1 1129 131 COMPREHENSIVE ANALYSIS OF MRNA-LNCRNA CO-EXPRESSION PROFILES IN MOUSE BRAIN DURING INFECTION WITH TOXOPLASMA GONDII. TOXOPLASMA GONDII IS AN OBLIGATE INTRACELLULAR PROTOZOAN PARASITE WHICH SERIOUSLY THREATENS THE HEALTH OF DOMESTIC ANIMALS AND HUMANS. LONG NON-CODING RNAS (LNCRNAS) ARE NON-PROTEIN-CODING TRANSCRIPTS GREATER THAN 200 NUCLEOTIDES, WHICH ARE WIDELY INVOLVED IN TRANSCRIPTIONAL AND EPIGENETIC REGULATIONS. HOWEVER, LITTLE IS KNOWN ABOUT THE ROLES OF HOST LNCRNAS IN THE RESPONSE TO T. GONDII INFECTIONS. IN THIS STUDY, USING ILLUMINA SEQUENCING TECHNOLOGY, WE ANALYZED THE EXPRESSION PROFILES OF MRNAS AND LNCRNAS IN BALB/C MOUSE BRAIN FOLLOWING INFECTION BY T. GONDII PRU STRAIN (TYPE II GENOTYPE) CYSTS. THE IDENTIFIED DIFFERENTIALLY EXPRESSED (DE) RNAS WERE SUBJECTED TO BIOINFORMATICS ANALYSIS. A TOTAL OF 2,090 ANNOTATED LNCRNAS ALONG WITH 3,577 NOVEL LNCRNAS WERE IDENTIFIED. IN THE ACUTELY INFECTED MOUSE BRAIN, A TOTAL OF 330 MRNAS AND 19 LNCRNAS WERE DYS-REGULATED, WHEREAS 136 DE MRNAS AND 9 DE LNCRNAS WERE IDENTIFIED IN CHRONICALLY INFECTED MOUSE BRAIN. GO ANALYSIS REVEALED THAT THESE DE MRNAS IDENTIFIED AT ACUTE INFECTION STAGE WERE INVOLVED IN IMMUNE RESPONSE, WHEREAS DE MRNAS FOUND AT CHRONIC INFECTION STAGE WERE MOSTLY ENRICHED IN RESPONSE TO PROTOZOAN. KEGG ANALYSIS SHOWED THAT DE MRNAS WERE SIGNIFICANTLY ENRICHED IN DISEASE RELATED PATHWAYS. IN ADDITION, THE PUTATIVE MRNA-LNCRNA CO-EXPRESSION NETWORK WAS CONSTRUCTED, AND SEVERAL HUB REGULATORY RNAS WERE IDENTIFIED BASED ON THE TRANSCRIPTOME DATA. THIS STUDY FIRSTLY CHARACTERIZED THE CO-EXPRESSION PROFILE OF MRNAS AND LNCRNAS IN MOUSE BRAIN INFECTED WITH T. GONDII AND PROVIDED A FRAMEWORK FOR FURTHER STUDIES OF THE ROLES OF LNCRNAS IN HOST NEUROPATHOLOGY DURING TOXOPLASMOSIS PROGRESSION. 2023 2 5970 22 TESTOSTERONE ACTS WITHIN THE MEDIAL AMYGDALA OF RATS TO REDUCE INNATE FEAR TO PREDATOR ODOR AKIN TO THE EFFECTS OF TOXOPLASMA GONDII INFECTION. RATS INFECTED WITH THE PROTOZOAN TOXOPLASMA GONDII EXHIBIT A REDUCED AVERSION TO CAT ODOR. THIS BEHAVIORAL CHANGE IS THOUGHT TO INCREASE TROPHIC TRANSMISSION OF THE PARASITE. INFECTED MALE RATS ALSO SHOW A GREATER TESTICULAR SYNTHESIS OF TESTOSTERONE AND EPIGENETIC CHANGE IN ARGININE VASOPRESSIN WITHIN THE MEDIAL AMYGDALA. HERE, WE SHOW THAT EXOGENOUS SUPPLY OF TESTOSTERONE WITHIN MEA OF UNINFECTED CASTRATES RECAPITULATES REDUCTION IN INNATE FEAR AKIN TO BEHAVIORAL CHANGE ATTRIBUTED TO THE PARASITE. WE ALSO SHOW THAT CASTRATION POST ESTABLISHMENT OF CHRONIC INFECTION PRECLUDES CHANGES IN FEAR AND MEDIAL AMYGDALA ARGININE VASOPRESSIN IN THE INFECTED MALE RATS. THESE OBSERVATIONS SUPPORT THE ROLE OF GONADAL HORMONES AND PURSUANT NEUROENDOCRINE CHANGES IN MEDIATING THE LOSS OF FEAR IN THE INFECTED RATS. THIS WORK ALSO DEMONSTRATES THAT TESTOSTERONE ACTING SPECIFICALLY WITHIN THE MEDIAL AMYGDALA SUFFICIENTLY EXPLAINS REDUCED DEFENSIVE BEHAVIORS OFTEN OBSERVED DURING THE APPETITIVE COMPONENT OF REPRODUCTIVE BEHAVIORS. 2020 3 6749 41 WHOLE-GENOME CARDIAC DNA METHYLATION FINGERPRINT AND GENE EXPRESSION ANALYSIS PROVIDE NEW INSIGHTS IN THE PATHOGENESIS OF CHRONIC CHAGAS DISEASE CARDIOMYOPATHY. BACKGROUND: CHAGAS DISEASE, CAUSED BY THE PROTOZOAN TRYPANOSOMA CRUZI, IS ENDEMIC IN LATIN AMERICA AND AFFECTS 10 MILLION PEOPLE WORLDWIDE. APPROXIMATELY 12000 DEATHS ATTRIBUTABLE TO CHAGAS DISEASE OCCUR ANNUALLY DUE TO CHRONIC CHAGAS DISEASE CARDIOMYOPATHY (CCC), AN INFLAMMATORY CARDIOMYOPATHY PRESENTING WITH HEART FAILURE AND ARRYTHMIA; 30% OF INFECTED SUBJECTS DEVELOP CCC YEARS AFTER INFECTION. GENETIC MECHANISMS PLAY A ROLE IN DIFFERENTIAL PROGRESSION TO CCC, BUT LITTLE IS KNOWN ABOUT THE ROLE OF EPIGENETIC MODIFICATIONS IN PATHOLOGICAL GENE EXPRESSION PATTERNS IN CCC PATIENTS' MYOCARDIUM. DNA METHYLATION IS THE MOST COMMON MODIFICATION IN THE MAMMALIAN GENOME. METHODS: WE INVESTIGATED THE IMPACT OF GENOME-WIDE CARDIAC DNA METHYLATION ON GLOBAL GENE EXPRESSION IN MYOCARDIAL SAMPLES FROM END-STAGE CCC PATIENTS, COMPARED TO CONTROL SAMPLES FROM ORGAN DONORS. RESULTS: IN TOTAL, 4720 GENES WERE DIFFERENTIALLY METHYLATED BETWEEN CCC PATIENTS AND CONTROLS, OF WHICH 399 WERE ALSO DIFFERENTIALLY EXPRESSED. SEVERAL OF THEM WERE RELATED TO HEART FUNCTION OR TO THE IMMUNE RESPONSE AND HAD METHYLATION SITES IN THEIR PROMOTER REGION. REPORTER GENE AND IN SILICO TRANSCRIPTION