1 6509 85 TRANSCRIPTION FACTOR RFX1 IS UBIQUITINATED BY E3 LIGASE STUB1 IN SYSTEMIC LUPUS ERYTHEMATOSUS. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC AUTOIMMUNE DISEASE CAUSED BY COMPLEX INTERACTIONS BETWEEN GENES AND THE ENVIRONMENT. THE EXPRESSION LEVEL OF TRANSCRIPTION FACTOR REGULATORY FACTOR X 1 (RFX1) IS REDUCED IN T CELLS FROM SLE PATIENTS. RFX1 CAN REGULATE EPIGENETIC MODIFICATIONS OF CD70 AND CD11A AND PLAYS AN IMPORTANT ROLE IN THE DEVELOPMENT OF SLE. HOWEVER, THE MECHANISMS THAT MEDIATE REDUCTION OF RFX1 IN SLE ARE UNCLEAR. HERE, WE DEMONSTRATE THAT RFX1 PROTEIN EXPRESSION CAN BE TIGHTLY REGULATED BY POLYUBIQUITINATION-MEDIATED PROTEOSOMAL DEGRADATION VIA STIP1 HOMOLOGY AND U-BOX CONTAINING PROTEIN 1 (STUB1). THE E3 LIGASE STUB1 IS UPREGULATED IN CD4(+)T CELLS OF SLE PATIENTS COMPARED TO HEALTHY SUBJECTS. OVEREXPRESSION OF STUB1 IN CD4(+)T CELLS LEADS TO UPREGULATION OF LEVELS OF CD70 AND CD11A IN T CELLS. THE MODULATION OF STUB1 ACTIVITY MAY PROVIDE A NOVEL THERAPEUTIC APPROACH FOR SLE. 2016 2 3945 41 LNCRNA IL21-AS1 INTERACTS WITH HNRNPU PROTEIN TO PROMOTE IL21 OVEREXPRESSION AND ABERRANT DIFFERENTIATION OF TFH CELLS IN SYSTEMIC LUPUS ERYTHEMATOSUS. BACKGROUND: THE ABERRANT DIFFERENTIATION OF T FOLLICULAR HELPER (TFH) CELLS PLAYS AN IMPORTANT ROLE IN THE PATHOGENESIS OF SYSTEMIC LUPUS ERYTHEMATOSUS (SLE). HOWEVER, THE MECHANISM OF REGULATING TFH CELLS DIFFERENTIATION REMAINS UNCLEAR. LONG NONCODING RNAS (LNCRNAS) ACT AS IMPORTANT REGULATORS IN THE PROCESSES OF INNATE AND ADAPTIVE IMMUNE RESPONSE. WHETHER LNCRNAS ARE INVOLVED IN REGULATING TFH CELL DIFFERENTIATION AND AUTOIMMUNE RESPONSES NEED TO BE FURTHER IDENTIFIED. METHODS: THE CHARACTERS AND FUNCTIONS OF HUMAN IL21-AS1 AND ITS MOUSE HOMOLOGOUS LNCRNA (MIL21-AS) WERE INVESTIGATED BY A SERIES OF BIOCHEMICAL ASSAYS AND CELL TRANSFECTION ASSAY. MIL21-AS1 REGULATING HUMORAL IMMUNE RESPONSE IN VIVO WAS EXPLORED BY KEYHOLE LIMPET HAEMOCYANIN (KLH) AND CHRONIC GRAFT VERSUS HOST DISEASE (CGVHD) MODEL. RESULTS: HUMAN IL21-AS1 AND ITS MOUSE HOMOLOGOUS LNCRNA (MIL21-AS) WERE IDENTIFIED AND CLONED. WE UNCOVERED THAT IL21-AS1 WAS HIGHLY EXPRESSED IN CD4(+) T CELLS OF SLE PATIENTS AND TFH CELLS, WHICH PROMOTED DIFFERENTIATION OF TFH CELLS. MECHANISTICALLY, IL21-AS1 BOUND HETEROGENEOUS NUCLEAR RIBONUCLEOPROTEIN U AND RECRUITED ACETYLTRANSFERASES CREB-BINDING PROTEIN TO THE PROMOTER OF IL21, LEADING TO THE TRANSCRIPTIONAL ACTIVATION OF IL21 AND TFH CELLS DIFFERENTIATION THROUGH INCREASING HISTONE H3 ACETYLATION LEVEL ON IL21 PROMOTER. MOREOVER, TFH PROPORTION AND ANTIBODIES PRODUCTION WERE SIGNIFICANTLY INCREASED IN MIL21-AS KNOCK-IN MICE IMMUNIZED WITH KLH. MIL21-AS1 OVEREXPRESSION ALSO EXACERBATED THE LUPUS-LIKE PHENOTYPE IN CGVHD MICE MODEL. CONCLUSIONS: OUR RESULTS DEMONSTRATE THAT IL21-AS1 ACTIVATES IL21 TRANSCRIPTION VIA EPIGENETIC MECHANISM TO PROMOTE GERMINAL CENTRE RESPONSE, ADDING INSIGHT INTO THE MOLECULAR REGULATION OF AUTOIMMUNE PATHOGENESIS AND PROVIDING A NOVEL TARGET FOR SLE TREATMENT. 2022 3 35 28 A CHROMATIN ACTIVITY-BASED CHEMOPROTEOMIC APPROACH REVEALS A TRANSCRIPTIONAL REPRESSOME FOR GENE-SPECIFIC SILENCING. IMMUNE CELLS DEVELOP ENDOTOXIN TOLERANCE (ET) AFTER PROLONGED STIMULATION. ET INCREASES THE LEVEL OF A REPRESSION MARK H3K9ME2 IN THE TRANSCRIPTIONALLY SILENT CHROMATIN SPECIFICALLY ASSOCIATED WITH PRO-INFLAMMATORY GENES. HOWEVER, IT IS NOT CLEAR WHAT PROTEINS ARE FUNCTIONALLY INVOLVED IN THIS PROCESS. HERE WE SHOW THAT A NOVEL CHROMATIN ACTIVITY-BASED CHEMOPROTEOMIC (CHAC) APPROACH CAN DISSECT THE FUNCTIONAL CHROMATIN PROTEIN COMPLEXES THAT REGULATE ET-ASSOCIATED INFLAMMATION. USING UNC0638 THAT BINDS THE ENZYMATICALLY ACTIVE H3K9-SPECIFIC METHYLTRANSFERASE G9A/GLP, CHAC REVEALS THAT G9A IS CONSTITUTIVELY ACTIVE AT A G9A-DEPENDENT MEGA-DALTON REPRESSOME IN PRIMARY ENDOTOXIN-TOLERANT MACROPHAGES. G9A/GLP BROADLY IMPACTS THE ET-SPECIFIC REPROGRAMMING OF THE HISTONE CODE LANDSCAPE, CHROMATIN REMODELLING AND THE ACTIVITIES OF SELECT TRANSCRIPTION FACTORS. WE DISCOVER THAT THE G9A-DEPENDENT EPIGENETIC ENVIRONMENT PROMOTES THE TRANSCRIPTIONAL REPRESSION ACTIVITY OF C-MYC FOR GENE-SPECIFIC CO-REGULATION OF CHRONIC INFLAMMATION. CHAC MAY ALSO BE APPLICABLE TO DISSECT OTHER FUNCTIONAL PROTEIN COMPLEXES IN THE CONTEXT OF PHENOTYPIC CHROMATIN ARCHITECTURES. 