF THE ANTIOXIDANT NRF2 PATHWAY IN PREMATURE AGING. HUTCHINSON-GILFORD PROGERIA SYNDROME (HGPS) IS A RARE, INVARIABLY FATAL PREMATURE AGING DISORDER. THE DISEASE IS CAUSED BY CONSTITUTIVE PRODUCTION OF PROGERIN, A MUTANT FORM OF THE NUCLEAR ARCHITECTURAL PROTEIN LAMIN A, LEADING, THROUGH UNKNOWN MECHANISMS, TO DIVERSE MORPHOLOGICAL, EPIGENETIC, AND GENOMIC DAMAGE AND TO MESENCHYMAL STEM CELL (MSC) ATTRITION IN VIVO. USING A HIGH-THROUGHPUT SIRNA SCREEN, WE IDENTIFY THE NRF2 ANTIOXIDANT PATHWAY AS A DRIVER MECHANISM IN HGPS. PROGERIN SEQUESTERS NRF2 AND THEREBY CAUSES ITS SUBNUCLEAR MISLOCALIZATION, RESULTING IN IMPAIRED NRF2 TRANSCRIPTIONAL ACTIVITY AND CONSEQUENTLY INCREASED CHRONIC OXIDATIVE STRESS. SUPPRESSED NRF2 ACTIVITY OR INCREASED OXIDATIVE STRESS IS SUFFICIENT TO RECAPITULATE HGPS AGING DEFECTS, WHEREAS REACTIVATION OF NRF2 ACTIVITY IN HGPS PATIENT CELLS REVERSES PROGERIN-ASSOCIATED NUCLEAR AGING DEFECTS AND RESTORES IN VIVO VIABILITY OF MSCS IN AN ANIMAL MODEL. THESE FINDINGS IDENTIFY REPRESSION OF THE NRF2-MEDIATED ANTIOXIDATIVE RESPONSE AS A KEY CONTRIBUTOR TO THE PREMATURE AGING PHENOTYPE. 2016 2 3086 17 GENOME-WIDE TRANSCRIPTOMICS OF THE AMYGDALA REVEALS SIMILAR OLIGODENDROCYTE-RELATED RESPONSES TO ACUTE AND CHRONIC ALCOHOL DRINKING IN FEMALE MICE. REPEATED EXCESSIVE ALCOHOL CONSUMPTION IS A RISK FACTOR FOR ALCOHOL USE DISORDER (AUD). ALTHOUGH AUD HAS BEEN MORE COMMON IN MEN THAN WOMEN, WOMEN DEVELOP MORE SEVERE BEHAVIORAL AND PHYSICAL IMPAIRMENTS. HOWEVER, RELATIVELY FEW NEW THERAPEUTICS TARGETING DEVELOPMENT OF AUD, PARTICULARLY IN WOMEN, HAVE BEEN VALIDATED. TO GAIN A BETTER UNDERSTANDING OF MOLECULAR MECHANISMS UNDERLYING ALCOHOL INTAKE, WE CONDUCTED A GENOME-WIDE RNA-SEQUENCING ANALYSIS IN FEMALE MICE EXPOSED TO DIFFERENT MODES (ACUTE VS CHRONIC) OF ETHANOL DRINKING. WE FOCUSED ON TRANSCRIPTIONAL PROFILES IN THE AMYGDALA INCLUDING THE CENTRAL AND BASOLATERAL SUBNUCLEI, BRAIN AREAS PREVIOUSLY IMPLICATED IN ALCOHOL DRINKING AND SEEKING. SURPRISINGLY, WE FOUND THAT BOTH DRINKING MODES TRIGGERED SIMILAR CHANGES IN GENE EXPRESSION AND CANONICAL PATHWAYS, INCLUDING UPREGULATION OF RIBOSOME-RELATED/TRANSLATIONAL PATHWAYS AND MYELINATION PATHWAYS, AND DOWNREGULATION OF CHROMATIN BINDING AND HISTONE MODIFICATION. IN ADDITION, ANALYSES OF HUB GENES AND UPSTREAM REGULATORY PATHWAYS REVEALED THAT VOLUNTARY ETHANOL CONSUMPTION AFFECTS EPIGENETIC CHANGES VIA HISTONE DEACETYLATION PATHWAYS, OLIGODENDROCYTE AND MYELIN FUNCTION, AND THE OLIGODENDROCYTE-RELATED TRANSCRIPTION FACTOR, SOX17. FURTHERMORE, A VIRAL VECTOR-ASSISTED KNOCKDOWN OF SOX17 GENE EXPRESSION IN THE AMYGDALA PREVENTED A GRADUAL INCREASE IN ALCOHOL CONSUMPTION DURING REPEATED ACCESSES. OVERALL, THESE RESULTS SUGGEST THAT THE EXPRESSION OF OLIGODENDROCYTE-RELATED GENES IN THE AMYGDALA IS SENSITIVE TO VOLUNTARY ALCOHOL DRINKING IN FEMALE MICE. THESE FINDINGS SUGGEST POTENTIAL MOLECULAR TARGETS FOR FUTURE THERAPEUTIC APPROACHES TO PREVENT THE DEVELOPMENT OF AUD, DUE TO REPEATED EXCESSIVE ALCOHOL CONSUMPTION, PARTICULARLY IN WOMEN. 2022 3 4163 22 MECP2 REPRESSION OF G9A IN REGULATION OF PAIN AND MORPHINE REWARD. OPIOIDS ARE COMMONLY USED FOR PAIN RELIEF, BUT THEIR STRONG REWARDING EFFECTS DRIVE OPIOID MISUSE AND ABUSE. HOW PAIN AFFECTS THE LIABILITY OF OPIOID ABUSE IS UNKNOWN AT PRESENT. IN THIS STUDY, WE IDENTIFIED AN EPIGENETIC REGULATING CASCADE ACTIVATED BY BOTH PAIN AND THE OPIOID MORPHINE. BOTH PERSISTENT PAIN AND REPEATED MORPHINE UPREGULATED THE TRANSCRIPTIONAL REGULATOR MECP2 IN MOUSE CENTRAL NUCLEUS OF THE AMYGDALA (CEA). CHROMATIN IMMUNOPRECIPITATION ANALYSIS REVEALED THAT MECP2 BOUND TO AND REPRESSED THE TRANSCRIPTIONAL REPRESSOR HISTONE DIMETHYLTRANSFERASE G9A, REDUCING G9A-CATALYZED REPRESSIVE MARK H3K9ME2 IN CEA. REPRESSION OF G9A ACTIVITY INCREASED EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF). BEHAVIORALLY, PERSISTENT INFLAMMATORY PAIN INCREASED THE SENSITIVITY TO ACQUIRING MORPHINE-INDUCED, REWARD-RELATED BEHAVIOR OF CONDITIONED PLACE PREFERENCE IN MICE. LOCAL VIRAL VECTOR-MEDIATED MECP2 OVEREXPRESSION, CRE-INDUCED G9A KNOCKDOWN, AND CEA APPLICATION OF BDNF MIMICKED, WHEREAS MECP2 KNOCKDOWN INHIBITED, THE PAIN EFFECT. THESE RESULTS SUGGEST THAT MECP2 DIRECTLY REPRESSES G9A AS A SHARED MECHANISM IN CENTRAL AMYGDALA FOR REGULATION OF EMOTIONAL RESPONSES TO PAIN AND OPIOID REWARD, AND FOR THEIR BEHAVIORAL INTERACTION. 