FACTOR BINDING ANALYSES INDICATED PROMOTER METHYLATION MODIFIED EXPRESSION OF KEY GENES. AMONG THOSE, WE FOUND POTASSIUM CHANNEL GENES KCNA4 AND KCNIP4, INVOLVED IN ELECTRICAL CONDUCTION AND ARRYTHMIA, SMOC2, INVOLVED IN MATRIX REMODELING, AS WELL AS ENKEPHALIN AND RUNX3, POTENTIALLY INVOLVED IN THE INCREASED T-HELPER 1 CYTOKINE-MEDIATED INFLAMMATORY DAMAGE IN HEART. CONCLUSIONS: RESULTS SUPPORT THAT DNA METHYLATION PLAYS A ROLE IN THE REGULATION OF EXPRESSION OF PATHOGENICALLY RELEVANT GENES IN CCC MYOCARDIUM, AND IDENTIFY NOVEL POTENTIAL DISEASE PATHWAYS AND THERAPEUTIC TARGETS IN CCC. 2017 4 2375 33 EPIGENETIC REGULATION OF TRANSCRIPTION FACTOR BINDING MOTIFS PROMOTES TH1 RESPONSE IN CHAGAS DISEASE CARDIOMYOPATHY. CHAGAS DISEASE, CAUSED BY THE PROTOZOAN TRYPANOSOMA CRUZI, IS AN ENDEMIC PARASITIC DISEASE OF LATIN AMERICA, AFFECTING 7 MILLION PEOPLE. ALTHOUGH MOST PATIENTS ARE ASYMPTOMATIC, 30% DEVELOP COMPLICATIONS, INCLUDING THE OFTEN-FATAL CHRONIC CHAGASIC CARDIOMYOPATHY (CCC). ALTHOUGH PREVIOUS STUDIES HAVE DEMONSTRATED SOME GENETIC DEREGULATIONS ASSOCIATED WITH CCCS, THE CAUSES OF THEIR DEREGULATIONS REMAIN POORLY DESCRIBED. BASED ON BULK RNA-SEQ AND WHOLE GENOME DNA METHYLATION DATA, WE INVESTIGATED THE GENETIC AND EPIGENETIC DEREGULATIONS PRESENT IN THE MODERATE AND SEVERE STAGES OF CCC. ANALYSIS OF HEART TISSUE GENE EXPRESSION PROFILE ALLOWED US TO IDENTIFY 1407 DIFFERENTIALLY EXPRESSED TRANSCRIPTS (DEGS) SPECIFIC FROM CCC PATIENTS. A TISSUE DNA METHYLATION ANALYSIS DONE ON THE SAME TISSUE HAS PERMITTED THE IDENTIFICATION OF 92 REGULATORY DIFFERENTIALLY METHYLATED REGIONS (DMR) LOCALIZED IN THE PROMOTER OF DEGS. AN IN-DEPTH STUDY OF THE TRANSCRIPTION FACTORS BINDING SITES (TFBS) IN THE DMRS CORROBORATED THE IMPORTANCE OF TFBS'S DNA METHYLATION FOR GENE EXPRESSION IN CCC MYOCARDIUM. TBX21, RUNX3 AND EBF1 ARE THE TRANSCRIPTION FACTORS WHOSE BINDING MOTIF APPEARS TO BE AFFECTED BY DNA METHYLATION IN THE LARGEST NUMBER OF GENES. BY COMBINING BOTH TRANSCRIPTOMIC AND METHYLOMIC ANALYSIS ON HEART TISSUE, AND METHYLOMIC ANALYSIS ON BLOOD, 4 BIOLOGICAL PROCESSES AFFECTED BY SEVERE CCC HAVE BEEN IDENTIFIED, INCLUDING IMMUNE RESPONSE, ION TRANSPORT, CARDIAC MUSCLE PROCESSES AND NERVOUS SYSTEM. AN ADDITIONAL STUDY ON BLOOD METHYLATION OF MODERATE CCC SAMPLES PUT FORWARD THE IMPORTANCE OF ION TRANSPORT AND NERVOUS SYSTEM IN THE DEVELOPMENT OF THE DISEASE. 2022 5 370 39 AN APICOMPLEXAN BROMODOMAIN PROTEIN, TGBDP1, ASSOCIATES WITH DIVERSE EPIGENETIC FACTORS TO REGULATE ESSENTIAL TRANSCRIPTIONAL PROCESSES IN TOXOPLASMA GONDII. THE PROTOZOAN PATHOGEN TOXOPLASMA GONDII RELIES ON TIGHT REGULATION OF GENE EXPRESSION TO INVADE AND ESTABLISH INFECTION IN ITS HOST. THE DIVERGENT GENE REGULATORY MECHANISMS OF TOXOPLASMA AND RELATED APICOMPLEXAN PATHOGENS RELY HEAVILY ON REGULATORS OF CHROMATIN STRUCTURE AND HISTONE MODIFICATIONS. THE IMPORTANT CONTRIBUTION OF HISTONE ACETYLATION FOR TOXOPLASMA IN BOTH ACUTE AND CHRONIC INFECTION HAS BEEN DEMONSTRATED, WHERE HISTONE ACETYLATION INCREASES AT ACTIVE GENE LOCI. HOWEVER, THE DIRECT CONSEQUENCES OF SPECIFIC HISTONE ACETYLATION MARKS AND THE CHROMATIN PATHWAY THAT INFLUENCES TRANSCRIPTIONAL REGULATION IN RESPONSE TO THE MODIFICATION ARE UNCLEAR. AS A READER OF LYSINE ACETYLATION, THE BROMODOMAIN SERVES AS A MEDIATOR BETWEEN THE ACETYLATED HISTONE AND TRANSCRIPTIONAL REGULATORS. HERE WE SHOW THAT THE BROMODOMAIN PROTEIN, TGBDP1, WHICH IS CONSERVED AMONG APICOMPLEXA AND WITHIN THE ALVEOLATA SUPERPHYLUM, IS ESSENTIAL FOR TOXOPLASMA ASEXUAL PROLIFERATION. USING CLEAVAGE UNDER TARGETS AND TAGMENTATION, WE DEMONSTRATE THAT TGBDP1 IS RECRUITED TO TRANSCRIPTIONAL START SITES OF A LARGE PROPORTION OF PARASITE GENES. TRANSCRIPTIONAL PROFILING DURING TGBDP1 KNOCKDOWN REVEALED THAT LOSS OF TGBDP1 LEADS TO MAJOR DYSREGULATION OF GENE EXPRESSION, IMPLYING MULTIPLE ROLES FOR TGBDP1 IN BOTH GENE ACTIVATION AND REPRESSION. THIS IS SUPPORTED BY INTERACTOME ANALYSIS OF TGBDP1 DEMONSTRATING THAT TGBDP1 FORMS A CORE COMPLEX WITH TWO OTHER BROMODOMAIN PROTEINS AND AN APIAP2 FACTOR. THIS CORE COMPLEX APPEARS TO INTERACT WITH OTHER EPIGENETIC FACTORS SUCH AS NUCLEOSOME REMODELING COMPLEXES. WE CONCLUDE THAT TGBDP1 INTERACTS WITH DIVERSE EPIGENETIC REGULATORS TO EXERT OPPOSING INFLUENCES ON GENE EXPRESSION IN THE TOXOPLASMA TACHYZOITE. IMPORTANCE HISTONE