2014 4 5863 23 SUPPRESSION OF ALLERGIC ASTHMA BY LOSS OF FUNCTION OF MIZ1-MEDIATED TH1 SKEWING. ASTHMA IS THE MOST PREVALENT CHRONIC RESPIRATORY DISEASE WORLDWIDE. THERE IS CURRENTLY NO CURE, AND IT REMAINS AN IMPORTANT CAUSE OF MORBIDITY AND MORTALITY. HERE WE REPORT THAT LUNG-SPECIFIC LOSS OF FUNCTION OF THE TRANSCRIPTION FACTOR MIZ1 (C-MYC-INTERACTING ZINC FINGER PROTEIN-1) UPREGULATES THE PRO-T-HELPER CELL TYPE 1 CYTOKINE IL-12. UPREGULATION OF IL-12 IN TURN STIMULATES A TH1 RESPONSE, THEREBY COUNTERACTING T-HELPER CELL TYPE 2 RESPONSE AND PREVENTING THE ALLERGIC RESPONSE IN MOUSE MODELS OF HOUSE DUST MITE- AND OVA (OVALBUMIN)-INDUCED ASTHMA. USING TRANSGENIC MICE EXPRESSING CRE UNDER A CELL-SPECIFIC PROMOTER, WE DEMONSTRATE THAT MIZ1 ACTS IN LUNG EPITHELIAL CELLS AND DENDRITIC CELLS IN ASTHMA. CHROMATIN IMMUNOPRECIPITATION COUPLED WITH HIGH-THROUGHPUT DNA SEQUENCING OR QUANTITATIVE PCR REVEALS THE BINDING OF MIZ1 ON THE IL12 PROMOTER INDICATING DIRECT REPRESSION OF IL-12 BY MIZ1. IN ADDITION, HDAC1 (HISTONE DEACETYLASE 1) IS RECRUITED TO THE IL12 PROMOTER IN A MIZ1-DEPDENENT MANNER, SUGGESTING EPIGENETIC REPRESSION OF IL12 BY MIZ1. FURTHERMORE, MIZ1 IS UPREGULATED IN THE LUNGS OF ASTHMATIC MICE. OUR DATA TOGETHER SUGGEST THAT MIZ1 IS UPREGULATED DURING ASTHMA, WHICH IN TURN PROMOTES ASTHMA PATHOGENESIS BY PREVENTING TH1 SKEWING THROUGH THE TRANSCRIPTIONAL REPRESSION OF IL-12. 2022 5 5601 25 RORALPHA IS CRUCIAL FOR ATTENUATED INFLAMMATORY RESPONSE TO MAINTAIN INTESTINAL HOMEOSTASIS. RETINOIC ACID-RELATED ORPHAN RECEPTOR ALPHA (RORALPHA) FUNCTIONS AS A TRANSCRIPTION FACTOR FOR VARIOUS BIOLOGICAL PROCESSES, INCLUDING CIRCADIAN RHYTHM, CANCER, AND METABOLISM. HERE, WE GENERATE INTESTINAL EPITHELIAL CELL (IEC)-SPECIFIC RORALPHA-DEFICIENT (RORALPHA(DELTAIEC)) MICE AND FIND THAT RORALPHA IS CRUCIAL FOR MAINTAINING INTESTINAL HOMEOSTASIS BY ATTENUATING NUCLEAR FACTOR KAPPAB (NF-KAPPAB) TRANSCRIPTIONAL ACTIVITY. RORALPHA(DELTAIEC) MICE EXHIBIT EXCESSIVE INTESTINAL INFLAMMATION AND HIGHLY ACTIVATED INFLAMMATORY RESPONSES IN THE DEXTRAN SULFATE SODIUM (DSS) MOUSE COLITIS MODEL. TRANSCRIPTOME ANALYSIS REVEALS THAT DELETION OF RORALPHA LEADS TO UP-REGULATION OF NF-KAPPAB TARGET GENES IN IECS. CHROMATIN IMMUNOPRECIPITATION ANALYSIS REVEALS CORECRUITMENT OF RORALPHA AND HISTONE DEACETYLASE 3 (HDAC3) ON NF-KAPPAB TARGET PROMOTERS AND SUBSEQUENT DISMISSAL OF CREB BINDING PROTEIN (CBP) AND BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) FOR TRANSCRIPTIONAL REPRESSION. TOGETHER, WE DEMONSTRATE THAT RORALPHA/HDAC3-MEDIATED ATTENUATION OF NF-KAPPAB SIGNALING CONTROLS THE BALANCE OF INFLAMMATORY RESPONSES, AND THERAPEUTIC STRATEGIES TARGETING THIS EPIGENETIC REGULATION COULD BE BENEFICIAL TO THE TREATMENT OF CHRONIC INFLAMMATORY DISEASES, INCLUDING INFLAMMATORY BOWEL DISEASE (IBD). 2019 6 5153 27 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 7 460 27 ARACHIDONIC ACID 15-LIPOXYGENASE: EFFECTS OF ITS EXPRESSION, METABOLITES, AND GENETIC AND EPIGENETIC VARIATIONS ON AIRWAY INFLAMMATION. ARACHIDONIC ACID 15-LIPOXYGENASE (ALOX15) IS AN ENZYME THAT CAN OXIDIZE POLYUNSATURATED FATTY ACIDS. ALOX15 IS STRONGLY EXPRESSED IN AIRWAY EPITHELIAL CELLS, WHERE IT CATALYZES THE CONVERSION OF ARACHIDONIC ACID TO 15-HYDROXYEICOSATETRAENOIC ACID (15-HETE) INVOLVED IN VARIOUS AIRWAY INFLAMMATORY DISEASES. INTERLEUKIN (IL)-4 AND IL-13 INDUCE ALOX15 EXPRESSION BY ACTIVATING JAK2 AND TYK2 KINASES AS WELL AS SIGNAL TRANSDUCERS AND ACTIVATORS OF TRANSCRIPTION (STATS) 1/3/5/6. ALOX15 UP-REGULATION AND SUBSEQUENT ASSOCIATION WITH PHOSPHATIDYLETHANOLAMINE-BINDING PROTEIN 1 (PEBP1) ACTIVATE THE MITOGEN-ACTIVATED EXTRACELLULAR SIGNAL-REGULATED KINASE (MEK)-EXTRACELLULAR SIGNAL-REGULATED KINASE (ERK) PATHWAY, THUS INDUCING EOSINOPHIL-MEDIATED AIRWAY INFLAMMATION. IN ADDITION, ALOX15 PLAYS A SIGNIFICANT ROLE IN PROMOTING THE MIGRATION OF IMMUNE CELLS, SUCH AS IMMATURE DENDRITIC CELLS, ACTIVATED T CELLS, AND MAST CELLS, AND AIRWAY REMODELING, INCLUDING GOBLET CELL DIFFERENTIATION. GENOME-WIDE ASSOCIATION STUDIES HAVE REVEALED MULTIPLE ALOX15 VARIANTS AND THEIR SIGNIFICANT CORRELATION WITH THE RISK OF DEVELOPING AIRWAY DISEASES. THE EPIGENETIC MODIFICATIONS OF THE ALOX15 GENE, SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS, HAVE BEEN SHOWN TO CLOSELY RELATE WITH AIRWAY INFLAMMATION. THIS REVIEW SUMMARIZES THE ROLE OF ALOX15 IN DIFFERENT PHENOTYPES OF ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, CHRONIC RHINOSINUSITIS, ASPIRIN-EXACERBATED RESPIRATORY DISEASE, AND NASAL POLYPS, SUGGESTING NEW TREATMENT STRATEGIES FOR THESE AIRWAY INFLAMMATORY DISEASES WITH COMPLEX ETIOLOGY AND POOR TREATMENT RESPONSE. 