2014 4 2883 21 G9A INHIBITS CREB-TRIGGERED EXPRESSION OF MU OPIOID RECEPTOR IN PRIMARY SENSORY NEURONS FOLLOWING PERIPHERAL NERVE INJURY. NEUROPATHIC PAIN, A DISTRESSING AND DEBILITATING DISORDER, IS STILL POORLY MANAGED IN CLINIC. OPIOIDS, LIKE MORPHINE, REMAIN THE MAINSTAY OF PRESCRIBED MEDICATIONS IN THE TREATMENT OF THIS DISORDER, BUT THEIR ANALGESIC EFFECTS ARE HIGHLY UNSATISFACTORY IN PART DUE TO NERVE INJURY-INDUCED REDUCTION OF OPIOID RECEPTORS IN THE FIRST-ORDER SENSORY NEURONS OF DORSAL ROOT GANGLIA. G9A IS A REPRESSOR OF GENE EXPRESSION. WE FOUND THAT NERVE INJURY-INDUCED INCREASES IN G9A AND ITS CATALYZED REPRESSIVE MARKER H3K9M2 ARE RESPONSIBLE FOR EPIGENETIC SILENCING OF OPRM1, OPRK1, AND OPRD1 GENES IN THE INJURED DORSAL ROOT GANGLIA. BLOCKING THESE INCREASES RESCUED DORSAL ROOT GANGLIA OPRM1, OPRK1, AND OPRD1 GENE EXPRESSION AND MORPHINE OR LOPERAMIDE ANALGESIA AND PREVENTED THE DEVELOPMENT OF MORPHINE OR LOPERAMIDE-INDUCED ANALGESIC TOLERANCE UNDER NEUROPATHIC PAIN CONDITIONS. CONVERSELY, MIMICKING THESE INCREASES REDUCED THE EXPRESSION OF THREE OPIOID RECEPTORS AND PROMOTED THE MU OPIOID RECEPTOR-GATED RELEASE OF PRIMARY AFFERENT NEUROTRANSMITTERS. MECHANISTICALLY, NERVE INJURY-INDUCED INCREASES IN THE BINDING ACTIVITY OF G9A AND H3K9ME2 TO THE OPRM1 GENE WERE ASSOCIATED WITH THE REDUCED BINDING OF CYCLIC AMP RESPONSE ELEMENT BINDING PROTEIN TO THE OPRM1 GENE. THESE FINDINGS SUGGEST THAT G9A PARTICIPATES IN THE NERVE INJURY-INDUCED REDUCTION OF THE OPRM1 GENE LIKELY THROUGH G9A-TRIGGERED BLOCKAGE IN THE ACCESS OF CYCLIC AMP RESPONSE ELEMENT BINDING PROTEIN TO THIS GENE. 2016 5 69 23 A MEDIAL PREFRONTAL CORTEX-NUCLEUS ACUMENS CORTICOTROPIN-RELEASING FACTOR CIRCUITRY FOR NEUROPATHIC PAIN-INCREASED SUSCEPTIBILITY TO OPIOID REWARD. RECENT STUDIES HAVE SHOWN THAT PERSISTENT PAIN FACILITATES THE RESPONSE TO MORPHINE REWARD. HOWEVER, THE CIRCUIT MECHANISM UNDERLYING THIS PROCESS REMAINS AMBIGUOUS. IN THIS STUDY, USING CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE IN MICE, WE FOUND THAT PERSISTENT NEUROPATHIC PAIN REDUCED THE MINIMUM NUMBER OF MORPHINE CONDITIONING SESSIONS REQUIRED TO INDUCE CONDITIONED PLACE PREFERENCE (CPP) BEHAVIOR. THIS DOSE OF MORPHINE HAD NO EFFECT ON THE PAIN THRESHOLD. IN THE MEDIAL PREFRONTAL CORTEX (MPFC), WHICH IS INVOLVED IN BOTH PAIN AND EMOTION PROCESSING, CORTICOTROPIN-RELEASING FACTOR (CRF) EXPRESSING NEURONAL ACTIVITY WAS INCREASED IN CCI MICE. CHEMOGENETIC INHIBITION OF MPFC CRF NEURONS REVERSED CCI-INDUCED MORPHINE CPP FACILITATION. FURTHERMORE, THE NUCLEUS ACUMENS (NAC) RECEIVED MPFC CRF FUNCTIONAL PROJECTIONS THAT EXERTED EXCITATORY EFFECTS ON NAC NEURONS. OPTOGENETIC INHIBITION OF MPCF NEURONAL TERMINALS OR LOCAL INFUSION OF THE CRF RECEPTOR 1 (CRFR1) ANTAGONIST IN THE NAC RESTORED THE EFFECTS OF NEUROPATHIC PAIN ON MORPHINE-INDUCED CPP BEHAVIOR, BUT NOT IN NORMAL MICE. ON A MOLECULAR LEVEL, IN CCI MICE, CRFR1 PROTEIN EXPRESSION WAS INCREASED IN THE NAC BY A HISTONE DIMETHYLTRANSFERASE G9A-MEDIATED EPIGENETIC MECHANISM. LOCAL G9A KNOCKDOWN INCREASED THE EXPRESSION OF CRFR1 AND MIMICKED CCI-INDUCED HYPERSENSITIVITY TO ACQUIRING MORPHINE CPP. TAKEN TOGETHER, THESE FINDINGS DEMONSTRATE A PREVIOUSLY UNKNOWN AND SPECIFIC MPFC CRF ENGAGEMENT OF NAC NEURONAL CIRCUITS, THE SENSITIZATION OF WHICH FACILITATES BEHAVIORAL RESPONSES TO MORPHINE REWARD IN NEUROPATHIC PAIN STATES VIA CRFR1S. 2018 6 6177 14 THE HISTONE METHYLTRANSFERASE G9A MEDIATES STRESS-REGULATED ALCOHOL DRINKING. THE EPIGENETIC ENZYME G9A IS A HISTONE METHYLTRANSFERASE THAT DIMETHYLATES LYSINE 9 ON HISTONE H3 (H3K9ME2), AND IN THE ADULT NUCLEUS ACCUMBENS (NAC), G9A REGULATES MULTIPLE BEHAVIORS ASSOCIATED WITH SUBSTANCE USE DISORDER. WE SHOW HERE THAT CHRONIC INTERMITTENT ETHANOL (CIE) EXPOSURE IN MALE MICE REDUCED BOTH G9A AND H3K9ME2 LEVELS IN THE