Differential recruitment of coregulators to the RORA promoter adds another layer of complexity to gene (dys) regulation by sex hormones in autism / Tewarit SARACHANA in Molecular Autism, (October 2013)  

Public ISBD [article]  inMolecular Autism > (October 2013) Titre : Differential recruitment of coregulators to the RORA promoter adds another layer of complexity to gene (dys) regulation by sex hormones in autism Type de document : Texte imprimé et/ou numérique Auteurs : Tewarit SARACHANA, Auteur ; Valerie HU, Auteur Langues : Anglais (eng) Index. décimale : PER Périodiques Résumé : Our independent cohort studies have consistently shown the reduction of the nuclear receptor RORA (retinoic acid-related orphan receptor-alpha) in lymphoblasts as well as in brain tissues from individuals with autism spectrum disorder (ASD). Moreover, we have found that RORA regulates the gene for aromatase, which converts androgen to estrogen, and that male and female hormones regulate RORA in opposite directions, with androgen suppressing RORA, suggesting that the sexually dimorphic regulation of RORA may contribute to the male bias in ASD. However, the molecular mechanisms through which androgen and estrogen differentially regulate RORA are still unknown. Here we use functional knockdown of hormone receptors and coregulators with small interfering RNA (siRNA) to investigate their involvement in sex hormone regulation of RORA in human neuronal cells. Luciferase assays using a vector containing various RORA promoter constructs were first performed to identify the promoter regions required for inverse regulation of RORA by male and female hormones. Sequential chromatin immunoprecipitation methods followed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses of RORA expression in hormone-treated SH-SY5Y cells were then utilized to identify coregulators that associate with hormone receptors on the RORA promoter. siRNA-mediated knockdown of interacting coregulators was performed followed by qRT-PCR analyses to confirm the functional requirement of each coregulator in hormone-regulated RORA expression. Our studies demonstrate the direct involvement of androgen receptor (AR) and estrogen receptor (ER) in the regulation of RORA by male and female hormones, respectively, and that the promoter region between 10055 bp and 2344 bp from the transcription start site of RORA is required for the inverse hormonal regulation. We further show that AR interacts with SUMO1, a reported suppressor of AR transcriptional activity, whereas ERalpha interacts with the coactivator NCOA5 on the RORA promoter. siRNA-mediated knockdown of SUMO1 and NCOA5 attenuate the sex hormone effects on RORA expression. AR and SUMO1 are involved in the suppression RORA expression by androgen, while ERalpha and NCOA5 collaborate in the up-regulation of RORA by estrogen. While this study offers a better understanding of molecular mechanisms involved in sex hormone regulation of RORA, it also reveals another layer of complexity with regard to gene regulation in ASD. Inasmuch as coregulators are capable of interacting with a multitude of transcription factors, aberrant expression of coregulator proteins, as we have seen previously in lymphoblasts from individuals with ASD, may contribute to the polygenic nature of gene dysregulation in ASD. En ligne : http://dx.doi.org/10.1186/2040-2392-4-39 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=227 [article] Differential recruitment of coregulators to the RORA promoter adds another layer of complexity to gene (dys) regulation by sex hormones in autism [Texte imprimé et/ou numérique] / Tewarit SARACHANA, Auteur ; Valerie HU, Auteur. Langues : Anglais (eng) in Molecular Autism > (October 2013) Index. décimale : PER Périodiques Résumé : Our independent cohort studies have consistently shown the reduction of the nuclear receptor RORA (retinoic acid-related orphan receptor-alpha) in lymphoblasts as well as in brain tissues from individuals with autism spectrum disorder (ASD). Moreover, we have found that RORA regulates the gene for aromatase, which converts androgen to estrogen, and that male and female hormones regulate RORA in opposite directions, with androgen suppressing RORA, suggesting that the sexually dimorphic regulation of RORA may contribute to the male bias in ASD. However, the molecular mechanisms through which androgen and estrogen differentially regulate RORA are still unknown. Here we use functional knockdown of hormone receptors and coregulators with small interfering RNA (siRNA) to investigate their involvement in sex hormone regulation of RORA in human neuronal cells. Luciferase assays using a vector containing various RORA promoter constructs were first performed to identify the promoter regions required for inverse regulation of RORA by male and female hormones. Sequential chromatin immunoprecipitation methods followed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses of RORA expression in hormone-treated SH-SY5Y cells were then utilized to identify coregulators that associate with hormone receptors on the RORA promoter. siRNA-mediated knockdown of interacting coregulators was performed followed by qRT-PCR analyses to confirm the functional requirement of each coregulator in hormone-regulated RORA expression. Our studies demonstrate the direct involvement of androgen receptor (AR) and estrogen receptor (ER) in the regulation of RORA by male and female hormones, respectively, and that the promoter region between 10055 bp and 2344 bp from the transcription start site of RORA is required for the inverse hormonal regulation. We further show that AR interacts with SUMO1, a reported suppressor of AR transcriptional activity, whereas ERalpha interacts with the coactivator NCOA5 on the RORA promoter. siRNA-mediated knockdown of SUMO1 and NCOA5 attenuate the sex hormone effects on RORA expression. AR and SUMO1 are involved in the suppression RORA expression by androgen, while ERalpha and NCOA5 collaborate in the up-regulation of RORA by estrogen. While this study offers a better understanding of molecular mechanisms involved in sex hormone regulation of RORA, it also reveals another layer of complexity with regard to gene regulation in ASD. Inasmuch as coregulators are capable of interacting with a multitude of transcription factors, aberrant expression of coregulator proteins, as we have seen previously in lymphoblasts from individuals with ASD, may contribute to the polygenic nature of gene dysregulation in ASD. En ligne : http://dx.doi.org/10.1186/2040-2392-4-39 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=227