ACETYLATION IS CRITICAL FOR PROPER REGULATION OF GENE EXPRESSION IN THE SINGLE-CELLED EUKARYOTIC PATHOGEN TOXOPLASMA GONDII. BROMODOMAIN PROTEINS ARE "READERS" OF HISTONE ACETYLATION AND MAY LINK THE MODIFIED CHROMATIN TO TRANSCRIPTION FACTORS. HERE, WE SHOW THAT THE BROMODOMAIN PROTEIN TGBDP1 IS ESSENTIAL FOR PARASITE SURVIVAL AND THAT LOSS OF TGBDP1 RESULTS IN GLOBAL DYSREGULATION OF GENE EXPRESSION. TGBDP1 IS RECRUITED TO THE PROMOTER REGION OF A LARGE PROPORTION OF PARASITE GENES, FORMS A CORE COMPLEX WITH TWO OTHER BROMODOMAIN PROTEINS, AND INTERACTS WITH DIFFERENT TRANSCRIPTIONAL REGULATORY COMPLEXES. WE CONCLUDE THAT TGBDP1 IS A KEY FACTOR FOR SENSING SPECIFIC HISTONE MODIFICATIONS TO INFLUENCE MULTIPLE FACETS OF TRANSCRIPTIONAL REGULATION IN TOXOPLASMA GONDII. 2023 6 5125 31 POST-TRANSLATIONAL MODIFICATIONS OF TRYPANOSOMA CRUZI CANONICAL AND VARIANT HISTONES. CHAGAS DISEASE, CAUSED BY TRYPANOSOMA CRUZI, STILL AFFECTS MILLIONS OF PEOPLE AROUND THE WORLD. NO VACCINES NOR TREATMENT FOR CHRONIC CHAGAS DISEASE ARE AVAILABLE, AND CHEMOTHERAPY FOR THE ACUTE PHASE IS HINDERED BY LIMITED EFFICACY AND SEVERE SIDE EFFECTS. THE PROCESSES BY WHICH THE PARASITE ACQUIRES INFECTIVITY AND SURVIVES IN DIFFERENT HOSTS INVOLVE TIGHT REGULATION OF GENE EXPRESSION, MAINLY POST-TRANSCRIPTIONALLY. NEVERTHELESS, CHROMATIN STRUCTURE/ORGANIZATION OF TRYPANOSOMATIDS IS SIMILAR TO OTHER EUKARYOTES, INCLUDING HISTONE VARIANTS AND POST-TRANSLATIONAL MODIFICATIONS. EMERGING EVIDENCE SUGGESTS THAT EPIGENETIC MECHANISMS ALSO PLAY AN IMPORTANT ROLE IN THE BIOLOGY/PATHOGENESIS OF THESE PARASITES, MAKING EPIGENETIC TARGETS SUITABLE CANDIDATES TO DRUG DISCOVERY. HERE, WE PRESENT THE FIRST COMPREHENSIVE MAP OF POST-TRANSLATIONAL MODIFICATIONS OF T. CRUZI CANONICAL AND VARIANT HISTONES AND SHOW THAT ITS HISTONE CODE CAN BE AS SOPHISTICATED AS THAT OF OTHER EUKARYOTES. A TOTAL OF 13 DISTINCT MODIFICATION TYPES WERE IDENTIFIED, INCLUDING RATHER NOVEL AND UNUSUAL ONES SUCH AS ALTERNATIVE LYSINE ACYLATIONS, SERINE/THREONINE ACETYLATION, AND N-TERMINAL METHYLATION. SOME HISTONE MARKS CORRELATE TO THOSE DESCRIBED FOR OTHER ORGANISMS, SUGGESTING THAT SIMILAR REGULATORY MECHANISMS MAY BE IN PLACE. OTHERS, HOWEVER, ARE UNIQUE TO T. CRUZI OR TO TRYPANOSOMATIDS AS A GROUP AND MIGHT REPRESENT GOOD CANDIDATES FOR THE DEVELOPMENT OF ANTIPARASITIC DRUGS. 2017 7 4573 28 MYOCARDIAL INFARCTION-ASSOCIATED TRANSCRIPT, A LONG NONCODING RNA, IS OVEREXPRESSED DURING DILATED CARDIOMYOPATHY DUE TO CHRONIC CHAGAS DISEASE. LONG NONCODING RNAS (LNCRNAS) MODULATE GENE EXPRESSION AT THE EPIGENETIC, TRANSCRIPTIONAL, AND POSTTRANSCRIPTIONAL LEVELS. DYSREGULATION OF THE LNCRNA KNOWN AS MYOCARDIAL INFARCTION-ASSOCIATED TRANSCRIPT (MIAT) HAS BEEN ASSOCIATED WITH MYOCARDIAL INFARCTION. CHAGAS DISEASE CAUSES A SEVERE INFLAMMATORY DILATED CHRONIC CARDIOMYOPATHY (CCC). WE INVESTIGATED THE ROLE OF MIAT IN CCC. A WHOLE-TRANSCRIPTOME ANALYSIS OF HEART BIOPSY SPECIMENS AND FORMALIN-FIXED, PARAFFIN-EMBEDDED SAMPLES REVEALED THAT MIAT WAS OVEREXPRESSED IN PATIENTS WITH CCC, COMPARED WITH SUBJECTS WITH NONINFLAMMATORY DILATED CARDIOMYOPATHY AND CONTROLS. THESE RESULTS WERE CONFIRMED IN A MOUSE MODEL. RESULTS SUGGEST THAT MIAT IS A SPECIFIC BIOMARKER OF CCC. 2016 8 1498 29 DNA METHYLATION ALTERATIONS CAUSED BY LEISHMANIA INFECTION MAY GENERATE A MICROENVIRONMENT PRONE TO TUMOUR DEVELOPMENT. DNA METHYLATION IS AN EPIGENETIC SIGNATURE CONSISTING OF A METHYL GROUP AT THE 5' CYTOSINE OF CPG DINUCLEOTIDES. MODIFICATIONS IN DNA METHYLATION PATTERN HAVE BEEN DETECTED IN CANCER AND INFECTIOUS DISEASES AND MAY BE ASSOCIATED WITH GENE EXPRESSION CHANGES. IN CANCER DEVELOPMENT DNA METHYLATION ABERRATIONS ARE EARLY EVENTS WHEREAS IN INFECTIOUS DISEASES THESE EPIGENETIC CHANGES MAY BE DUE TO HOST/PATHOGEN INTERACTION. IN PARTICULAR, IN LEISHMANIASIS, A PARASITIC DISEASE CAUSED BY THE PROTOZOAN LEISHMANIA, DNA METHYLATION ALTERATIONS HAVE BEEN DETECTED IN MACROPHAGES UPON INFECTION WITH LEISHMANIA DONOVANI AND IN SKIN LESIONS FROM PATIENTS WITH CUTANEOUS LEISHMANIASIS. INTERESTINGLY, DIFFERENT TYPES OF CANCERS, SUCH AS CUTANEOUS MALIGNANT LESIONS, LYMPHOMA AND HEPATOCELLULAR CARCINOMA, HAVE BEEN DIAGNOSED IN PATIENTS WITH A HISTORY OF LEISHMANIASIS. IN FACT, IT IS KNOWN THAT THERE EXISTS AN ASSOCIATION BETWEEN CANCER AND INFECTIOUS DISEASES. LEISHMANIA INFECTION MAY INCREASE SUSCEPTIBILITY TO DEVELOP CANCER, BUT THE MECHANISMS INVOLVED ARE NOT ENTIRELY CLEAR. CONSIDERING THESE ASPECTS, IN THIS REVIEW WE DISCUSS THE HYPOTHESIS THAT DNA METHYLATION ALTERATIONS INDUCED BY LEISHMANIA MAY TRIGGER TUMORIGENESIS IN LONG TERM INFECTION SINCE THESE EPIGENETIC MODIFICATIONS MAY ENHANCE AND ACCUMULATE DURING CHRONIC LEISHMANIASIS. 