ADULT NAC, BUT NOT DORSAL STRIATUM. VIRAL-MEDIATED REDUCTION OF G9A IN THE NAC HAD NO EFFECTS ON BASELINE VOLITIONAL ETHANOL DRINKING OR ESCALATED ALCOHOL DRINKING PRODUCED BY CIE EXPOSURE; HOWEVER, NAC G9A WAS REQUIRED FOR STRESS-REGULATED CHANGES IN ETHANOL DRINKING, INCLUDING POTENTIATED ALCOHOL DRINKING PRODUCED BY ACTIVATION OF THE KAPPA-OPIOID RECEPTOR. IN ADDITION, WE OBSERVED THAT CHRONIC SYSTEMIC ADMINISTRATION OF A G9A INHIBITOR, UNC0642, ALSO BLOCKED STRESS-POTENTIATED ALCOHOL DRINKING. TOGETHER, OUR FINDINGS SUGGEST THAT CHRONIC ALCOHOL USE, SIMILAR TO OTHER ABUSED SUBSTANCES, PRODUCES A NAC-SELECTIVE REDUCTION IN G9A LEVELS THAT SERVES TO LIMIT STRESS-REGULATED ALCOHOL DRINKING. MOREOVER, OUR FINDINGS SUGGEST THAT PHARMACOLOGICAL INHIBITION OF G9A MIGHT PROVIDE A NOVEL THERAPEUTIC APPROACH TO TREAT STRESS-INDUCED ALCOHOL DRINKING, WHICH IS A MAJOR TRIGGER OF RELAPSE IN INDIVIDUALS SUFFERING FROM AUD. 2022 7 1416 19 DIETARY POLYPHENOLS REMODEL DNA METHYLATION PATTERNS OF NRF2 IN CHRONIC DISEASE. THE NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR 2 (NRF2) IS A TRANSCRIPTION FACTOR CRUCIAL IN REGULATING CELLULAR HOMEOSTASIS AND APOPTOSIS. THE NRF2 GENE HAS BEEN IMPLICATED IN VARIOUS BIOLOGICAL ACTIVITIES, INCLUDING ANTIOXIDANT, ANTI-INFLAMMATORY, AND ANTICANCER PROPERTIES. NRF2 CAN BE REGULATED GENETICALLY AND EPIGENETICALLY AT THE TRANSCRIPTIONAL, POST-TRANSCRIPTIONAL, AND TRANSLATIONAL LEVELS. ALTHOUGH DNA METHYLATION IS ONE OF THE CRITICAL BIOLOGICAL PROCESSES VITAL FOR GENE EXPRESSION, SOMETIMES, ANOMALOUS METHYLATION PATTERNS RESULT IN THE DYSREGULATION OF GENES AND CONSEQUENT DISEASES AND DISORDERS. SEVERAL STUDIES HAVE REPORTED PROMOTER HYPERMETHYLATION DOWNREGULATED NRF2 EXPRESSION AND ITS DOWNSTREAM TARGETS. IN CONTRAST TO THE UNALTERABLE NATURE OF GENETIC PATTERNS, EPIGENETIC CHANGES CAN BE REVERSED, OPENING UP NEW POSSIBILITIES IN DEVELOPING THERAPIES FOR VARIOUS METABOLIC DISORDERS AND DISEASES. THIS REVIEW DISCUSSES THE CURRENT STATE OF THE NRF2-MEDIATED ANTIOXIDATIVE AND CHEMOPREVENTIVE ACTIVITIES OF SEVERAL NATURAL PHYTOCHEMICALS, INCLUDING SULFORAPHANE, RESVERATROL, CURCUMIN, LUTEOLIN, COROSOLIC ACID, APIGENIN, AND MOST OTHER COMPOUNDS THAT HAVE BEEN FOUND TO ACTIVATE NRF2. THIS EPIGENETIC REVERSAL OF HYPERMETHYLATED NRF2 STATES PROVIDES NEW OPPORTUNITIES FOR RESEARCH INTO DIETARY PHYTOCHEMISTRY THAT AFFECTS THE HUMAN EPIGENOME AND THE POSSIBILITY FOR CUTTING-EDGE APPROACHES TO TARGET NRF2-MEDIATED SIGNALING TO PREVENT CHRONIC DISORDERS. 2023 8 4761 24 NRF2 SENSITIZES FERROPTOSIS THROUGH L-2-HYDROXYGLUTARATE-MEDIATED CHROMATIN MODIFICATIONS IN SICKLE CELL DISEASE. SICKLE CELL DISEASE (SCD) IS A CHRONIC HEMOLYTIC AND SYSTEMIC HYPOXIA CONDITION WITH CONSTANT OXIDATIVE STRESS AND SIGNIFICANT METABOLIC ALTERATIONS. HOWEVER, LITTLE IS KNOWN ABOUT THE CORRELATION BETWEEN METABOLIC ALTERATIONS AND THE PATHOPHYSIOLOGICAL SYMPTOMS. HERE, WE REPORT THAT NRF2, A MASTER REGULATOR OF CELLULAR ANTIOXIDANT RESPONSES, REGULATES THE PRODUCTION OF THE METABOLITE L-2-HYDROXYGLUTARATE (L2HG) TO MEDIATE EPIGENETIC HISTONE HYPERMETHYLATION FOR GENE EXPRESSION INVOLVED IN METABOLIC, OXIDATIVE, AND FERROPTOTIC STRESS RESPONSES IN SCD. MECHANISTICALLY, NRF2 WAS FOUND TO REGULATE THE EXPRESSION OF L2HG DEHYDROGENASE (L2HGDH) TO MEDIATE L2HG PRODUCTION UNDER HYPOXIA. GENE EXPRESSION PROFILE ANALYSIS INDICATED THAT REACTIVE OXYGEN SPECIES (ROS) AND FERROPTOSIS RESPONSES WERE THE MOST SIGNIFICANTLY AFFECTED SIGNALING PATHWAYS AFTER NRF2 ABLATION IN SCD. NRF2 SILENCING AND L2HG SUPPLEMENTATION SENSITIZE HUMAN SICKLE ERYTHROID CELLS TO ROS AND FERROPTOSIS STRESS. THE ABSENCE OF NRF2 AND ACCUMULATION OF L2HG SIGNIFICANTLY AFFECT HISTONE METHYLATION FOR CHROMATIN STRUCTURE MODIFICATION AND REDUCE THE ASSEMBLY OF TRANSCRIPTION COMPLEXES ON DOWNSTREAM TARGET GENES TO REGULATE ROS AND FERROPTOSIS RESPONSES. FURTHERMORE, PHARMACOLOGICAL ACTIVATION OF NRF2 WAS FOUND TO HAVE PROTECTIVE EFFECTS AGAINST ROS AND FERROPTOSIS STRESS IN SCD MICE. OUR DATA SUGGEST A NOVEL MECHANISM BY WHICH NRF2 REGULATES L2HG LEVELS TO MEDIATE SCD SEVERITY THROUGH ROS AND FERROPTOSIS STRESS RESPONSES, SUGGESTING THAT TARGETING NRF2 IS A VIABLE THERAPEUTIC STRATEGY FOR AMELIORATING SCD SYMPTOMS. 