Gene expression profiling differentiates autism case-controls and phenotypic variants of autism spectrum disorders: evidence for circadian rhythm dysfunction in severe autism / Valerie W. HU in Autism Research, 2-2 (April 2009)  

Public ISBD [article]  inAutism Research > 2-2 (April 2009) . - p.78-97 Titre : Gene expression profiling differentiates autism case-controls and phenotypic variants of autism spectrum disorders: evidence for circadian rhythm dysfunction in severe autism Type de document : Texte imprimé et/ou numérique Auteurs : Valerie W. HU, Auteur ; Mara E. STEINBERG, Auteur ; Tewarit SARACHANA, Auteur ; Kyung Soon KIM, Auteur ; AnhThu NGUYEN, Auteur ; Shreya KULKARNI, Auteur ; Truong LUU, Auteur ; Yinglei LAI, Auteur ; Norman H. LEE, Auteur Année de publication : 2009 Article en page(s) : p.78-97 Langues : Anglais (eng) Mots-clés : autism-phenotypes gene-expression-profiling circadian-rhythm novel-genes Index. décimale : PER Périodiques Résumé : Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by delayed/abnormal language development, deficits in social interaction, repetitive behaviors and restricted interests. The heterogeneity in clinical presentation of ASD, likely due to different etiologies, complicates genetic/biological analyses of these disorders. DNA microarray analyses were conducted on 116 lymphoblastoid cell lines (LCL) from individuals with idiopathic autism who are divided into three phenotypic subgroups according to severity scores from the commonly used Autism Diagnostic Interview-Revised questionnaire and age-matched, nonautistic controls. Statistical analyses of gene expression data from control LCL against that of LCL from ASD probands identify genes for which expression levels are either quantitatively or qualitatively associated with phenotypic severity. Comparison of the significant differentially expressed genes from each subgroup relative to the control group reveals differentially expressed genes unique to each subgroup as well as genes in common across subgroups. Among the findings unique to the most severely affected ASD group are 15 genes that regulate circadian rhythm, which has been shown to have multiple effects on neurological as well as metabolic functions commonly dysregulated in autism. Among the genes common to all three subgroups of ASD are 20 novel genes mostly in putative noncoding regions, which appear to associate with androgen sensitivity and which may underlie the strong 4:1 bias toward affected males. En ligne : http://dx.doi.org/10.1002/aur.73 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=936 [article] Gene expression profiling differentiates autism case-controls and phenotypic variants of autism spectrum disorders: evidence for circadian rhythm dysfunction in severe autism [Texte imprimé et/ou numérique] / Valerie W. HU, Auteur ; Mara E. STEINBERG, Auteur ; Tewarit SARACHANA, Auteur ; Kyung Soon KIM, Auteur ; AnhThu NGUYEN, Auteur ; Shreya KULKARNI, Auteur ; Truong LUU, Auteur ; Yinglei LAI, Auteur ; Norman H. LEE, Auteur . - 2009 . - p.78-97. Langues : Anglais (eng) in Autism Research > 2-2 (April 2009) . - p.78-97 Mots-clés : autism-phenotypes gene-expression-profiling circadian-rhythm novel-genes Index. décimale : PER Périodiques Résumé : Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by delayed/abnormal language development, deficits in social interaction, repetitive behaviors and restricted interests. The heterogeneity in clinical presentation of ASD, likely due to different etiologies, complicates genetic/biological analyses of these disorders. DNA microarray analyses were conducted on 116 lymphoblastoid cell lines (LCL) from individuals with idiopathic autism who are divided into three phenotypic subgroups according to severity scores from the commonly used Autism Diagnostic Interview-Revised questionnaire and age-matched, nonautistic controls. Statistical analyses of gene expression data from control LCL against that of LCL from ASD probands identify genes for which expression levels are either quantitatively or qualitatively associated with phenotypic severity. Comparison of the significant differentially expressed genes from each subgroup relative to the control group reveals differentially expressed genes unique to each subgroup as well as genes in common across subgroups. Among the findings unique to the most severely affected ASD group are 15 genes that regulate circadian rhythm, which has been shown to have multiple effects on neurological as well as metabolic functions commonly dysregulated in autism. Among the genes common to all three subgroups of ASD are 20 novel genes mostly in putative noncoding regions, which appear to associate with androgen sensitivity and which may underlie the strong 4:1 bias toward affected males. En ligne : http://dx.doi.org/10.1002/aur.73 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=936

Genome-wide identification of transcriptional targets of RORA reveals direct regulation of multiple genes associated with autism spectrum disorder / Tewarit SARACHANA in Molecular Autism, (May 2013)  