2022 9 6695 25 VARIANT GENE EXPRESSION AND ANTIGENIC VARIATION BY MALARIA PARASITES. MALARIA IS A SIGNIFICANT THREAT THROUGHOUT THE DEVELOPING WORLD. AMONG THE MOST FASCINATING ASPECTS OF THE PROTOZOAN PARASITES RESPONSIBLE FOR THIS DISEASE ARE THE METHODS THEY EMPLOY TO AVOID THE IMMUNE SYSTEM AND PERPETUATE CHRONIC INFECTIONS. KEY AMONG THESE IS ANTIGENIC VARIATION: BY SYSTEMATICALLY ALTERING ANTIGENS THAT ARE DISPLAYED TO THE HOST'S IMMUNE SYSTEM, THE PARASITE RENDERS THE ADAPTIVE IMMUNE RESPONSE INEFFECTIVE. FOR PLASMODIUM FALCIPARUM, THE SPECIES RESPONSIBLE FOR THE MOST SEVERE FORM OF HUMAN MALARIA, THIS PROCESS INVOLVES A COMPLICATED MOLECULAR MECHANISM THAT RESULTS IN CONTINUOUSLY CHANGING PATTERNS OF VARIANT-ANTIGEN-ENCODING GENE EXPRESSION. ALTHOUGH MANY FEATURES OF THIS PROCESS REMAIN OBSCURE, SIGNIFICANT PROGRESS HAS BEEN MADE IN RECENT YEARS TO DECIPHER VARIOUS MOLECULAR ASPECTS OF THE REGULATORY CASCADE THAT CAUSES CHRONIC INFECTION. 2017 10 3827 34 INVESTIGATION OF HETEROCHROMATIN PROTEIN 1 FUNCTION IN THE MALARIA PARASITE PLASMODIUM FALCIPARUM USING A CONDITIONAL DOMAIN DELETION AND SWAPPING APPROACH. THE HUMAN MALARIA PARASITE PLASMODIUM FALCIPARUM ENCODES A SINGLE ORTHOLOG OF HETEROCHROMATIN PROTEIN 1 (PFHP1) THAT PLAYS A CRUCIAL ROLE IN THE EPIGENETIC REGULATION OF VARIOUS SURVIVAL-RELATED PROCESSES. PFHP1 IS ESSENTIAL FOR PARASITE PROLIFERATION AND THE HERITABLE SILENCING OF GENES LINKED TO ANTIGENIC VARIATION, HOST CELL INVASION, AND SEXUAL CONVERSION. HERE, WE EMPLOYED CRISPR/CAS9-MEDIATED GENOME EDITING COMBINED WITH THE DICRE/LOXP SYSTEM TO INVESTIGATE HOW THE PFHP1 CHROMODOMAIN (CD), HINGE DOMAIN, AND CHROMOSHADOW DOMAIN (CSD) CONTRIBUTE TO OVERALL PFHP1 FUNCTION. WE SHOW THAT THE 76 C-TERMINAL RESIDUES ARE RESPONSIBLE FOR TARGETING PFHP1 TO THE NUCLEUS. FURTHERMORE, WE REVEAL THAT EACH OF THE THREE FUNCTIONAL DOMAINS OF PFHP1 ARE REQUIRED FOR HETEROCHROMATIN FORMATION, GENE SILENCING, AND MITOTIC PARASITE PROLIFERATION. FINALLY, WE DISCOVERED THAT THE HINGE DOMAIN AND CSD OF HP1 ARE FUNCTIONALLY CONSERVED BETWEEN P. FALCIPARUM AND P. BERGHEI, A RELATED MALARIA PARASITE INFECTING RODENTS. IN SUMMARY, OUR STUDY PROVIDES NEW INSIGHTS INTO PFHP1 FUNCTION AND OFFERS A TOOL FOR FURTHER STUDIES ON EPIGENETIC REGULATION AND LIFE CYCLE DECISION IN MALARIA PARASITES.IMPORTANCE MALARIA IS CAUSED BY UNICELLULAR PLASMODIUM SPECIES PARASITES THAT REPEATEDLY INVADE AND REPLICATE INSIDE RED BLOOD CELLS. SOME BLOOD-STAGE PARASITES EXIT THE CELL CYCLE AND DIFFERENTIATE INTO GAMETOCYTES THAT ARE ESSENTIAL FOR MALARIA TRANSMISSION VIA THE MOSQUITO VECTOR. EPIGENETIC CONTROL MECHANISMS ALLOW THE PARASITES TO ALTER THE EXPRESSION OF SURFACE ANTIGENS AND TO BALANCE THE SWITCH BETWEEN PARASITE MULTIPLICATION AND GAMETOCYTE PRODUCTION. THESE PROCESSES ARE CRUCIAL TO ESTABLISH CHRONIC INFECTION AND OPTIMIZE PARASITE TRANSMISSION. HERE, WE PERFORMED A MUTATIONAL ANALYSIS OF HETEROCHROMATIN PROTEIN 1 (HP1) IN P. FALCIPARUM WE DEMONSTRATE THAT ALL THREE DOMAINS OF THIS PROTEIN ARE INDISPENSABLE FOR THE PROPER FUNCTION OF HP1 IN PARASITE MULTIPLICATION, HETEROCHROMATIN FORMATION, AND GENE SILENCING. MOREOVER, EXPRESSION OF CHIMERIC PROTEINS REVEALED THE FUNCTIONAL CONSERVATION OF HP1 PROTEINS BETWEEN DIFFERENT PLASMODIUM SPECIES. THESE RESULTS PROVIDE NEW INSIGHT INTO THE FUNCTION AND EVOLUTION OF HP1 AS AN ESSENTIAL EPIGENETIC REGULATOR OF PARASITE SURVIVAL. 