2023 9 657 22 BLOCKING THE SPINAL FBXO3/CARM1/K(+) CHANNEL EPIGENETIC SILENCING PATHWAY AS A STRATEGY FOR NEUROPATHIC PAIN RELIEF. MANY EPIGENETIC REGULATORS ARE INVOLVED IN PAIN-ASSOCIATED SPINAL PLASTICITY. COACTIVATOR-ASSOCIATED ARGININE METHYLTRANSFERASE 1 (CARM1), AN EPIGENETIC REGULATOR OF HISTONE ARGININE METHYLATION, IS A HIGHLY INTERESTING TARGET IN NEUROPLASTICITY. HOWEVER, ITS POTENTIAL CONTRIBUTION TO SPINAL PLASTICITY-ASSOCIATED NEUROPATHIC PAIN DEVELOPMENT REMAINS POORLY EXPLORED. HERE, WE REPORT THAT NERVE INJURY DECREASED THE EXPRESSION OF SPINAL CARM1 AND INDUCED ALLODYNIA. MOREOVER, DECREASING SPINAL CARM1 EXPRESSION BY FBXO3-MEDIATED CARM1 UBIQUITINATION PROMOTED H3R17ME2 DECREMENT AT THE K(+) CHANNEL PROMOTER, THEREBY CAUSING K(+) CHANNEL EPIGENETIC SILENCING AND THE DEVELOPMENT OF NEUROPATHIC PAIN. REMARKABLY, IN NAIVE RATS, DECREASING SPINAL CARM1 USING CARM1 SIRNA OR A CARM1 INHIBITOR RESULTED IN SIMILAR EPIGENETIC SIGNALING AND ALLODYNIA. FURTHERMORE, INTRATHECAL ADMINISTRATION OF BC-1215 (A NOVEL FBXO3 INHIBITOR) PREVENTED CARM1 UBIQUITINATION TO BLOCK K(+) CHANNEL GENE SILENCING AND AMELIORATE ALLODYNIA AFTER NERVE INJURY. COLLECTIVELY, THE RESULTS REVEAL THAT THIS NEWLY IDENTIFIED SPINAL FBXO3-CARM1-K(+) CHANNEL GENE FUNCTIONAL AXIS PROMOTES NEUROPATHIC PAIN. THESE FINDINGS PROVIDE ESSENTIAL INSIGHTS THAT WILL AID IN THE DEVELOPMENT OF MORE EFFICIENT AND SPECIFIC THERAPIES AGAINST NEUROPATHIC PAIN. 2021 10 5354 21 RE1-SILENCING TRANSCRIPTION FACTOR CONTROLS THE ACUTE-TO-CHRONIC NEUROPATHIC PAIN TRANSITION AND CHRM2 RECEPTOR GENE EXPRESSION IN PRIMARY SENSORY NEURONS. NEUROPATHIC PAIN IS ASSOCIATED WITH PERSISTENT CHANGES IN GENE EXPRESSION IN PRIMARY SENSORY NEURONS, BUT THE UNDERLYING EPIGENETIC MECHANISMS THAT CAUSE THESE CHANGES REMAIN UNCLEAR. THE MUSCARINIC CHOLINERGIC RECEPTORS (MACHRS), PARTICULARLY THE M2 SUBTYPE (ENCODED BY THE CHOLINERGIC RECEPTOR MUSCARINIC 2 (CHRM2) GENE), ARE CRITICALLY INVOLVED IN THE REGULATION OF SPINAL NOCICEPTIVE TRANSMISSION. HOWEVER, LITTLE IS KNOWN ABOUT HOW CHRM2 EXPRESSION IS TRANSCRIPTIONALLY REGULATED. HERE WE SHOW THAT NERVE INJURY PERSISTENTLY INCREASED THE EXPRESSION OF RE1-SILENCING TRANSCRIPTION FACTOR (REST, ALSO KNOWN AS NEURON-RESTRICTIVE SILENCING FACTOR [NRSF]), A GENE-SILENCING TRANSCRIPTION FACTOR, IN THE DORSAL ROOT GANGLION (DRG). REMARKABLY, NERVE INJURY-INDUCED CHRONIC BUT NOT ACUTE PAIN HYPERSENSITIVITY WAS ATTENUATED IN MICE WITH REST KNOCKOUT IN DRG NEURONS. ALSO, SIRNA-MEDIATED REST KNOCKDOWN REVERSED NERVE INJURY-INDUCED CHRONIC PAIN HYPERSENSITIVITY IN RATS. NERVE INJURY PERSISTENTLY REDUCED CHRM2 EXPRESSION IN THE DRG AND DIMINISHED THE ANALGESIC EFFECT OF MUSCARINE. THE RE1 BINDING SITE ON THE CHRM2 PROMOTER IS REQUIRED FOR REST-MEDIATED CHRM2 REPRESSION, AND NERVE INJURY INCREASED THE ENRICHMENT OF REST IN THE CHRM2 PROMOTER IN THE DRG. FURTHERMORE, REST KNOCKDOWN OR GENETIC ABLATION IN DRG NEURONS NORMALIZED CHRM2 EXPRESSION AND AUGMENTED MUSCARINE'S ANALGESIC EFFECT ON NEUROPATHIC PAIN AND FULLY REVERSED THE NERVE INJURY-INDUCED REDUCTION IN THE INHIBITORY EFFECT OF MUSCARINE ON GLUTAMATERGIC INPUT TO SPINAL DORSAL HORN NEURONS. OUR FINDINGS INDICATE THAT NERVE INJURY-INDUCED REST UP-REGULATION IN DRG NEURONS PLAYS AN IMPORTANT ROLE IN THE ACUTE-TO-CHRONIC PAIN TRANSITION AND IS ESSENTIAL FOR THE TRANSCRIPTIONAL REPRESSION OF CHRM2 IN NEUROPATHIC PAIN. 2018 11 4603 27 NEGATIVE ALLOSTERIC MODULATION OF MGLUR5 PARTIALLY CORRECTS PATHOPHYSIOLOGY IN A MOUSE MODEL OF RETT SYNDROME. RETT SYNDROME (RTT) IS CAUSED BY MUTATIONS IN THE GENE ENCODING METHYL-CPG BINDING PROTEIN 2 (MECP2), AN EPIGENETIC REGULATOR OF MRNA TRANSCRIPTION. HERE, WE REPORT A TEST OF THE HYPOTHESIS OF SHARED PATHOPHYSIOLOGY OF RTT AND FRAGILE X, ANOTHER MONOGENIC CAUSE OF AUTISM AND INTELLECTUAL DISABILITY. IN FRAGILE X, THE LOSS OF THE MRNA TRANSLATIONAL REPRESSOR FMRP LEADS TO EXAGGERATED PROTEIN SYNTHESIS DOWNSTREAM OF METABOTROPIC GLUTAMATE