Public ISBD [article]  inMolecular Autism > (May 2013) . - 19 p. Titre : Genome-wide identification of transcriptional targets of RORA reveals direct regulation of multiple genes associated with autism spectrum disorder Type de document : Texte imprimé et/ou numérique Auteurs : Tewarit SARACHANA, Auteur ; Valerie W. HU, Auteur Année de publication : 2013 Article en page(s) : 19 p. Langues : Anglais (eng) Mots-clés : RORA  Autism  Nuclear hormone receptor  Transcriptional targets  Chromatin immunoprecipitation  Promoter microarray Index. décimale : PER Périodiques Résumé : BACKGROUND:We have recently identified the nuclear hormone receptor RORA (retinoic acid-related orphan receptor-alpha) as a novel candidate gene for autism spectrum disorder (ASD). Our independent cohort studies have consistently demonstrated the reduction of RORA transcript and/or protein levels in blood-derived lymphoblasts as well as in the postmortem prefrontal cortex and cerebellum of individuals with ASD. Moreover, we have also shown that RORA has the potential to be under negative and positive regulation by androgen and estrogen, respectively, suggesting the possibility that RORA may contribute to the male bias of ASD. However, little is known about transcriptional targets of this nuclear receptor, particularly in humans.METHODS:Here we identify transcriptional targets of RORA in human neuronal cells on a genome-wide level using chromatin immunoprecipitation (ChIP) with an anti-RORA antibody followed by whole-genome promoter array (chip) analysis. Selected potential targets of RORA were then validated by an independent ChIP followed by quantitative PCR analysis. To further demonstrate that reduced RORA expression results in reduced transcription of RORA targets, we determined the expression levels of the selected transcriptional targets in RORA-deficient human neuronal cells, as well as in postmortem brain tissues from individuals with ASD who exhibit reduced RORA expression.RESULTS:The ChIP-on-chip analysis reveals that RORA1, a major isoform of RORA protein in human brain, can be recruited to as many as 2,764 genomic locations corresponding to promoter regions of 2,544 genes across the human genome. Gene ontology analysis of this dataset of genes that are potentially directly regulated by RORA1 reveals statistically significant enrichment in biological functions negatively impacted in individuals with ASD, including neuronal differentiation, adhesion and survival, synaptogenesis, synaptic transmission and plasticity, and axonogenesis, as well as higher level functions such as development of the cortex and cerebellum, cognition, memory, and spatial learning. Independent ChIP-quantitative PCR analyses confirm binding of RORA1 to promoter regions of selected ASD-associated genes, including A2BP1, CYP19A1, ITPR1, NLGN1, and NTRK2, whose expression levels (in addition to HSD17B10) are also decreased in RORA1-repressed human neuronal cells and in prefrontal cortex tissues from individuals with ASD.CONCLUSIONS:Findings from this study indicate that RORA transcriptionally regulates A2BP1, CYP19A1, HSD17B10, ITPR1, NLGN1, and NTRK2, and strongly suggest that reduction of this sex hormone-sensitive nuclear receptor in the brain causes dysregulated expression of these ASD-relevant genes as well as their associated pathways and functions which, in turn, may contribute to the underlying pathobiology of ASD. En ligne : http://dx.doi.org/10.1186/2040-2392-4-14 