2021 11 3167 37 GROUP 1 METABOTROPIC GLUTAMATE RECEPTOR EXPRESSION DEFINES A T CELL MEMORY POPULATION DURING CHRONIC TOXOPLASMA INFECTION THAT ENHANCES IFN-GAMMA AND PERFORIN PRODUCTION IN THE CNS. WITHIN THE BRAIN, A PRO-INFLAMMATORY RESPONSE IS ESSENTIAL TO PREVENT CLINICAL DISEASE DUE TO TOXOPLASMA GONDII REACTIVATION. INFECTION IN THE IMMUNOCOMPROMISED LEADS TO LETHAL TOXOPLASMIC ENCEPHALITIS WHILE IN THE IMMUNOCOMPETENT, THERE IS PERSISTENT LOW-GRADE INFLAMMATION WHICH IS DEVOID OF CLINICAL SYMPTOMS. THIS SIGNIFIES THAT THERE IS A WELL-BALANCED AND REGULATED INFLAMMATORY RESPONSE TO T. GONDII IN THE BRAIN. T CELLS ARE THE DOMINANT IMMUNE CELLS THAT PREVENT CLINICAL DISEASE, AND THIS IS MEDIATED THROUGH THE SECRETION OF EFFECTOR MOLECULES SUCH AS PERFORINS AND IFN-GAMMA. THE PRESENCE OF COGNATE ANTIGEN, THE EXPRESSION OF SURVIVAL CYTOKINES, AND THE ALTERATION OF THE EPIGENETIC LANDSCAPE DRIVE THE DEVELOPMENT OF MEMORY T CELLS. HOWEVER, SPECIFIC EXTRINSIC SIGNALS THAT PROMOTE THE FORMATION AND MAINTENANCE OF MEMORY T CELLS WITHIN TISSUE ARE POORLY UNDERSTOOD. DURING CHRONIC INFECTION, THERE IS AN INCREASE IN EXTRACELLULAR GLUTAMATE THAT, DUE TO ITS FUNCTION AS AN EXCITATORY NEUROTRANSMITTER, IS NORMALLY TIGHTLY CONTROLLED IN THE CNS. HERE WE DEMONSTRATE THAT CD8(+) T CELLS FROM THE T. GONDII-INFECTED BRAIN PARENCHYMA ARE ENRICHED FOR METABOTROPIC GLUTAMATE RECEPTORS (MGLUR'S). CHARACTERIZATION STUDIES DETERMINED THAT MGLUR(+) EXPRESSION BY CD8(+) T CELLS DEFINES A DISTINCT MEMORY POPULATION AT THE TRANSCRIPTIONAL AND PROTEIN LEVEL. FINALLY, USING RECEPTOR ANTAGONISTS AND AGONISTS WE DEMONSTRATE MGLUR SIGNALING IS REQUIRED FOR OPTIMAL CD8(+) T CELL PRODUCTION OF THE EFFECTOR CYTOKINE IFNGAMMA. THIS WORK SUGGESTS THAT GLUTAMATE IS AN IMPORTANT ENVIRONMENTAL SIGNAL OF INFLAMMATION THAT PROMOTES T CELL FUNCTION. UNDERSTANDING GLUTAMATE'S INFLUENCE ON T CELLS IN THE BRAIN CAN PROVIDE INSIGHTS INTO THE MECHANISMS THAT GOVERN PROTECTIVE IMMUNITY AGAINST CNS-INFILTRATING PATHOGENS AND NEUROINFLAMMATION. 2023 12 1349 29 DETERMINANTS OF INNATE IMMUNITY IN VISCERAL LEISHMANIASIS AND THEIR IMPLICATION IN VACCINE DEVELOPMENT. LEISHMANIASIS IS ENDEMIC TO THE TROPICAL AND SUBTROPICAL REGIONS OF THE WORLD AND IS TRANSMITTED BY THE BITE OF AN INFECTED SAND FLY. THE MULTIFACETED INTERACTIONS BETWEEN LEISHMANIA, THE HOST INNATE IMMUNE CELLS, AND THE ADAPTIVE IMMUNITY DETERMINE THE SEVERITY OF PATHOGENESIS AND DISEASE DEVELOPMENT. LEISHMANIA PARASITES ESTABLISH A CHRONIC INFECTION BY SUBVERSION AND ATTENUATION OF THE MICROBICIDAL FUNCTIONS OF PHAGOCYTIC INNATE IMMUNE CELLS SUCH AS NEUTROPHILS, MACROPHAGES AND DENDRITIC CELLS (DCS). OTHER INNATE CELLS SUCH AS INFLAMMATORY MONOCYTES, MAST CELLS AND NK CELLS, ALSO CONTRIBUTE TO RESISTANCE AND/OR SUSCEPTIBILITY TO LEISHMANIA INFECTION. IN ADDITION TO THE CYTOKINE/CHEMOKINE SIGNALS FROM THE INNATE IMMUNE CELLS, RECENT STUDIES IDENTIFIED THE SUBTLE SHIFTS IN THE METABOLIC PATHWAYS OF THE INNATE CELLS THAT ACTIVATE DISTINCT IMMUNE SIGNAL CASCADES. THE NEXUS BETWEEN METABOLIC PATHWAYS, EPIGENETIC REPROGRAMMING AND THE IMMUNE SIGNALING CASCADES THAT DRIVE THE DIVERGENT INNATE IMMUNE RESPONSES, REMAINS TO BE FULLY UNDERSTOOD IN LEISHMANIA PATHOGENESIS. FURTHER, DEVELOPMENT OF SAFE AND EFFICACIOUS VACCINES AGAINST LEISHMANIASIS REQUIRES A BROADER UNDERSTANDING OF THE EARLY INTERACTIONS BETWEEN THE PARASITES AND INNATE IMMUNE CELLS. IN THIS REVIEW WE FOCUS ON THE CURRENT UNDERSTANDING OF THE SPECIFIC ROLE OF INNATE IMMUNE CELLS, THE METABOLOMIC AND EPIGENETIC REPROGRAMMING AND IMMUNE REGULATION THAT OCCURS DURING VISCERAL LEISHMANIASIS, AND THE STRATEGIES USED BY THE PARASITE TO EVADE AND MODULATE HOST IMMUNITY. WE HIGHLIGHT HOW SUCH PATHWAYS COULD BE EXPLOITED IN THE DEVELOPMENT OF SAFE AND EFFICACIOUS LEISHMANIA VACCINES. 2021 13 1718 38 DYSREGULATED LONG NON-CODING RNAS IN THE TEMPORAL LOBE EPILEPSY MOUSE MODEL. PURPOSE: TO PERFORM COMPREHENSIVE PROFILING OF LONG NON-CODING RNAS (LNCRNAS) IN TEMPORAL LOBE EPILEPSY. METHODS: WE PERFORMED EXTENSIVE PROFILING OF LNCRNAS AND MRNAS IN THE MOUSE PILOCARPINE MODEL IN SPECIFIC BRAIN REGIONS, THE HIPPOCAMPUS AND CORTEX, AND COMPARED THE RESULTS TO THOSE OF THE CONTROL MOUSE. DIFFERENTIALLY EXPRESSED LNCRNAS AND MRNAS WERE IDENTIFIED WITH A MICROARRAY ANALYSIS (ARRAYSTAR MOUSE LNCRNA EXPRESSION MICROARRAY V3.0). THEN, GENE ONTOLOGY (GO) AND PATHWAY ANALYSIS WERE PERFORMED TO INVESTIGATE THE POTENTIAL ROLES OF THE DIFFERENTIALLY EXPRESSED MRNAS IN THE PILOCARPINE MODEL. PROTEIN-PROTEIN INTERACTIONS TRANSCRIBED BY DYSREGULATED MRNAS WITH/WITHOUT CO-DYSREGULATED LNCRNAS WERE ANALYZED USING STRING V10 (HTTP://STRING-DB.ORG/). RESULTS: A TOTAL OF 22 AND 83 LNCRNAS WERE UP- AND DOWN-REGULATED (>/=2.0-FOLD, ALL P < .05), RESPECTIVELY, IN THE HIPPOCAMPUS OF THE EPILEPSY MODEL, WHILE 46 AND 659 LNCRNAS WERE UP- AND DOWN-REGULATED, RESPECTIVELY, IN