2021 8 6657 33 UPREGULATED KAT7 IN SYNOVIAL FIBROBLASTS PROMOTES TH17 CELL DIFFERENTIATION AND INFILTRATION IN RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC AUTOIMMUNE DISEASE INVOLVING MULTIPLE CELLULAR PARTICIPANTS, OF WHICH SYNOVIAL FIBROBLASTS (SFS) ARE TIGHTLY CONNECTED WITH THE DEVELOPMENT AND PROGRESSION OF RA. HERE, WE PROVIDE EVIDENCE CONFIRMING THAT KAT7, AN H4-SPECIFIC HISTONE ACETYLASE, IS UPREGULATED IN SFS OF RA PATIENTS, WHICH IS AT LEAST ATTRIBUTED TO THE STIMULATION BY RA-ASSOCIATED PROINFLAMMATORY CYTOKINES, SUCH AS TNF-ALPHA, IL-1BETA OR IFN-GAMMA. IN ADDITION, KAT7 OVEREXPRESSION IN CULTURED HUMAN FIBROBLAST-LIKE SYNOVIOCYTES (HFLSS) INDUCES IL-6 AND TGF-BETA EXPRESSION THROUGH AN EPIGENETIC MECHANISM, AND IN VITRO T HELPER 17 (TH17) CELL POLARIZATION CULTURED IN THESE SUPERNATANTS SHOWS PROMOTED CELL DIFFERENTIATION. MOREOVER, KAT7 OVEREXPRESSION IN HFLSS INDUCES CCL20 EXPRESSION VIA P44/42 MAPK PATHWAY, WHEREBY PROMOTING TH17 CELL MIGRATION. THESE TWO ACTIVITIES OF KAT7 IN RA SFS INDICATE ITS POTENTIAL ROLES IN ACCELERATING RA PATHOLOGY. OVERALL, THESE RESULTS DEMONSTRATE SOME CONNECTIONS BETWEEN KAT7 UPREGULATED IN RA SFS AND RA PROGRESSION AND PRESENT THE INHIBITION OF KAT7 ACTIVITY AS A NOVEL THERAPEUTIC TARGET FOR INTERFERING RA DISEASE. 2017 9 2080 26 EPIGENETIC DNA METHYLATION OF EBI3 MODULATES HUMAN INTERLEUKIN-35 FORMATION VIA NFKB SIGNALING: A PROMISING THERAPEUTIC OPTION IN ULCERATIVE COLITIS. ULCERATIVE COLITIS (UC), A SEVERE CHRONIC DISEASE WITH UNCLEAR ETIOLOGY THAT IS ASSOCIATED WITH INCREASED RISK FOR COLORECTAL CANCER, IS ACCOMPANIED BY DYSREGULATION OF CYTOKINES. EPSTEIN-BARR VIRUS-INDUCED GENE 3 (EBI3) ENCODES A SUBUNIT IN THE UNIQUE HETERODIMERIC IL-12 CYTOKINE FAMILY OF EITHER PRO- OR ANTI-INFLAMMATORY FUNCTION. AFTER HAVING RECENTLY DEMONSTRATED THAT UPREGULATION OF EBI3 BY HISTONE ACETYLATION ALLEVIATES DISEASE SYMPTOMS IN A DEXTRAN SULFATE SODIUM (DSS)-TREATED MOUSE MODEL OF CHRONIC COLITIS, WE NOW AIMED TO EXAMINE A POSSIBLE FURTHER EPIGENETIC REGULATION OF EBI3 BY DNA METHYLATION UNDER INFLAMMATORY CONDITIONS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR (DNMTI) DECITABINE (DAC) AND TNFALPHA LED TO SYNERGISTIC UPREGULATION OF EBI3 IN HUMAN COLON EPITHELIAL CELLS (HCEC). USE OF DIFFERENT SIGNALING PATHWAY INHIBITORS INDICATED NFKAPPAB SIGNALING WAS NECESSARY AND PROPORTIONAL TO THE SYNERGISTIC EBI3 INDUCTION. MALDI-TOF/MS AND HPLC-ESI-MS/MS ANALYSIS OF DAC/TNFALPHA-TREATED HCEC IDENTIFIED IL-12P35 AS THE MOST PROBABLE BINDING PARTNER TO FORM A FUNCTIONAL PROTEIN. EBI3/IL-12P35 HETERODIMERS (IL-35) INDUCE THEIR OWN GENE UPREGULATION, SOMETHING THAT WAS INDEED OBSERVED IN HCEC CULTURED WITH MEDIA FROM PREVIOUSLY DAC/TNFALPHA-TREATED HCEC. THESE RESULTS SUGGEST THAT UNDER INFLAMMATORY AND DEMETHYLATING CONDITIONS THE UPREGULATION OF EBI3 RESULTS IN THE FORMATION OF ANTI-INFLAMMATORY IL-35, WHICH MIGHT BE CONSIDERED AS A THERAPEUTIC TARGET IN COLITIS. 