RECEPTOR 5 (MGLUR5). WE FOUND THAT MGLUR5- AND PROTEIN-SYNTHESIS-DEPENDENT SYNAPTIC PLASTICITY WERE SIMILARLY ALTERED IN AREA CA1 OF MECP2 KO MICE. CA1 PYRAMIDAL CELL-TYPE-SPECIFIC, GENOME-WIDE PROFILING OF RIBOSOME-BOUND MRNAS WAS PERFORMED IN WILD-TYPE AND MECP2 KO HIPPOCAMPAL CA1 NEURONS TO REVEAL THE MECP2-REGULATED "TRANSLATOME." WE FOUND SIGNIFICANT OVERLAP BETWEEN RIBOSOME-BOUND TRANSCRIPTS OVEREXPRESSED IN THE MECP2 KO AND FMRP MRNA TARGETS. THESE TENDED TO ENCODE LONG GENES THAT WERE FUNCTIONALLY RELATED TO EITHER CYTOSKELETON ORGANIZATION OR THE DEVELOPMENT OF NEURONAL CONNECTIVITY. IN THE FMR1 KO MOUSE, CHRONIC TREATMENT WITH MGLUR5-NEGATIVE ALLOSTERIC MODULATORS (NAMS) HAS BEEN SHOWN TO AMELIORATE MANY MUTANT PHENOTYPES BY CORRECTING EXCESSIVE PROTEIN SYNTHESIS. IN MECP2 KO MICE, WE FOUND THAT MGLUR5 NAM TREATMENT SIGNIFICANTLY REDUCED THE LEVEL OF OVEREXPRESSED RIBOSOME-ASSOCIATED TRANSCRIPTS, PARTICULARLY THOSE THAT WERE ALSO FMRP TARGETS. SOME RETT PHENOTYPES WERE ALSO AMELIORATED BY TREATMENT, MOST NOTABLY HIPPOCAMPAL CELL SIZE AND LIFESPAN. TOGETHER, THESE RESULTS SUGGEST A POTENTIAL MECHANISTIC LINK BETWEEN MECP2-MEDIATED TRANSCRIPTION REGULATION AND MGLUR5/FMRP-MEDIATED PROTEIN TRANSLATION REGULATION THROUGH COREGULATION OF A SUBSET OF GENES RELEVANT TO SYNAPTIC FUNCTIONS. SIGNIFICANCE STATEMENT: ALTERED REGULATION OF SYNAPTIC PROTEIN SYNTHESIS HAS BEEN HYPOTHESIZED TO CONTRIBUTE TO THE PATHOPHYSIOLOGY THAT UNDERLIES MULTIPLE FORMS OF INTELLECTUAL DISABILITY AND AUTISM SPECTRUM DISORDER. HERE, WE SHOW IN A MOUSE MODEL OF RETT SYNDROME (MECP2 KO) THAT METABOTROPIC GLUTAMATE RECEPTOR 5 (MGLUR5)- AND PROTEIN-SYNTHESIS-DEPENDENT SYNAPTIC PLASTICITY ARE ABNORMAL IN THE HIPPOCAMPUS. WE FOUND THAT A SUBSET OF RIBOSOME-BOUND MRNAS WAS ABERRANTLY UPREGULATED IN HIPPOCAMPAL CA1 NEURONS OF MECP2 KO MICE, THAT THESE SIGNIFICANTLY OVERLAPPED WITH FMRP DIRECT TARGETS AND/OR SFARI HUMAN AUTISM GENES, AND THAT CHRONIC TREATMENT OF MECP2 KO MICE WITH AN MGLUR5-NEGATIVE ALLOSTERIC MODULATOR TUNES DOWN UPREGULATED RIBOSOME-BOUND MRNAS AND PARTIALLY IMPROVES MUTANT MICE PHENOTYPES. 2016 12 856 21 CHROMATIN ACCESSIBILITY MAPPING OF THE STRIATUM IDENTIFIES TYROSINE KINASE FYN AS A THERAPEUTIC TARGET FOR HEROIN USE DISORDER. THE CURRENT OPIOID EPIDEMIC NECESSITATES A BETTER UNDERSTANDING OF HUMAN ADDICTION NEUROBIOLOGY TO DEVELOP EFFICACIOUS TREATMENT APPROACHES. HERE, WE PERFORM GENOME-WIDE ASSESSMENT OF CHROMATIN ACCESSIBILITY OF THE HUMAN STRIATUM IN HEROIN USERS AND MATCHED CONTROLS. OUR STUDY REVEALS DISTINCT NEURONAL AND NON-NEURONAL EPIGENETIC SIGNATURES, AND IDENTIFIES A LOCUS IN THE PROXIMITY OF THE GENE ENCODING TYROSINE KINASE FYN AS THE MOST AFFECTED REGION IN NEURONS. FYN EXPRESSION, KINASE ACTIVITY AND THE PHOSPHORYLATION OF ITS TARGET TAU ARE INCREASED BY HEROIN USE IN THE POST-MORTEM HUMAN STRIATUM, AS WELL AS IN RATS TRAINED TO SELF-ADMINISTER HEROIN AND PRIMARY STRIATAL NEURONS TREATED WITH CHRONIC MORPHINE IN VITRO. PHARMACOLOGICAL OR GENETIC MANIPULATION OF FYN ACTIVITY SIGNIFICANTLY ATTENUATES HEROIN SELF-ADMINISTRATION AND RESPONDING FOR DRUG-PAIRED CUES IN RODENTS. OUR FINDINGS SUGGEST THAT STRIATAL FYN IS AN IMPORTANT DRIVER OF HEROIN-RELATED NEURODEGENERATIVE-LIKE PATHOLOGY AND DRUG-TAKING BEHAVIOR, MAKING FYN A PROMISING THERAPEUTIC TARGET FOR HEROIN USE DISORDER. 2020 13 3894 15 LAMIN B1 REGULATES SOMATIC MUTATIONS AND PROGRESSION OF B-CELL MALIGNANCIES. SOMATIC HYPERMUTATION (SHM) IS A PIVOTAL PROCESS IN ADAPTIVE IMMUNITY THAT OCCURS IN THE GERMINAL CENTRE AND ALLOWS B CELLS TO CHANGE THEIR PRIMARY DNA SEQUENCE AND DIVERSIFY THEIR ANTIGEN RECEPTORS. HERE, WE REPORT THAT GENOME BINDING OF LAMIN B1, A COMPONENT OF THE NUCLEAR ENVELOPE INVOLVED IN EPIGENETIC CHROMATIN REGULATION, IS REDUCED DURING B-CELL ACTIVATION AND FORMATION OF LYMPHOID GERMINAL CENTRES. CHROMATIN IMMUNOPRECIPITATION-SEQ ANALYSIS SHOWED THAT KAPPA AND HEAVY VARIABLE IMMUNOGLOBULIN DOMAINS WERE RELEASED FROM THE LAMIN B1 SUPPRESSIVE ENVIRONMENT WHEN SHM WAS INDUCED IN B CELLS. RNA INTERFERENCE-MEDIATED REDUCTION OF LAMIN B1 RESULTED IN SPONTANEOUS SHM AS WELL AS KAPPA-LIGHT CHAIN ABERRANT SURFACE EXPRESSION. FINALLY, LAMIN B1 EXPRESSION LEVEL CORRELATED WITH PROGRESSION-FREE AND OVERALL SURVIVAL IN CHRONIC LYMPHOCYTIC LEUKAEMIA, AND WAS STRONGLY INVOLVED IN THE TRANSFORMATION OF FOLLICULAR LYMPHOMA. IN SUMMARY, HERE WE REPORT THAT LAMIN B1 IS A NEGATIVE EPIGENETIC REGULATOR OF SHM IN NORMAL B-CELLS AND A 'MUTATIONAL GATEKEEPER', SUPPRESSING THE ABERRANT MUTATIONS THAT DRIVE LYMPHOID MALIGNANCY. 