THE CORTEX OF THE EPILEPSY MODEL. GO AND PATHWAY ANALYSIS REVEALED THAT THE DYSREGULATED MRNAS WERE CLOSELY ASSOCIATED WITH A PROCESS ALREADY KNOWN TO BE INVOLVED IN EPILEPTOGENESIS: ACUTE INFLAMMATION, CALCIUM ION REGULATION, EXTRACELLULAR MATRIX REMODELING, AND NEURONAL DIFFERENTIATION. AMONG THE LNCRNAS, WE IDENTIFIED 10 LNCRNAS COMMONLY DYSREGULATED WITH CORRESPONDING MRNAS IN THE CORTEX. THE STRING ANALYSIS SHOWED THAT THE DYSREGULATED MRNAS WERE INTERCONNECTED AROUND TWO CENTERS: THE MTOR PATHWAY-RELATED GENES AND REST PATHWAY-RELATED GENES. CONCLUSION: LNCRNAS WERE DYSREGULATED IN THE PILOCARPINE MOUSE MODEL ACCORDING TO THE BRAIN REGIONS OF THE HIPPOCAMPUS AND CORTEX. THE DYSREGULATED LNCRNAS WITH CO-DYSREGULATED MRNAS MIGHT BE POSSIBLE THERAPEUTIC TARGETS FOR THE EPIGENETIC REGULATION OF CHRONIC EPILEPSY. 2018 14 5096 31 PLASMODIUM FALCIPARUM SET2 DOMAIN IS ALLOSTERICALLY REGULATED BY ITS PHD-LIKE DOMAIN TO METHYLATE AT H3K36. THE ANTIGENIC VARIATION IS AN ESSENTIAL MECHANISM EMPLOYED BY THE MALARIA PARASITE TO ESTABLISH A CHRONIC INFECTION IN HUMANS. THREE MAJOR VIRULENT PROTEINS EMP1, RIFINS, AND STEVOR HAVE BEEN IMPLICATED IN CONTRIBUTING TO THE ANTIGENIC VARIATION PROCESS AND ARE ENCODED BY MULTIGENE FAMILIES IN PLASMODIUM SPP. THE KEY VIRULENCE FACTOR PFEMP1 IS ENCODED BY VAR GENES, AND IT EXHIBITS A MUTUALLY EXCLUSIVE TRANSCRIPTIONAL SWITCHING BETWEEN VAR GENES, ENSURING AN INDIVIDUAL PARASITE ONLY TRANSCRIBES A SINGLE VAR GENE AT A TIME. EXPRESSION OF VAR GENES IS TIGHTLY REGULATED BY TWO HISTONE EPIGENETIC METHYLATION MARKS H3K36ME3 AND H3K9ME3, OF WHICH THE H3K36ME3 MARK IS HIGHLY ENRICHED ON TRANSCRIPTION START SITES (TSSS) OF SUPPRESSED VAR GENES IN P. FALCIPARUM. HOWEVER, THE MECHANISMS OF H3K36ME3 MARK PROPAGATION ON ALL THE 59 VAR GENES OF P. FALCIPARUM ARE NOT KNOWN. HERE, WE HAVE IDENTIFIED A PHD (PLANT HOMEODOMAIN-LIKE DOMAIN) LIKE DOMAIN PRESENT WITHIN THE PFSET2 PROTEIN THAT SPECIFICALLY BINDS TO THE H3K36ME2 MARK, AN INTERMEDIATE PRODUCT OF THE H3K36ME3 MARK FORMATION ON THE NUCLEOSOME. SURPRISINGLY, WE HAVE FOUND THAT PHD - H3K36ME2 INTERACTION LEADS TO STIMULATION OF SET2 DOMAIN ACTIVITY ON THE NUCLEOSOME SUBSTRATES. THE ALLOSTERIC STIMULATION OF THE PFSET2 DOMAIN BY PHD-LIKE DOMAIN PRESENT WITHIN THE SAME PROTEIN SUGGESTS A NOVEL MECHANISM OF H3K36ME3 MARK PROPAGATION ON VAR GENES OF P. FALCIPARUM. THIS STUDY PROPOSES ALLOSTERIC REGULATION OF PFSET2 PROTEIN BY H3K36ME2 MARK AS AN ESSENTIAL MECHANISM OF VAR GENES SUPPRESSION TO ENSURE SUCCESSFUL ANTIGENIC VARIATION BY THE MALARIA PARASITE. 2021 15 6752 36 WIDESPREAD EXONIZATION OF TRANSPOSABLE ELEMENTS IN HUMAN CODING SEQUENCES IS ASSOCIATED WITH EPIGENETIC REGULATION OF TRANSCRIPTION. TRANSPOSABLE ELEMENTS (TES) HAVE LONG BEEN REGARDED AS SELFISH OR JUNK DNA HAVING LITTLE OR NO ROLE IN THE REGULATION OR FUNCTIONING OF THE HUMAN GENOME. HOWEVER, OVER THE PAST SEVERAL YEARS THIS VIEW CAME TO BE CHALLENGED AS SEVERAL STUDIES PROVIDED ANECDOTAL AS WELL AS GLOBAL EVIDENCE FOR THE CONTRIBUTION OF TES TO THE REGULATORY AND CODING NEEDS OF HUMAN GENES. IN THIS STUDY, WE EXPLORED THE INCORPORATION AND EPIGENETIC REGULATION OF CODING SEQUENCES DONATED BY TES USING GENE EXPRESSION AND OTHER ANCILLARY GENOMICS DATA FROM TWO HUMAN HEMATOPOIETIC CELL-LINES: GM12878 (A LYMPHOBLASTOID CELL LINE) AND K562 (A CHRONIC MYELOGENOUS LEUKEMIA CELL LINE). IN EACH CELL LINE, WE FOUND SEVERAL THOUSAND INSTANCES OF TES DONATING CODING SEQUENCES TO HUMAN GENES. WE COMPARED THE TRANSCRIPTOME ASSEMBLY OF THE RNA SEQUENCING (RNA-SEQ) READS WITH AND WITHOUT THE AID OF A REFERENCE TRANSCRIPTOME AND FOUND THAT THE PERCENTAGE OF GENES THAT INCORPORATE TES IN THEIR CODING SEQUENCES IS SIGNIFICANTLY GREATER THAN THAT OBTAINED FROM THE REFERENCE TRANSCRIPTOME ASSEMBLIES USING REFSEQ AND GENCODE GENE MODELS. WE ALSO USED HISTONE MODIFICATIONS CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ) DATA, CAP ANALYSIS OF GENE EXPRESSION (CAGE) DATA AND DNASEI HYPERSENSITIVITY SITE (DHS) DATA TO DEMONSTRATE THE EPIGENETIC REGULATION OF THE TE DERIVED CODING SEQUENCES. OUR RESULTS SUGGEST THAT TES FORM A SIGNIFICANTLY HIGHER PERCENTAGE OF CODING SEQUENCES THAN REPRESENTED IN GENE ANNOTATION DATABASES AND THESE TE DERIVED SEQUENCES ARE EPIGENETICALLY REGULATED IN ACCORDANCE WITH THEIR EXPRESSION IN THE TWO CELL TYPES. 