2021 10 3386 29 HOMEOSTATIC TISSUE RESPONSES IN SKIN BIOPSIES FROM NOMID PATIENTS WITH CONSTITUTIVE OVERPRODUCTION OF IL-1BETA. THE AUTOINFLAMMATORY DISORDER, NEONATAL-ONSET MULTISYSTEM INFLAMMATORY DISEASE (NOMID) IS THE MOST SEVERE PHENOTYPE OF DISORDERS CAUSED BY MUTATIONS IN CIAS1 THAT RESULT IN INCREASED PRODUCTION AND SECRETION OF ACTIVE IL-1BETA. NOMID PATIENTS PRESENT WITH SYSTEMIC AND ORGAN-SPECIFIC INFLAMMATION OF THE SKIN, CENTRAL NERVOUS SYSTEM AND BONE, AND RESPOND DRAMATICALLY TO TREATMENT WITH IL-1 BLOCKING AGENTS. WE COMPARED THE CELLULAR INFILTRATES AND TRANSCRIPTOME OF SKIN BIOPSIES FROM PATIENTS WITH NOMID (N = 14) BEFORE TREATMENT (LESIONAL (LS) AND NON-LESIONAL (PRE-NL) SKIN) AND AFTER TREATMENT (POST-NL) WITH THE IL-1 BLOCKER ANAKINRA (RECOMBINANT IL-1 RECEPTOR ANTAGONIST, KINERET(R), SWEDISH ORPHAN BIOVITRUM AB, SOBI), TO NORMAL SKIN (N = 5) TO ASSESS TISSUE RESPONSES IN THE CONTEXT OF UNTREATED AND TREATED DISEASE. ABUNDANT NEUTROPHILS DISTINGUISH LS SKIN FROM PRE-NL AND POST-NL SKIN. CD11C(+) DERMAL DENDRITIC CELLS AND CD163(+) MACROPHAGES EXPRESSED ACTIVATED CASPASE-1 AND ARE A LIKELY SOURCE OF CUTANEOUS IL-1 PRODUCTION. TREATMENT WITH ANAKINRA LED TO THE DISAPPEARANCE OF NEUTROPHILS, BUT CD3(+) T CELLS AND HLA-DR(+) CELLS REMAINED ELEVATED. AMONG THE UPREGULATED GENES IL-6, IL-8, TNF, IL-17A, CCL20, AND THE NEUTROPHIL DEFENSINS DEFA1 AND DEFA3 WERE DIFFERENTIALLY REGULATED IN LS TISSUES (COMPARED TO NORMAL SKIN). IMPORTANT SIGNIFICANTLY DOWNREGULATED PATHWAYS IN LS SKIN INCLUDED IL-1R/TLR SIGNALING, TYPE I AND II CYTOKINE RECEPTOR SIGNALING, MITOCHONDRIAL DYSFUNCTION, AND ANTIGEN PRESENTATION. THE DIFFERENTIAL EXPRESSION AND REGULATION OF MICRORNAS AND PATHWAYS INVOLVED IN POST-TRANSCRIPTIONAL MODIFICATION WERE SUGGESTIVE OF EPIGENETIC MODIFICATION IN THE CHRONICALLY INFLAMED TISSUE. OVERALL, THE DYSREGULATED GENES AND PATHWAYS SUGGEST EXTENSIVE "ADAPTIVE" MECHANISMS TO CONTROL INFLAMMATION AND MAINTAIN TISSUE HOMEOSTASIS, LIKELY TRIGGERED BY CHRONIC IL-1 RELEASE IN THE SKIN OF PATIENTS WITH NOMID. 2012 11 768 24 CD47 (CLUSTER OF DIFFERENTIATION 47). CD47, ALSO KNOWN AS INTEGRIN-ASSOCIATED PROTEIN, IS A CONSTITUTIVELY AND UBIQUITOUSLY EXPRESSED TRANSMEMBRANE RECEPTOR. CD47 IS CONSERVED ACROSS AMNIOTES INCLUDING MAMMALS, REPTILES, AND BIRDS. EXPRESSION IS INCREASED IN MANY CANCERS AND, IN NON-MALIGNANT CELLS, BY STRESS AND WITH AGING. THE UP-REGULATION OF CD47 EXPRESSION IS GENERALLY EPIGENETIC, WHEREAS GENE AMPLIFICATION OCCURS WITH LOW FREQUENCY IN SOME CANCERS. CD47 IS A HIGH AFFINITY SIGNALING RECEPTOR FOR THE SECRETED PROTEIN THROMBOSPONDIN-1 (THBS1) AND THE COUNTER-RECEPTOR FOR SIGNAL REGULATORY PROTEIN-ALPHA (SIRPA, SIRPALPHA) AND SIRPGAMMA (SIRPG). CD47 INTERACTION WITH SIRPALPHA SERVES AS A MARKER OF SELF TO INNATE IMMUNE CELLS AND THEREBY PROTECTS CANCER CELLS FROM PHAGOCYTIC CLEARANCE. CONSEQUENTLY, HIGHER CD47 CORRELATES WITH A POOR PROGNOSIS IN SOME CANCERS, AND THERAPEUTIC BLOCKADE CAN SUPPRESS TUMOR GROWTH BY ENHANCING INNATE ANTITUMOR IMMUNITY. CD47 EXPRESSED ON CYTOTOXIC T CELLS, DENDRITIC CELLS, AND NK CELLS MEDIATES INHIBITORY THBS1 SIGNALING THAT FURTHER LIMITS ANTITUMOR IMMUNITY. CD47 LATERALLY ASSOCIATES WITH SEVERAL INTEGRINS AND THEREBY REGULATES CELL ADHESION AND MIGRATION. CD47 HAS ADDITIONAL LATERAL BINDING PARTNERS IN SPECIFIC CELL TYPES, AND LIGATION OF CD47 IN SOME CASES MODULATES THEIR FUNCTION. THBS1-CD47 SIGNALING IN NON-MALIGNANT CELLS INHIBITS NITRIC OXIDE/CGMP, CALCIUM, AND VEGF SIGNALING, MITOCHONDRIAL HOMEOSTASIS, STEM CELL MAINTENANCE, PROTECTIVE AUTOPHAGY, AND DNA DAMAGE RESPONSE, AND PROMOTES NADPH OXIDASE ACTIVITY. CD47 SIGNALING IS A PHYSIOLOGICAL REGULATOR OF PLATELET ACTIVATION, ANGIOGENESIS AND BLOOD FLOW. THBS1/CD47 SIGNALING IS FREQUENTLY DYSREGULATED IN CHRONIC DISEASES. 2021 12 3161 27 GRAINYHEAD-LIKE 2 (GRHL2) INHIBITS KERATINOCYTE DIFFERENTIATION THROUGH EPIGENETIC MECHANISM. WE RECENTLY IDENTIFIED GRAINYHEAD-LIKE 2 (GRHL2), A MAMMALIAN HOMOLOG OF GRAINYHEAD IN DROSOPHILA, TO BE A NOVEL TRANSCRIPTION FACTOR THAT REGULATES HTERT GENE EXPRESSION AND ENHANCES PROLIFERATION OF NORMAL HUMAN EPIDERMAL KERATINOCYTES (NHEK). IN THE CURRENT STUDY, WE SHOW THAT GRHL2 IMPAIRS KERATINOCYTE DIFFERENTIATION THROUGH TRANSCRIPTIONAL INHIBITION OF THE GENES CLUSTERED AT THE EPIDERMAL DIFFERENTIATION COMPLEX (EDC), LOCATED AT CHROMOSOME 1Q21. GENE EXPRESSION PROFILING AND SUBSEQUENT IN VITRO ASSAYS REVEALED CONSISTENT DOWNREGULATION OF EDC GENES, FOR EXAMPLE, IVL, KRT1, FLG, LCES, AND SPRRS, IN NHEK EXPRESSING EXOGENOUS GRHL2. IN VIVO BINDING ASSAY BY CHROMATIN IMMUNOPRECIPITATION REVEALED GRHL2 ASSOCIATION AT THE PROMOTER REGIONS OF ITS TARGET GENES, MANY OF WHICH BELONG TO EDC. EXOGENOUS GRHL2 EXPRESSION ALSO INHIBITED RECRUITMENT OF HISTONE DEMETHYLASE JMJD3 TO THE EDC GENE PROMOTERS AND ENHANCED THE LEVEL OF HISTONE 3 LYS 27 TRIMETHYLATION ENRICHMENT AT THESE PROMOTERS. SURVEY OF GRHL2 EXPRESSION IN HUMAN SKIN TISSUES DEMONSTRATED ENHANCED PROTEIN AND MRNA LEVELS IN CHRONIC SKIN LESIONS WITH IMPAIRED KERATINOCYTE DIFFERENTIATION, FOR EXAMPLE, ATOPIC DERMATITIS AND PSORIASIS, COMPARED WITH NORMAL EPIDERMIS. THESE DATA INDICATE THAT GRHL2 IMPAIRS EPIDERMAL DIFFERENTIATION BY INHIBITING EDC GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS AND SUPPORT ITS ROLE IN THE HYPERPROLIFERATIVE SKIN DISEASES. 