2018 14 4498 22 MORPHINE REGULATES ARGONAUTE 2 AND TH EXPRESSION AND ACTIVITY BUT NOT MIR-133B IN MIDBRAIN DOPAMINERGIC NEURONS. EPIGENETIC CHANGES SUCH AS MICRORNAS (MIRS)/AGO2-INDUCED GENE SILENCING REPRESENT COMPLEX MOLECULAR SIGNATURE THAT REGULATE CELLULAR PLASTICITY. RECENT STUDIES SHOWED INVOLVEMENT OF MIRS AND AGO2 IN DRUG ADDICTION. IN THIS STUDY, WE SHOW THAT CHANGES IN GENE EXPRESSION INDUCED BY MORPHINE AND MORPHINE WITHDRAWAL OCCUR WITH CONCOMITANT EPIGENETIC MODIFICATIONS IN THE MESOLIMBIC DOPAMINERGIC (DA) PATHWAY [VENTRAL TEGMENTAL AREA (VTA)/NUCLEUS ACCUMBENS (NAC) SHELL], WHICH IS CRITICALLY INVOLVED IN DRUG-INDUCED DEPENDENCE. WE FOUND THAT ACUTE OR CHRONIC MORPHINE ADMINISTRATION AS WELL AS MORPHINE WITHDRAWAL DID NOT MODIFY MIR-133B MESSENGER RNA (MRNA) EXPRESSION IN THE VTA, WHEREAS AGO2 PROTEIN LEVELS WERE DECREASED AND INCREASED IN MORPHINE-DEPENDENT RATS AND AFTER MORPHINE WITHDRAWAL, RESPECTIVELY. THESE CHANGES WERE PARALLELED WITH ENHANCED AND DECREASED NAC TYROSINE HYDROXYLASE (TH) PROTEIN (AN EARLY DA MARKER) IN MORPHINE-DEPENDENT RATS AND AFTER WITHDRAWAL, RESPECTIVELY. WE ALSO OBSERVED CHANGES IN TH MRNA EXPRESSION IN THE VTA THAT COULD BE RELATED TO AGO2-INDUCED TRANSLATIONAL REPRESSION OF TH MRNA DURING MORPHINE WITHDRAWAL. HOWEVER, THE VTA NUMBER OF TH-POSITIVE NEURONS SUFFERED NO ALTERATIONS AFTER THE DIFFERENT TREATMENT. ACUTE MORPHINE ADMINISTRATION PRODUCED A MARKED INCREASE IN TH ACTIVITY AND DA TURNOVER IN THE NAC (SHELL). IN CONTRAST, PRECIPITATED MORPHINE WITHDRAWAL DECREASED TH ACTIVATION AND DID NOT CHANGE DA TURNOVER. THESE FINDINGS PROVIDE NEW INFORMATION INTO THE POSSIBLE CORRELATION BETWEEN AGO2/MIRS COMPLEX REGULATION AND DA NEURONS PLASTICITY DURING OPIATE ADDICTION. 2015 15 2358 26 EPIGENETIC REGULATION OF RAC1 INDUCES SYNAPTIC REMODELING IN STRESS DISORDERS AND DEPRESSION. DEPRESSION INDUCES STRUCTURAL AND FUNCTIONAL SYNAPTIC PLASTICITY IN BRAIN REWARD CIRCUITS, ALTHOUGH THE MECHANISMS PROMOTING THESE CHANGES AND THEIR RELEVANCE TO BEHAVIORAL OUTCOMES ARE UNKNOWN. TRANSCRIPTIONAL PROFILING OF THE NUCLEUS ACCUMBENS (NAC) FOR RHO GTPASE-RELATED GENES, WHICH ARE KNOWN REGULATORS OF SYNAPTIC STRUCTURE, REVEALED A SUSTAINED REDUCTION IN RAS-RELATED C3 BOTULINUM TOXIN SUBSTRATE 1 (RAC1) EXPRESSION AFTER CHRONIC SOCIAL DEFEAT STRESS. THIS WAS ASSOCIATED WITH A REPRESSIVE CHROMATIN STATE SURROUNDING THE PROXIMAL PROMOTER OF RAC1. INHIBITION OF CLASS 1 HISTONE DEACETYLASES (HDACS) WITH MS-275 RESCUED BOTH THE DECREASE IN RAC1 TRANSCRIPTION AFTER SOCIAL DEFEAT STRESS AND DEPRESSION-RELATED BEHAVIOR, SUCH AS SOCIAL AVOIDANCE. WE FOUND A SIMILAR REPRESSIVE CHROMATIN STATE SURROUNDING THE RAC1 PROMOTER IN THE NAC OF SUBJECTS WITH DEPRESSION, WHICH CORRESPONDED WITH REDUCED RAC1 TRANSCRIPTION. VIRAL-MEDIATED REDUCTION OF RAC1 EXPRESSION OR INHIBITION OF RAC1 ACTIVITY IN THE NAC INCREASES SOCIAL DEFEAT-INDUCED SOCIAL AVOIDANCE AND ANHEDONIA IN MICE. CHRONIC SOCIAL DEFEAT STRESS INDUCES THE FORMATION OF STUBBY EXCITATORY SPINES THROUGH A RAC1-DEPENDENT MECHANISM INVOLVING THE REDISTRIBUTION OF SYNAPTIC COFILIN, AN ACTIN-SEVERING PROTEIN DOWNSTREAM OF RAC1. OVEREXPRESSION OF CONSTITUTIVELY ACTIVE RAC1 IN THE NAC OF MICE AFTER CHRONIC SOCIAL DEFEAT STRESS REVERSES DEPRESSION-RELATED BEHAVIORS AND PRUNES STUBBY SPINES. TAKEN TOGETHER, OUR DATA IDENTIFY EPIGENETIC REGULATION OF RAC1 IN THE NAC AS A DISEASE MECHANISM IN DEPRESSION AND REVEAL A FUNCTIONAL ROLE FOR RAC1 IN RODENTS IN REGULATING STRESS-RELATED BEHAVIORS. 