2013 16 1989 34 EPIGENETIC ANALYSIS IN RHEUMATOID ARTHRITIS SYNOVIOCYTES. RHEUMATOID ARTHRITIS (RA) IS A COMPLEX CHRONIC SYSTEMATIC DISEASE WITH PROGRESSIVE DESTRUCTION OF THE JOINTS BY INVASIVE SYNOVIOCYTES. TO CHARACTERIZE THE KEY REGULATORS INVOLVED IN THE DEVELOPMENT OF RA, WE OBTAINED MULTILAYER EPIGENOMICS DATA INCLUDING DNA METHYLATION BY WHOLE-GENOME BISULFITE SEQUENCING, MIRNA PROFILES, GENETIC VARIATIONS BY WHOLE-EXOME SEQUENCING, AND MRNA PROFILES FROM SYNOVIOCYTES OF RA AND OSTEOARTHRITIS (OA) PATIENTS. THE OVERALL DNA METHYLATION PATTERNS WERE NOT MUCH DIFFERENT BETWEEN RA AND OA, BUT 523 LOW-METHYLATED REGIONS (LMRS) WERE SPECIFIC TO RA. THE LMRS WERE PREFERENTIALLY LOCALIZED AT THE 5' INTRONS AND OVERLAPPED WITH TRANSCRIPTION FACTOR BINDING MOTIFS FOR GLI1, RUNX2, AND TFAP2A/C. SINGLE BASE-SCALE DIFFERENTIALLY METHYLATED CPGS WERE LINKED WITH SEVERAL NETWORKS RELATED TO WOUND RESPONSE, TISSUE DEVELOPMENT, COLLAGEN FIBRIL ORGANIZATION, AND THE TGF-BETA RECEPTOR SIGNALING PATHWAY. FURTHER, THE DNA METHYLATION OF 201 CPGS WAS SIGNIFICANTLY CORRELATED WITH 27 EXPRESSED MIRNA GENES. OUR INTERPRETATION OF EPIGENOMIC DATA OF THE SYNOVIOCYTES FROM RA AND OA PATIENTS IS AN INFORMATIVE RESOURCE TO FURTHER INVESTIGATE REGULATORY ELEMENTS AND BIOMARKERS RESPONSIBLE FOR THE PATHOPHYSIOLOGY OF RA AND OA. 2019 17 1218 28 CRISPR INTERFERENCE OF A CLONALLY VARIANT GC-RICH NONCODING RNA FAMILY LEADS TO GENERAL REPRESSION OF VAR GENES IN PLASMODIUM FALCIPARUM. THE HUMAN MALARIA PARASITE PLASMODIUM FALCIPARUM USES MUTUALLY EXCLUSIVE EXPRESSION OF THE PFEMP1-ENCODING VAR GENE FAMILY TO EVADE THE HOST IMMUNE SYSTEM. DESPITE PROGRESS IN THE MOLECULAR UNDERSTANDING OF THE DEFAULT SILENCING MECHANISM, THE ACTIVATION MECHANISM OF THE UNIQUELY EXPRESSED VAR MEMBER REMAINS ELUSIVE. A GC-RICH NONCODING RNA (NCRNA) GENE FAMILY HAS COEVOLVED WITH PLASMODIUM SPECIES THAT EXPRESS VAR GENES. HERE, WE SHOW THAT THIS NCRNA FAMILY IS TRANSCRIBED IN A CLONALLY VARIANT MANNER, WITH PREDOMINANT TRANSCRIPTION OF A SINGLE MEMBER OCCURRING WHEN THE NCRNA IS LOCATED ADJACENT TO AND UPSTREAM OF AN ACTIVE VAR GENE. WE DEVELOPED A SPECIFIC CRISPR INTERFERENCE (CRISPRI) STRATEGY THAT ALLOWED FOR THE TRANSCRIPTIONAL REPRESSION OF ALL GC-RICH MEMBERS. A LACK OF GC-RICH NCRNA TRANSCRIPTION LED TO THE DOWNREGULATION OF THE ENTIRE VAR GENE FAMILY IN RING-STAGE PARASITES. STRIKINGLY, IN MATURE BLOOD-STAGE PARASITES, THE GC-RICH NCRNA CRISPRI AFFECTED THE TRANSCRIPTION PATTERNS OF OTHER CLONALLY VARIANT GENE FAMILIES, INCLUDING THE DOWNREGULATION OF ALL PFMC-2TM MEMBERS. WE PROVIDE EVIDENCE FOR THE KEY ROLE OF GC-RICH NCRNA TRANSCRIPTION IN VAR GENE ACTIVATION AND DISCOVERED A MOLECULAR LINK BETWEEN THE TRANSCRIPTIONAL CONTROL OF VARIOUS CLONALLY VARIANT MULTIGENE FAMILIES INVOLVED IN PARASITE VIRULENCE. THIS WORK OPENS NEW AVENUES FOR ELUCIDATING THE MOLECULAR PROCESSES THAT CONTROL IMMUNE EVASION AND PATHOGENESIS IN P. FALCIPARUMIMPORTANCEPLASMODIUM FALCIPARUM IS THE DEADLIEST MALARIA PARASITE SPECIES, ACCOUNTING FOR THE VAST MAJORITY OF DISEASE CASES AND DEATHS. THE VIRULENCE OF THIS PARASITE IS RELIANT UPON THE MUTUALLY EXCLUSIVE EXPRESSION OF CYTOADHERENCE PROTEINS ENCODED BY THE 60-MEMBER VAR GENE FAMILY. ANTIGENIC VARIATION OF THIS MULTIGENE FAMILY SERVES AS AN IMMUNE EVASION MECHANISM, ULTIMATELY LEADING TO CHRONIC INFECTION AND PATHOGENESIS. UNDERSTANDING THE REGULATION MECHANISM OF ANTIGENIC VARIATION IS KEY TO DEVELOPING NEW THERAPEUTIC AND CONTROL STRATEGIES. OUR STUDY UNCOVERS A NOVEL LAYER IN THE EPIGENETIC REGULATION OF TRANSCRIPTION OF THIS FAMILY OF VIRULENCE GENES BY MEANS OF A MULTIGENE-TARGETING CRISPR INTERFERENCE APPROACH. 2020 18 408 30 ANALYSIS OF GENE EXPRESSION AND METHYLATION DATASETS IDENTIFIED ADAMTS9, FKBP5, AND PFKBF3 AS BIOMARKERS FOR OSTEOARTHRITIS. BACKGROUND: OSTEOARTHRITIS (OA) IS A KIND OF CHRONIC OSTEOARTHROPATHY AND DEGENERATIVE JOINT DISEASE. EPIGENETIC REGULATION IN THE GENE EXPRESSION DYNAMICS HAS BECOME INCREASINGLY IMPORTANT IN OA. WE PERFORMED A COMBINED ANALYSIS OF TWO TYPES OF MICROARRAY DATASETS (GENE EXPRESSION AND DNA METHYLATION) TO IDENTIFY METHYLATION-BASED KEY BIOMARKERS TO PROVIDE A BETTER UNDERSTANDING OF MOLECULAR BIOLOGICAL MECHANISMS OF OA. METHODS: WE OBTAINED TWO EXPRESSION PROFILING DATASETS (GSE55235, GSE55457) AND ONE DNA METHYLATION PROFILING