2012 13 368 30 AMYLOID BETA-MEDIATED EPIGENETIC ALTERATION OF INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 CONTROLS CELL SURVIVAL IN ALZHEIMER'S DISEASE. SWEDISH DOUBLE MUTATION (KM670/671NL) OF AMYLOID PRECURSOR PROTEIN (APP) IS REPORTED TO INCREASE TOXIC AMYLOID BETA (ABETA) PRODUCTION VIA ABERRANT CLEAVAGE AT THE BETA-SECRETASE SITE AND THEREBY CAUSE EARLY-ONSET ALZHEIMER'S DISEASE (AD). HOWEVER, THE UNDERLYING MOLECULAR MECHANISMS LEADING TO AD PATHOGENESIS REMAINS LARGELY UNKNOWN. PREVIOUSLY, OUR TRANSCRIPTOME SEQUENCE ANALYSES REVEALED GLOBAL EXPRESSIONAL MODIFICATIONS OF OVER 600 GENES IN APP-SWEDISH MUTANT-EXPRESSING H4 (H4-SW) CELLS COMPARED TO WILD TYPE H4 CELLS. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 (IGFBP3) IS ONE GENE THAT SHOWED SIGNIFICANTLY DECREASED MRNA EXPRESSION IN H4-SW CELLS. IN THIS STUDY, WE INVESTIGATED THE FUNCTIONAL ROLE OF IGFBP3 IN AD PATHOGENESIS AND ELUCIDATED THE MECHANISMS REGULATING ITS EXPRESSION. WE OBSERVED DECREASED IGFBP3 EXPRESSION IN THE H4-SW CELL LINE AS WELL AS THE HIPPOCAMPUS OF AD MODEL TRANSGENIC MICE. TREATMENT WITH EXOGENOUS IGFBP3 PROTEIN INHIBITED ABETA1-42- INDUCED CELL DEATH AND CASPASE-3 ACTIVITY, WHEREAS SIRNA-MEDIATED SUPPRESSION OF IGFBP3 EXPRESSION INDUCED CELL DEATH AND CASPASE-3 CLEAVAGE. IN PRIMARY HIPPOCAMPAL NEURONS, ADMINISTRATION OF IGFBP3 PROTEIN BLOCKED APOPTOTIC CELL DEATH DUE TO ABETA1-42 TOXICITY. THESE DATA IMPLICATE A PROTECTIVE ROLE FOR IGFBP3 AGAINST ABETA1-42-MEDIATED APOPTOSIS. NEXT, WE INVESTIGATED THE REGULATORY MECHANISMS OF IGFBP3 EXPRESSION IN AD PATHOGENESIS. WE OBSERVED ABNORMAL IGFBP3 HYPERMETHYLATION WITHIN THE PROMOTER CPG ISLAND IN H4-SW CELLS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR 5-AZA-2'-DEOXYCYTIDINE RESTORED IGFBP3 EXPRESSION AT BOTH THE MRNA AND PROTEIN LEVELS. CHRONIC EXPOSURE TO ABETA1-42 INDUCED IGFBP3 HYPERMETHYLATION AT CPGS, PARTICULARLY AT LOCI -164 AND -173, AND SUBSEQUENTLY SUPPRESSED IGFBP3 EXPRESSION. THEREFORE, WE DEMONSTRATE THAT EXPRESSION OF ANTI-APOPTOTIC IGFBP3 IS REGULATED BY EPIGENETIC DNA METHYLATION, SUGGESTING A MECHANISM THAT CONTRIBUTES TO AD PATHOGENESIS. 2014 14 1293 27 DECREASED ERK AND JNK SIGNALING CONTRIBUTE TO GENE OVEREXPRESSION IN "SENESCENT" CD4+CD28- T CELLS THROUGH EPIGENETIC MECHANISMS. AN INFLAMMATORY AND CYTOTOXIC CD4+CD28- T CELL SUBSET INFILTRATES ATHEROSCLEROTIC PLAQUES AND IS IMPLICATED IN PLAQUE RUPTURE AND MYOCARDIAL INFARCTIONS. THIS PATHOLOGIC SUBSET DEVELOPS WITH REPLICATIVE STRESS AND IS FOUND IN PATIENTS WITH CHRONIC INFLAMMATORY DISEASES SUCH AS RA AS WELL AS WITH AGING. CD4+CD28- CELLS OVEREXPRESS GENES NORMALLY SUPPRESSED BY DNA METHYLATION IN CD4+CD28+ T CELLS, SUCH AS KIR, PERFORIN, AND CD70. HOW THIS SUBSET OVER EXPRESSES METHYLATION-SENSITIVE GENES IS UNKNOWN. DNA METHYLATION PATTERNS ARE MAINTAINED IN PROLIFERATING CELLS BY DNMTS, WHICH ARE UP-REGULATED DURING MITOSIS BY THE ERK AND JNK SIGNALING PATHWAYS. WE HYPOTHESIZED THAT DEFECTS IN THESE SIGNALING PATHWAYS CONTRIBUTE TO ALTERED GENE EXPRESSION IN HUMAN CD4+CD28- CELLS THROUGH EFFECTS ON DNA METHYLATION. WE REPORT THAT SIGNALING THROUGH THE ERK AND JNK PATHWAYS IS DECREASED IN CD4+CD28- RELATIVE TO CD4+CD28+ CELLS FROM THE SAME INDIVIDUALS AND THAT ERK AND JNK PATHWAY INHIBITION DECREASES DNMT1 AND -3A LEVELS, WHICH IN TURN, CAUSES DEMETHYLATION AND OVEREXPRESSION OF THE TNFSF7 (CD70) GENE. WE ALSO REPORT THAT CD4+CD28- T CELLS OVEREXPRESS PP5, A STRESS-INDUCED INHIBITOR OF THE ERK AND JNK SIGNALING PATHWAYS THAT MAY CONTRIBUTE TO THE SIGNALING DEFECTS. WE CONCLUDE THAT DECREASED ERK AND JNK SIGNALING IN THE CD4+CD28- SUBSET, ARISING WITH REPLICATIVE STRESS, CAN LEAD TO THE OVEREXPRESSION OF NORMALLY SUPPRESSED GENES THROUGH EFFECTS ON DNMTS AND CONSEQUENTLY, CHROMATIN STRUCTURE. 