2013 16 5021 19 PERSISTENT PAIN MAINTAINS MORPHINE-SEEKING BEHAVIOR AFTER MORPHINE WITHDRAWAL THROUGH REDUCED MECP2 REPRESSION OF GLUA1 IN RAT CENTRAL AMYGDALA. AS LONG-TERM OPIOIDS ARE INCREASINGLY USED FOR CONTROL OF CHRONIC PAIN, HOW PAIN AFFECTS THE REWARDING EFFECT OF OPIOIDS AND HENCE RISK OF PRESCRIPTION OPIOID MISUSE AND ABUSE REMAINS A HEALTHCARE CONCERN AND A CHALLENGING ISSUE IN CURRENT PAIN MANAGEMENT. IN THIS STUDY, USING A RAT MODEL OF MORPHINE SELF-ADMINISTRATION, WE INVESTIGATED THE MOLECULAR MECHANISMS UNDERLYING THE IMPACT OF PAIN ON OPERANT BEHAVIOR OF MORPHINE INTAKE AND MORPHINE SEEKING BEFORE AND AFTER MORPHINE WITHDRAWAL. WE FOUND THAT RATS WITH PERSISTENT PAIN CONSUMED A SIMILAR AMOUNT OF DAILY MORPHINE TO THAT IN CONTROL RATS WITHOUT PAIN, BUT MAINTAINED THEIR LEVEL-PRESSING BEHAVIOR OF MORPHINE SEEKING AFTER ABSTINENCE OF MORPHINE AT 0.2 MG/KG, WHEREAS THIS BEHAVIOR WAS GRADUALLY DIMINISHED IN CONTROL RATS. IN THE CENTRAL NUCLEUS OF AMYGDALA (CEA), A LIMBIC STRUCTURE CRITICALLY INVOLVED IN THE AFFECTIVE DIMENSION OF PAIN, PROTEINS OF GLUA1 SUBUNITS OF GLUTAMATE AMPA RECEPTORS WERE UPREGULATED DURING MORPHINE WITHDRAWAL, AND VIRAL KNOCKDOWN OF CEA GLUA1 ELIMINATED THE MORPHINE-SEEKING BEHAVIOR IN WITHDRAWN RATS OF THE PAIN GROUP. CHROMATIN IMMUNOPRECIPITATION ANALYSIS REVEALED THAT THE METHYL CPG-BINDING PROTEIN 2 (MECP2) WAS ENRICHED IN THE PROMOTER REGION OF GRIA1 ENCODING GLUA1 AND THIS ENRICHMENT WAS SIGNIFICANTLY ATTENUATED IN WITHDRAWN RATS OF THE PAIN GROUP. FURTHERMORE, VIRAL OVEREXPRESSION OF CEA MECP2 REPRESSED THE GLUA1 LEVEL AND ELIMINATED THE MAINTENANCE OF MORPHINE-SEEKING BEHAVIOR AFTER MORPHINE WITHDRAWAL. THESE RESULTS SUGGEST DIRECT MECP2 REPRESSION OF GLUA1 FUNCTION AS A LIKELY MECHANISM FOR MORPHINE-SEEKING BEHAVIOR MAINTAINED BY LONG-LASTING AFFECTIVE PAIN AFTER MORPHINE WITHDRAWAL. 2015 17 6424 23 THE TRANSCRIPTION FACTOR C/EBPBETA IN THE DORSAL ROOT GANGLION CONTRIBUTES TO PERIPHERAL NERVE TRAUMA-INDUCED NOCICEPTIVE HYPERSENSITIVITY. CHANGES IN GENE TRANSCRIPTION IN THE DORSAL ROOT GANGLION (DRG) AFTER NERVE TRAUMA CONTRIBUTE TO THE GENESIS OF NEUROPATHIC PAIN. WE REPORT THAT PERIPHERAL NERVE TRAUMA CAUSED BY CHRONIC CONSTRICTION INJURY (CCI) INCREASED THE ABUNDANCE OF THE TRANSCRIPTION FACTOR C/EBPBETA (CCAAT/ENHANCER BINDING PROTEIN BETA) IN THE DRG. BLOCKING THIS INCREASE MITIGATED THE DEVELOPMENT AND MAINTENANCE OF CCI-INDUCED MECHANICAL, THERMAL, AND COLD PAIN HYPERSENSITIVITIES WITHOUT AFFECTING BASAL RESPONSES TO ACUTE PAIN AND LOCOMOTOR ACTIVITY. CONVERSELY, MIMICKING THIS INCREASE PRODUCED HYPERSENSITIVITY TO MECHANICAL, THERMAL, OR COLD PAIN. IN THE IPSILATERAL DRG, C/EBPBETA PROMOTED A DECREASE IN THE ABUNDANCE OF THE VOLTAGE-GATED POTASSIUM CHANNEL SUBUNIT KV1.2 AND MU OPIOID RECEPTOR (MOR) AT THE MRNA AND PROTEIN LEVELS, WHICH WOULD BE PREDICTED TO INCREASE EXCITABILITY IN THE IPSILATERAL DRG NEURONS AND REDUCE THE EFFICACY OF MORPHINE ANALGESIA. THESE EFFECTS REQUIRED C/EPBBETA-MEDIATED TRANSCRIPTIONAL ACTIVATION OF EHMT2 (EUCHROMATIC HISTONE-LYSINE N-METHYLTRANSFERASE 2), WHICH ENCODES G9A, AN EPIGENETIC SILENCER OF THE GENES ENCODING KV1.2 AND MOR. BLOCKING THE INCREASE IN C/EBPBETA IN THE DRG IMPROVED MORPHINE ANALGESIA AFTER CCI. THESE RESULTS SUGGEST THAT C/EBPBETA IS AN ENDOGENOUS INITIATOR OF NEUROPATHIC PAIN AND COULD BE A POTENTIAL TARGET FOR THE PREVENTION AND TREATMENT OF THIS DISORDER. 2017 18 2826 27 FLUOXETINE EPIGENETICALLY ALTERS THE CAMKIIALPHA PROMOTER IN NUCLEUS ACCUMBENS TO REGULATE DELTAFOSB BINDING AND ANTIDEPRESSANT EFFECTS. CHRONIC SOCIAL DEFEAT STRESS IN MICE PRODUCES A SUSCEPTIBLE PHENOTYPE CHARACTERIZED BY SEVERAL BEHAVIORAL ABNORMALITIES CONSISTENT WITH HUMAN DEPRESSION THAT ARE REVERSED BY CHRONIC BUT NOT ACUTE EXPOSURE TO ANTIDEPRESSANT MEDICATIONS. RECENT WORK IN ADDICTION MODELS DEMONSTRATES THAT THE TRANSCRIPTION FACTOR DELTAFOSB AND PROTEIN KINASE CALMODULIN-DEPENDENT PROTEIN KINASE II (CAMKII) ARE CO-REGULATED IN NUCLEUS ACCUMBENS (NAC), A BRAIN REWARD REGION IMPLICATED IN BOTH ADDICTION AND DEPRESSION MODELS INCLUDING SOCIAL DEFEAT. PREVIOUS WORK HAS ALSO DEMONSTRATED THAT DELTAFOSB IS INDUCED IN NAC AFTER CHRONIC SOCIAL DEFEAT STRESS OR AFTER CHRONIC ANTIDEPRESSANT