DATA SET (GSE63695) FROM THE GENE EXPRESSION OMNIBUS. FIRST, DIFFERENTIALLY EXPRESSED GENES (DEGS) BETWEEN PATIENTS WITH OA AND CONTROLS WERE IDENTIFIED USING THE LIMMA PACKAGE IN R(V3.4.4). THEN, FUNCTION ENRICHMENT ANALYSIS OF DEGS WAS PERFORMED USING A DAVID DATABASE. FOR DNA METHYLATION DATASETS, CHAMP METHYLATION ANALYSIS PACKAGE WAS USED TO IDENTIFY DIFFERENTIAL METHYLATION GENES (DMGS). FINALLY, A COMPREHENSIVE ANALYSIS OF DEGS AND DMGS WAS CONDUCTED TO IDENTIFY GENES THAT EXHIBITED DIFFERENTIAL EXPRESSION AND METHYLATION SIMULTANEOUSLY. RESULTS: WE IDENTIFIED 112 DEGS AND 2,896 DMGS IN PATIENTS WITH OA COMPARED WITH CONTROLS. FUNCTIONAL ANALYSIS OF DEGS OBTAINED THAT INFLAMMATORY RESPONSES, IMMUNE RESPONSES, AND POSITIVE REGULATION OF APOPTOSIS, TUMOR NECROSIS FACTOR (TNF) SIGNALING PATHWAY, AND OSTEOCLAST DIFFERENTIATION MAY BE INVOLVED IN THE PATHOGENESIS OF OA. CROSS-ANALYSIS REVEALED 26 GENES THAT EXHIBITED DIFFERENTIAL EXPRESSION AND METHYLATION IN OA. AMONG THEM, ADAMTS9, FKBP5, AND PFKBF3 WERE IDENTIFIED AS VALUABLE METHYLATION-BASED BIOMARKERS FOR OA. CONCLUSION: IN SUMMARY, OUR STUDY IDENTIFIED DIFFERENT MOLECULAR FEATURES BETWEEN PATIENTS WITH OA AND CONTROLS. THIS MAY PROVIDE NEW CLUES FOR CLARIFYING THE PATHOGENETIC MECHANISMS OF OA. 2019 19 1727 42 DYSREGULATION OF LONG NON-CODING RNAS IN MOUSE MODELS OF LOCALIZATION-RELATED EPILEPSY. GENOME-WIDE PROFILING HAS REVEALED THAT EUKARYOTIC GENOMES ARE TRANSCRIBED INTO NUMEROUS NON-CODING RNAS. IN PARTICULAR, LONG NON-CODING RNAS (LNCRNAS) HAVE BEEN IMPLICATED IN VARIOUS HUMAN DISEASES DUE TO THEIR BIOCHEMICAL AND FUNCTIONAL DIVERSITY. EPILEPTIC DISORDERS HAVE BEEN CHARACTERIZED BY DYSREGULATION OF EPIGENETIC REGULATORY MECHANISMS, AND RECENT STUDIES HAVE IDENTIFIED SEVERAL LNCRNAS INVOLVED IN NEURAL DEVELOPMENT AND NETWORK FUNCTION. HOWEVER, COMPREHENSIVE PROFILING OF LNCRNAS IMPLICATED IN CHRONIC EPILEPSY HAS BEEN LACKING. IN THIS STUDY, MICROARRAY ANALYSIS WAS PERFORMED TO OBTAIN THE EXPRESSION PROFILE OF LNCRNAS DYSREGULATED IN PILOCARPINE AND KAINATE MODELS, TWO MODELS OF TEMPORAL LOBE EPILEPSY COMMONLY USED FOR STUDYING EPILEPTIC MECHANISMS. TOTAL OF 4622 LNCRNAS WERE ANALYZED: 384 LNCRNAS WERE SIGNIFICANTLY DYSREGULATED IN PILOCARPINE MODEL, AND 279 LNCRNAS WERE SIGNIFICANTLY DYSREGULATED IN KAINATE MODEL COMPARED WITH CONTROL MICE (>/=3.0-FOLD, P < 0.05). AMONG THESE, 54 AND 14 LNCRNAS, RESPECTIVELY, HAD ADJACENT PROTEIN-CODING GENES WHOSE EXPRESSIONS WERE ALSO SIGNIFICANTLY DYSREGULATED (>/=2.0-FOLD, P < 0.05). MAJORITY OF THESE PAIRS OF LNCRNAS AND ADJACENT GENES SHARED THE SAME DIRECTION OF DYSREGULATION. FOR THE SELECTED ADJACENT GENE-LNCRNA PAIRS, SIGNIFICANT GENE ONTOLOGY TERMS WERE EMBRYONIC APPENDAGE MORPHOGENESIS AND NEURON DIFFERENTIATION. THIS WAS THE FIRST STUDY TO COMPREHENSIVELY IDENTIFY DYSREGULATED LNCRNAS IN TWO DIFFERENT MODELS OF CHRONIC EPILEPSY AND WILL LIKELY PROVIDE A NOVEL INSIGHT INTO DEVELOPING LNCRNA THERAPEUTICS. 2015 20 17 25 5' FLANKING REGION OF VAR GENES NUCLEATE HISTONE MODIFICATION PATTERNS LINKED TO PHENOTYPIC INHERITANCE OF VIRULENCE TRAITS IN MALARIA PARASITES. IN THE HUMAN MALARIA PARASITE PLASMODIUM FALCIPARUM ANTIGENIC VARIATION FACILITATES LONG-TERM CHRONIC INFECTION OF THE HOST. THIS IS ACHIEVED BY SEQUENTIAL EXPRESSION OF A SINGLE MEMBER OF THE 60-MEMBER VAR FAMILY. HERE WE SHOW THAT THE 5' FLANKING REGION NUCLEATES EPIGENETIC EVENTS STRONGLY LINKED TO THE MAINTENANCE OF MONO-ALLELIC VAR GENE EXPRESSION PATTERN DURING PARASITE PROLIFERATION. TRI- AND DIMETHYLATION OF HISTONE H3 LYSINE 4 PEAK IN THE 5' UPSTREAM REGION OF TRANSCRIBED VAR AND DURING THE POISED STATE (NON-TRANSCRIBED PHASE OF VAR GENES DURING THE 48 H ASEXUAL LIFE CYCLE), 'BOOKMARKING' THIS MEMBER FOR RE-ACTIVATION AT THE ONSET OF THE NEXT CYCLE. HISTONE H3 LYSINE 9 TRIMETHYLATION ACTS AS AN ANTAGONIST TO LYSINE 4 METHYLATION TO ESTABLISH STABLY SILENT VAR GENE STATES ALONG THE 5' FLANKING AND CODING REGION. FURTHERMORE, WE SHOW THAT COMPETITION EXISTS BETWEEN H3K9 METHYLATION AND H3K9 ACETYLATION IN THE 5' FLANKING REGION AND THAT THESE MARKS CONTRIBUTE EPIGENETICALLY TO REPRESSING OR ACTIVATING VAR GENE EXPRESSION. OUR WORK POINTS TO A PIVOTAL ROLE OF THE HISTONE METHYL MARK WRITING AND READING MACHINERY IN THE PHENOTYPIC INHERITANCE OF VIRULENCE TRAITS IN THE MALARIA PARASITE. 2007