2010 15 1668 29 DOWNREGULATION OF SOCS1 INCREASES INTERFERON-INDUCED ISGYLATION DURING DIFFERENTIATION OF INDUCED-PLURIPOTENT STEM CELLS TO HEPATOCYTES. BACKGROUND & AIMS: INCREASED EXPRESSION OF IFN-STIMULATED GENE 15 (ISG15) AND SUBSEQUENTLY INCREASED ISGYLATION ARE KEY FACTORS IN THE HOST RESPONSE TO VIRAL INFECTION. IN THIS STUDY, WE SOUGHT TO CHARACTERIZE THE EXPRESSION OF ISG15, ISGYLATION, AND ASSOCIATED ENZYMES AT EACH STAGE OF DIFFERENTIATION FROM INDUCED PLURIPOTENT STEM CELLS (IPSCS) TO HEPATOCYTES. METHODS: TO STUDY THE REGULATION OF ISGYLATION, WE UTILIZED PATIENT SAMPLES AND IN VITRO CELL CULTURE MODELS INCLUDING IPSCS, HEPATOCYTES-LIKE CELLS, IMMORTALIZED CELL LINES, AND PRIMARY HUMAN HEPATOCYTES. PROTEIN/MRNA EXPRESSION WERE MEASURED FOLLOWING TREATMENT WITH POLY(I:C), IFNALPHA AND HCV INFECTION. RESULTS: WHEN COMPARED TO HLCS, WE OBSERVED SEVERAL NOVEL ASPECTS OF THE ISGYLATION PATHWAY IN IPSCS. THESE INCLUDE A LOWER BASELINE EXPRESSION OF THE ISGYLATION-ACTIVATING ENZYME, UBE1L, A LACK OF IFN-INDUCED EXPRESSION OF THE ISGYLATION-CONJUGATION ENZYME UBE2L6, AN ATTENUATED ACTIVATION OF THE TRANSCRIPTION FACTOR STAT1 AND CONSTITUTIVE EXPRESSION OF SOCS1. ISGYLATION WAS OBSERVED IN IPSCS FOLLOWING DOWNREGULATION OF SOCS1, WHICH FACILITATED STAT1 ACTIVATION AND SUBSEQUENTLY INCREASED EXPRESSION OF UBE2L6. INTRIGUINGLY, HCV PERMISSIVE TRANSFORMED HEPATOMA CELL LINES DEMONSTRATED HIGHER INTRINSIC EXPRESSION OF SOCS1 AND WEAKER ISGYLATION FOLLOWING IFN TREATMENT. SOCS1 DOWNREGULATION IN HCV-INFECTED HUH 7.5.1 CELLS LED TO INCREASED ISGYLATION. CONCLUSIONS: HEREIN, WE SHOW THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. FURTHERMORE, AS IPSCS DIFFERENTIATE INTO HEPATOCYTES, EPIGENETIC MECHANISMS REGULATE ISGYLATION BY MODIFYING UBE1L AND SOCS1 EXPRESSION LEVELS. OVERALL, THIS STUDY DEMONSTRATES THAT THE DEVELOPMENT OF CELL-INTRINSIC INNATE IMMUNITY DURING THE DIFFERENTIATION OF IPSCS TO HEPATOCYTES PROVIDES INSIGHT INTO CELL TYPE-SPECIFIC REGULATION OF HOST DEFENSE RESPONSES AND RELATED ONCOGENIC PROCESSES. IMPACT AND IMPLICATIONS: TO ELUCIDATE THE MECHANISM UNDERLYING REGULATION OF ISGYLATION, A KEY PROCESS IN THE INNATE IMMUNE RESPONSE, WE STUDIED CHANGES IN ISGYLATION-ASSOCIATED GENES AT THE DIFFERENT STAGES OF DIFFERENTIATION FROM IPSCS TO HEPATOCYTES. WE FOUND THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. IMPORTANTLY, EPIGENETIC REGULATION OF SOCS1 AND SUBSEQUENTLY ISGYLATION MAY BE IMPORTANT FACTORS IN THE DEVELOPMENT OF CELL TYPE-SPECIFIC HOST DEFENSE RESPONSES IN HEPATOCYTES THAT SHOULD BE CONSIDERED WHEN STUDYING CHRONIC INFECTIONS AND ONCOGENIC PROCESSES IN THE LIVER. 2022 16 1334 25 DEREGULATION OF AIOLOS EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS THAT ARE RESISTANT TO APOPTOSIS. AIOLOS, A MEMBER OF THE IKAROS FAMILY OF ZINC-FINGER TRANSCRIPTION FACTORS, PLAYS AN IMPORTANT ROLE IN THE CONTROL OF MATURE B LYMPHOCYTE DIFFERENTIATION AND MATURATION. IN THIS STUDY, WE SHOWED THAT AIOLOS EXPRESSION IS UP-REGULATED IN B-CLL CELLS. THIS OVEREXPRESSION DOES NOT IMPLICATE ISOFORM IMBALANCE OR DISTURB AIOLOS SUBCELLULAR LOCALIZATION. THE CHROMATIN STATUS AT THE AIOLOS PROMOTER IN CLL IS DEFINED BY THE DEMETHYLATION OF DNA AND AN ENRICHMENT OF EUCHROMATIN ASSOCIATED HISTONE MARKERS, SUCH AS THE DIMETHYLATION OF THE LYSINE 4 ON HISTONE H3. THESE EPIGENETIC MODIFICATIONS SHOULD ALLOW ITS UPSTREAM EFFECTORS, SUCH AS NUCLEAR FACTOR-KAPPAB, CONSTITUTIVELY ACTIVATED IN CLL, TO GAIN ACCESS TO PROMOTER, RESULTING UP-REGULATION OF AIOLOS. TO DETERMINE THE CONSEQUENCES OF AIOLOS DEREGULATION IN CLL, WE ANALYZED THE EFFECTS OF AIOLOS OVEREXPRESSION OR DOWN-REGULATION ON APOPTOSIS. AIOLOS IS INVOLVED IN CELL SURVIVAL BY REGULATING THE EXPRESSION OF SOME BCL-2 FAMILY MEMBERS. OUR RESULTS STRONGLY SUGGEST THAT AIOLOS DEREGULATION BY EPIGENETIC MODIFICATIONS MAY BE A HALLMARK OF CLL. 2011 17 3941 30 LNCRNA DRAIR IS DOWNREGULATED IN DIABETIC MONOCYTES AND MODULATES THE INFLAMMATORY PHENOTYPE VIA EPIGENETIC