TREATMENT, WHEREIN IT MEDIATES A PRO-RESILIENCE OR ANTIDEPRESSANT-LIKE PHENOTYPE. HERE, USING CHROMATIN IMMUNOPRECIPITATION ASSAYS, WE FOUND THAT DELTAFOSB BINDS THE CAMKIIALPHA GENE PROMOTER IN NAC AND THAT THIS BINDING INCREASES AFTER MICE ARE EXPOSED TO CHRONIC SOCIAL DEFEAT STRESS. PARADOXICALLY, CHRONIC EXPOSURE TO THE ANTIDEPRESSANT FLUOXETINE REDUCES BINDING OF DELTAFOSB TO THE CAMKIIALPHA PROMOTER AND REDUCES CAMKII EXPRESSION IN NAC, DESPITE THE FACT THAT DELTAFOSB IS INDUCED UNDER THESE CONDITIONS. THESE DATA SUGGEST A NOVEL EPIGENETIC MECHANISM OF ANTIDEPRESSANT ACTION, WHEREBY FLUOXETINE INDUCES SOME CHROMATIN CHANGE AT THE CAMKIIALPHA PROMOTER, WHICH BLOCKS THE DELTAFOSB BINDING. INDEED, CHRONIC FLUOXETINE REDUCES ACETYLATION AND INCREASES LYSINE-9 DIMETHYLATION OF HISTONE H3 AT THE CAMKIIALPHA PROMOTER IN NAC, EFFECTS ALSO SEEN IN DEPRESSED HUMANS EXPOSED TO ANTIDEPRESSANTS. OVEREXPRESSION OF CAMKII IN NAC BLOCKS FLUOXETINE'S ANTIDEPRESSANT EFFECTS IN THE CHRONIC SOCIAL DEFEAT PARADIGM, WHEREAS INHIBITION OF CAMKII ACTIVITY IN NAC MIMICS FLUOXETINE EXPOSURE. THESE FINDINGS SUGGEST THAT EPIGENETIC SUPPRESSION OF CAMKIIALPHA EXPRESSION IN NAC IS BEHAVIORALLY RELEVANT AND OFFER A NOVEL PATHWAY FOR POSSIBLE THERAPEUTIC INTERVENTION IN DEPRESSION AND RELATED SYNDROMES. 2014 19 2012 21 EPIGENETIC BASIS OF OPIATE SUPPRESSION OF BDNF GENE EXPRESSION IN THE VENTRAL TEGMENTAL AREA. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS A CRUCIAL ROLE IN MODULATING NEURAL AND BEHAVIORAL PLASTICITY TO DRUGS OF ABUSE. WE FOUND A PERSISTENT DOWNREGULATION OF EXON-SPECIFIC BDNF EXPRESSION IN THE VENTRAL TEGMENTAL AREA (VTA) IN RESPONSE TO CHRONIC OPIATE EXPOSURE, WHICH WAS MEDIATED BY SPECIFIC EPIGENETIC MODIFICATIONS AT THE CORRESPONDING BDNF GENE PROMOTERS. EXPOSURE TO CHRONIC MORPHINE INCREASED STALLING OF RNA POLYMERASE II AT THESE BDNF PROMOTERS IN VTA AND ALTERED PERMISSIVE AND REPRESSIVE HISTONE MODIFICATIONS AND OCCUPANCY OF THEIR REGULATORY PROTEINS AT THE SPECIFIC PROMOTERS. FURTHERMORE, WE FOUND THAT MORPHINE SUPPRESSED BINDING OF PHOSPHO-CREB (CAMP RESPONSE ELEMENT BINDING PROTEIN) TO BDNF PROMOTERS IN VTA, WHICH RESULTED FROM ENRICHMENT OF TRIMETHYLATED H3K27 AT THE PROMOTERS, AND THAT DECREASED NURR1 (NUCLEAR RECEPTOR RELATED-1) EXPRESSION ALSO CONTRIBUTED TO BDNF REPRESSION AND ASSOCIATED BEHAVIORAL PLASTICITY TO MORPHINE. OUR FINDINGS SUGGEST PREVIOUSLY UNKNOWN EPIGENETIC MECHANISMS OF MORPHINE-INDUCED MOLECULAR AND BEHAVIORAL NEUROADAPTATIONS. 2015 20 6639 23 UNRAVELING THE EPIGENOMIC AND TRANSCRIPTOMIC INTERPLAY DURING ALCOHOL-INDUCED ANXIOLYSIS. POSITIVE EFFECTS OF ALCOHOL DRINKING SUCH AS ANXIOLYSIS AND EUPHORIA APPEAR TO BE A CRUCIAL FACTOR IN THE INITIATION AND MAINTENANCE OF ALCOHOL USE DISORDER (AUD). HOWEVER, THE MECHANISMS THAT LEAD FROM CHROMATIN REORGANIZATION TO TRANSCRIPTOMIC CHANGES AFTER ACUTE ETHANOL EXPOSURE REMAIN UNKNOWN. HERE, WE USED ASSAY FOR TRANSPOSASE-ACCESSIBLE CHROMATIN FOLLOWED BY HIGH THROUGHPUT SEQUENCING (ATAC-SEQ) AND RNA-SEQ TO INVESTIGATE EPIGENOMIC AND TRANSCRIPTOMIC CHANGES THAT UNDERLIE ANXIOLYTIC EFFECTS OF ACUTE ETHANOL USING AN ANIMAL MODEL. ANALYSIS OF ATAC-SEQ DATA REVEALED AN OVERALL OPEN OR PERMISSIVE CHROMATIN STATE THAT WAS ASSOCIATED WITH TRANSCRIPTOMIC CHANGES IN THE AMYGDALA AFTER ACUTE ETHANOL EXPOSURE. WE IDENTIFIED A CANDIDATE GENE, HIF3A (HYPOXIA-INDUCIBLE FACTOR 3, ALPHA SUBUNIT), THAT HAD 'OPEN' CHROMATIN REGIONS (ATAC-SEQ PEAKS), ASSOCIATED WITH SIGNIFICANTLY INCREASED ACTIVE EPIGENETIC HISTONE ACETYLATION MARKS AND DECREASED DNA METHYLATION AT THESE REGIONS. THE MRNA LEVELS OF HIF3A WERE INCREASED BY ACUTE ETHANOL EXPOSURE, BUT DECREASED IN THE AMYGDALA DURING WITHDRAWAL AFTER CHRONIC ETHANOL EXPOSURE. KNOCKDOWN OF HIF3A EXPRESSION IN THE CENTRAL NUCLEUS OF AMYGDALA ATTENUATED ACUTE ETHANOL-INDUCED INCREASES IN HIF3A MRNA LEVELS AND BLOCKED ANXIOLYSIS IN RATS. THESE DATA INDICATE THAT CHROMATIN ACCESSIBILITY AND TRANSCRIPTOMIC SIGNATURES IN THE AMYGDALA AFTER ACUTE ETHANOL EXPOSURE UNDERLIE ANXIOLYSIS AND POSSIBLY PRIME THE CHROMATIN FOR THE DEVELOPMENT OF AUD. 2022