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202 [article] Genome-wide identification of transcriptional targets of RORA reveals direct regulation of multiple genes associated with autism spectrum disorder [Texte imprimé et/ou numérique] / Tewarit SARACHANA, Auteur ; Valerie W. HU, Auteur . - 2013 . - 19 p. Langues : Anglais (eng) in Molecular Autism > (May 2013) . - 19 p. Mots-clés : RORA  Autism  Nuclear hormone receptor  Transcriptional targets  Chromatin immunoprecipitation  Promoter microarray Index. décimale : PER Périodiques Résumé : BACKGROUND:We have recently identified the nuclear hormone receptor RORA (retinoic acid-related orphan receptor-alpha) as a novel candidate gene for autism spectrum disorder (ASD). Our independent cohort studies have consistently demonstrated the reduction of RORA transcript and/or protein levels in blood-derived lymphoblasts as well as in the postmortem prefrontal cortex and cerebellum of individuals with ASD. Moreover, we have also shown that RORA has the potential to be under negative and positive regulation by androgen and estrogen, respectively, suggesting the possibility that RORA may contribute to the male bias of ASD. However, little is known about transcriptional targets of this nuclear receptor, particularly in humans.METHODS:Here we identify transcriptional targets of RORA in human neuronal cells on a genome-wide level using chromatin immunoprecipitation (ChIP) with an anti-RORA antibody followed by whole-genome promoter array (chip) analysis. Selected potential targets of RORA were then validated by an independent ChIP followed by quantitative PCR analysis. To further demonstrate that reduced RORA expression results in reduced transcription of RORA targets, we determined the expression levels of the selected transcriptional targets in RORA-deficient human neuronal cells, as well as in postmortem brain tissues from individuals with ASD who exhibit reduced RORA expression.RESULTS:The ChIP-on-chip analysis reveals that RORA1, a major isoform of RORA protein in human brain, can be recruited to as many as 2,764 genomic locations corresponding to promoter regions of 2,544 genes across the human genome. Gene ontology analysis of this dataset of genes that are potentially directly regulated by RORA1 reveals statistically significant enrichment in biological functions negatively impacted in individuals with ASD, including neuronal differentiation, adhesion and survival, synaptogenesis, synaptic transmission and plasticity, and axonogenesis, as well as higher level functions such as development of the cortex and cerebellum, cognition, memory, and spatial learning. Independent ChIP-quantitative PCR analyses confirm binding of RORA1 to promoter regions of selected ASD-associated genes, including A2BP1, CYP19A1, ITPR1, NLGN1, and NTRK2, whose expression levels (in addition to HSD17B10) are also decreased in RORA1-repressed human neuronal cells and in prefrontal cortex tissues from individuals with ASD.CONCLUSIONS:Findings from this study indicate that RORA transcriptionally regulates A2BP1, CYP19A1, HSD17B10, ITPR1, NLGN1, and NTRK2, and strongly suggest that reduction of this sex hormone-sensitive nuclear receptor in the brain causes dysregulated expression of these ASD-relevant genes as well as their associated pathways and functions which, in turn, may contribute to the underlying pathobiology of ASD. En ligne : http://dx.doi.org/10.1186/2040-2392-4-14 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=202