MECHANISMS. LONG NONCODING RNAS (LNCRNAS) ARE INCREASINGLY IMPLICATED IN THE PATHOLOGY OF DIABETIC COMPLICATIONS. HERE, WE EXAMINED THE ROLE OF LNCRNAS IN MONOCYTE DYSFUNCTION AND INFLAMMATION ASSOCIATED WITH HUMAN TYPE 2 DIABETES MELLITUS (T2D). RNA SEQUENCING ANALYSIS OF CD14+ MONOCYTES FROM PATIENTS WITH T2D VERSUS HEALTHY CONTROLS REVEALED DOWNREGULATION OF ANTIINFLAMMATORY AND ANTIPROLIFERATIVE GENES, ALONG WITH SEVERAL LNCRNAS, INCLUDING A POTENTIALLY NOVEL DIVERGENT LNCRNA DIABETES REGULATED ANTIINFLAMMATORY RNA (DRAIR) AND ITS NEARBY GENE CPEB2. HIGH GLUCOSE AND PALMITIC ACID DOWNREGULATED DRAIR IN CULTURED CD14+ MONOCYTES, WHEREAS ANTIINFLAMMATORY CYTOKINES AND MONOCYTE-TO-MACROPHAGE DIFFERENTIATION UPREGULATED DRAIR VIA KLF4 TRANSCRIPTION FACTOR. DRAIR OVEREXPRESSION INCREASED ANTIINFLAMMATORY AND MACROPHAGE DIFFERENTIATION GENES BUT INHIBITED PROINFLAMMATORY GENES. CONVERSELY, DRAIR KNOCKDOWN ATTENUATED ANTIINFLAMMATORY GENES, PROMOTED INFLAMMATORY RESPONSES, AND INHIBITED PHAGOCYTOSIS. DRAIR REGULATED TARGET GENE EXPRESSION THROUGH INTERACTION WITH CHROMATIN, AS WELL AS INHIBITION OF THE REPRESSIVE EPIGENETIC MARK H3K9ME2 AND ITS CORRESPONDING METHYLTRANSFERASE G9A. MOUSE ORTHOLOGOUS DRAIR AND CPEB2 WERE ALSO DOWNREGULATED IN PERITONEAL MACROPHAGES FROM T2D DB/DB MICE, AND DRAIR KNOCKDOWN IN NONDIABETIC MICE ENHANCED PROINFLAMMATORY GENES IN MACROPHAGES. THUS, DRAIR MODULATES THE INFLAMMATORY PHENOTYPE OF MONOCYTES/MACROPHAGES VIA EPIGENETIC MECHANISMS, AND ITS DOWNREGULATION IN T2D MAY PROMOTE CHRONIC INFLAMMATION. AUGMENTATION OF ENDOGENOUS LNCRNAS LIKE DRAIR COULD SERVE AS NOVEL ANTIINFLAMMATORY THERAPIES FOR DIABETIC COMPLICATIONS. 2021 18 238 25 ADENOSINE KINASE: A KEY REGULATOR OF PURINERGIC PHYSIOLOGY. ADENOSINE (ADO) IS AN ESSENTIAL BIOMOLECULE FOR LIFE THAT PROVIDES CRITICAL REGULATION OF ENERGY UTILIZATION AND HOMEOSTASIS. ADENOSINE KINASE (ADK) IS AN EVOLUTIONARY ANCIENT RIBOKINASE DERIVED FROM BACTERIAL SUGAR KINASES THAT IS WIDELY EXPRESSED IN ALL FORMS OF LIFE, TISSUES AND ORGAN SYSTEMS THAT TIGHTLY REGULATES INTRACELLULAR AND EXTRACELLULAR ADO CONCENTRATIONS. THE FACILE ABILITY OF ADK TO ALTER ADO AVAILABILITY PROVIDES A "SITE AND EVENT" SPECIFICITY TO THE ENDOGENOUS PROTECTIVE EFFECTS OF ADO IN SITUATIONS OF CELLULAR STRESS. IN ADDITION TO MODULATING THE ABILITY OF ADO TO ACTIVATE ITS COGNATE RECEPTORS (P1 RECEPTORS), NUCLEAR ADK ISOFORM ACTIVITY HAS BEEN LINKED TO EPIGENETIC MECHANISMS BASED ON TRANSMETHYLATION PATHWAYS. PREVIOUS DRUG DISCOVERY RESEARCH HAS TARGETED ADK INHIBITION AS A THERAPEUTIC APPROACH TO MANAGE EPILEPSY, PAIN, AND INFLAMMATION. THESE EFFORTS GENERATED MULTIPLE CLASSES OF HIGHLY POTENT AND SELECTIVE INHIBITORS. HOWEVER, CLINICAL DEVELOPMENT OF EARLY ADK INHIBITORS WAS STOPPED DUE TO APPARENT MECHANISTIC TOXICITY AND THE LACK OF SUITABLE TRANSLATIONAL MARKERS. NEW INSIGHTS REGARDING THE POTENTIAL ROLE OF THE NUCLEAR ADK ISOFORM (ADK-LONG) IN THE EPIGENETIC MODULATION OF MALADAPTIVE DNA METHYLATION OFFERS THE POSSIBILITY OF IDENTIFYING NOVEL ADK-ISOFORM SELECTIVE INHIBITORS AND NEW INTERVENTIONAL STRATEGIES THAT ARE INDEPENDENT OF ADO RECEPTOR ACTIVATION. 2021 19 1806 31 EFFECT OF TRANSCRIPTION INHIBITION AND GENERATION OF SUPPRESSIVE VIRAL NON-CODING RNAS. BACKGROUND: HIV-1 PATIENTS RECEIVING COMBINATION ANTIRETROVIRAL THERAPY (CART) SURVIVE INFECTION BUT REQUIRE LIFE-LONG ADHERENCE AT HIGH EXPENSE. IN CHRONIC CART-TREATED PATIENTS WITH UNDETECTABLE VIRAL TITERS, CELL-ASSOCIATED VIRAL RNA IS STILL DETECTABLE, POINTING TO LOW-LEVEL VIRAL TRANSCRIPTIONAL LEAKINESS. TO DATE, THERE ARE NO FDA-APPROVED DRUGS AGAINST HIV-1 TRANSCRIPTION. WE HAVE PREVIOUSLY SHOWN THAT F07#13, A THIRD GENERATION TAT PEPTIDE MIMETIC WITH COMPETITIVE ACTIVITY AGAINST CDK9/T1-TAT BINDING SITES, INHIBITS HIV-1 TRANSCRIPTION IN VITRO AND IN VIVO. RESULTS: HERE, WE DEMONSTRATE THAT INCREASING CONCENTRATIONS OF F07#13 (0.01, 0.1, 1 MICROM) CAUSE A DECREASE IN TAT LEVELS IN A DOSE-DEPENDENT MANNER BY INHIBITING THE CDK9/T1-TAT COMPLEX FORMATION AND SUBSEQUENT UBIQUITIN-MEDIATED TAT SEQUESTRATION AND DEGRADATION. OUR DATA INDICATE THAT COMPLEXES I AND IV CONTAIN DISTINCT PATTERNS OF UBIQUITINATED