Investigation of sex differences in the expression of RORA and its transcriptional targets in the brain as a potential contributor to the sex bias in autism / Valerie W. HU in Molecular Autism, (May 2015)  

Public ISBD [article]  inMolecular Autism > (May 2015) . - p.1-19 Titre : Investigation of sex differences in the expression of RORA and its transcriptional targets in the brain as a potential contributor to the sex bias in autism Type de document : Texte imprimé et/ou numérique Auteurs : Valerie W. HU, Auteur ; Tewarit SARACHANA, Auteur ; Rachel M. SHERRARD, Auteur ; Kristen M. KOCHER, Auteur Article en page(s) : p.1-19 Langues : Anglais (eng) Index. décimale : PER Périodiques Résumé : Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by significant impairment in reciprocal social interactions and communication coupled with stereotyped, repetitive behaviors and restricted interests. Although genomic and functional studies are beginning to reveal some of the genetic complexity and underlying pathobiology of ASD, the consistently reported male bias of ASD remains an enigma. We have recently proposed that retinoic acid-related orphan receptor alpha (RORA), which is reduced in the brain and lymphoblastoid cell lines of multiple cohorts of individuals with ASD and oppositely regulated by male and female hormones, might contribute to the sex bias in autism by differentially regulating target genes, including CYP19A1 (aromatase), in a sex-dependent manner that can also lead to elevated testosterone levels, a proposed risk factor for autism. En ligne : http://dx.doi.org/10.1186/2040-2392-6-7 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=277 [article] Investigation of sex differences in the expression of RORA and its transcriptional targets in the brain as a potential contributor to the sex bias in autism [Texte imprimé et/ou numérique] / Valerie W. HU, Auteur ; Tewarit SARACHANA, Auteur ; Rachel M. SHERRARD, Auteur ; Kristen M. KOCHER, Auteur . - p.1-19. Langues : Anglais (eng) in Molecular Autism > (May 2015) . - p.1-19 Index. décimale : PER Périodiques Résumé : Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by significant impairment in reciprocal social interactions and communication coupled with stereotyped, repetitive behaviors and restricted interests. Although genomic and functional studies are beginning to reveal some of the genetic complexity and underlying pathobiology of ASD, the consistently reported male bias of ASD remains an enigma. We have recently proposed that retinoic acid-related orphan receptor alpha (RORA), which is reduced in the brain and lymphoblastoid cell lines of multiple cohorts of individuals with ASD and oppositely regulated by male and female hormones, might contribute to the sex bias in autism by differentially regulating target genes, including CYP19A1 (aromatase), in a sex-dependent manner that can also lead to elevated testosterone levels, a proposed risk factor for autism. En ligne : http://dx.doi.org/10.1186/2040-2392-6-7 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=277

---

1 (1 - 4 / 4)