TAT AND THAT TRANSCRIPTIONAL INHIBITION INDUCED BY F07#13 CAUSES AN OVERALL REDUCTION IN TAT LEVELS. THIS REDUCTION MAY BE TRIGGERED BY F07#13 BUT ULTIMATELY IS MEDIATED BY TAR-GAG VIRAL RNAS THAT BIND SUPPRESSIVE TRANSCRIPTION FACTORS (SIMILAR TO 7SK, NRON, HOTAIR, AND XIST LNCRNAS) TO ENHANCE TRANSCRIPTIONAL GENE SILENCING AND LATENCY. THESE RNAS COMPLEX WITH PRC2, SIN3A, AND CUL4B, RESULTING IN EPIGENETIC MODIFICATIONS. FINALLY, WE OBSERVED AN F07#13-MEDIATED DECREASE OF VIRAL BURDEN BY TARGETING THE R REGION OF THE LONG TERMINAL REPEAT (HIV-1 PROMOTER REGION, LTR), PROMOTING BOTH PAUSED POLYMERASES AND INCREASED EFFICIENCY OF CRISPR/CAS9 EDITING IN INFECTED CELLS. THIS IMPLIES THAT GENE EDITING MAY BE BEST PERFORMED UNDER A REPRESSED TRANSCRIPTIONAL STATE. CONCLUSIONS: COLLECTIVELY, OUR RESULTS INDICATE THAT F07#13, WHICH CAN TERMINATE RNA POLYMERASE II AT DISTINCT SITES, CAN GENERATE SCAFFOLD RNAS, WHICH MAY ASSEMBLE INTO SPECIFIC SETS OF "RNA MACHINES" THAT CONTRIBUTE TO GENE REGULATION. IT REMAINS TO BE SEEN WHETHER THESE EFFECTS CAN ALSO BE SEEN IN VARIOUS CLADES THAT HAVE VARYING PROMOTER STRENGTH, MUTANT LTRS, AND IN PATIENT SAMPLES. 2019 20 6636 40 UNRAVELING A NEW PLAYER IN MULTIPLE SCLEROSIS PATHOGENESIS: THE RNA-BINDING PROTEIN HUR. BACKGROUND: ELAV-LIKE PROTEINS ARE A SMALL FAMILY OF RNA-BINDING PROTEINS THAT ARE FUNDAMENTAL PLAYERS IN POST-TRANSCRIPTIONAL MECHANISMS AND ARE INVOLVED IN THE PATHOGENESIS OF NEUROLOGIC AND PSYCHIATRIC DISORDERS. HUR, THE UBIQUITOUSLY EXPRESSED MEMBER OF THE FAMILY, IS ALSO IMPLICATED IN SUSTAINING INFLAMMATION AND INFLAMMATORY DISEASES, SUPPORTING THE PRODUCTION OF PRO-INFLAMMATORY CYTOKINES. INFLAMMATION PLAYS A CENTRAL ROLE IN MULTIPLE SCLEROSIS (MS), WHICH REPRESENTS THE MOST COMMON CAUSE OF PERMANENT PHYSICAL DISABILITY IN YOUNG ADULTS. MS IS A CHRONIC AUTOIMMUNE DISEASE AFFECTING THE CENTRAL NERVOUS SYSTEM, WITH A COMPLEX AETIOLOGY INVOLVING GENETIC, ENVIRONMENTAL AND EPIGENETIC FACTORS. NO DATA ARE AVAILABLE ON THE POTENTIAL ENTANGLEMENT OF HUR IN MS PATHOGENESIS IN PATIENTS. IN THE PRESENT WORK, WE AIMED AT EXPLORING HUR PROTEIN LEVELS IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) FROM MS PATIENTS, COMPARED TO HEALTHY CONTROLS. TO FURTHER ELUCIDATE THE POSSIBLE INVOLVEMENT OF HUR IN MS, WE ALSO INVESTIGATED THE RELATIONSHIP BETWEEN THIS SPECIFIC RNA-BINDING PROTEIN AND HSP70-2 PROTEIN, ALSO CONSIDERING THE HSP70-2 RS1061581 POLYMORPHISM, GIVEN THAT HSP70-2 MRNA HAS BEEN REPORTED AS A HUR TARGET AND THIS SPECIFIC POLYMORPHISM TO BE ASSOCIATED WITH MS RISK. METHODS: ALLELES AND GENOTYPES FOR HSP70-2 RS1061581 POLYMORPHISM WERE ASSESSED, BY USING A POLYMERASE CHAIN REACTION-RESTRICTION FRAGMENT LENGTH POLYMORPHISM, FOLLOWED BY DIGESTION WITH RESTRICTION ENZYME, IN MS PATIENTS AND HEALTHY CONTROLS. PBMCS FROM A SUBGROUP OF PATIENTS AND CONTROLS WERE USED TO EVALUATE HUR AND HSP70-2 PROTEIN CONTENT BY WESTERN BLOT. RESULTS: PBMCS FROM 52 MS PATIENTS HAD A LOWER HUR AND HIGHER HSP70-2 PROTEIN CONTENT COMPARED TO 43 HEALTHY CONTROLS. AN INCREASE OF 100 UNITS OF HUR SIGNIFICANTLY DECREASED THE RISK OF DEVELOPING MS BY 9.8% (OR: 0.902, 95% CI: 0.83-0.98), CONTROLLING FOR HSP70-2 PROTEIN EXPRESSION, HSP70-2 RS1061581 GENOTYPE, AGE AND SEX. MOREOVER, HOLDING HUR LEVELS, AN INCREASE OF 100 UNITS OF HSP70-2 PROTEIN SIGNIFICANTLY INCREASED THE MS RISK BY 18.1% (OR: 1.181, 95% CI: 1.03-1.36) AND THE GENETIC SUSCEPTIBILITY OF DEVELOPING MS FOR HSP70-2 RS1061581 GG CARRIERS IS CONFIRMED. OF INTEREST, MS PATIENTS WITH A MODERATE TO SEVERE FORM OF MS (MSSS >/= 3) SHOWED A TREND TOWARDS A REDUCTION OF HUR PROTEIN LEVELS COMPARED TO PATIENTS WITH MILD DISEASE SEVERITY (MSSS < 3). CONCLUSIONS: HUR PROTEIN LEVELS ARE REDUCED IN MS PATIENTS COMPARED TO HEALTHY SUBJECTS, AND THE PROTEIN AMOUNT MAY CONTINUE TO DECLINE WITH DISEASE PROGRESSION, SUGGESTING A PUTATIVE ROLE OF THIS RNA-BINDING PROTEIN. MOREOVER, OUR RESULTS SUGGEST THAT MS PATHOLOGY MAY HAVE DISRUPTED THE LINK BETWEEN HUR AND ITS TARGET TRANSCRIPT HSP70-2. IT WILL BE IMPORTANT TO FURTHER EXPLORE THE EXACT ROLE OF HUR IN MS, CONSIDERING THE COMPLEX INTERPLAY WITH OTHER RNA-BINDING FACTORS AND TARGET MRNAS. 2020