1Proc. Natl. Acad. Sci. U.S.A. 2007 Feb 104: 2815-20
PMID17360599
TitleGenetic analysis of the calcineurin pathway identifies members of the EGR gene family, specifically EGR3, as potential susceptibility candidates in schizophrenia.
AbstractThe calcineurin cascade is central to neuronal signal transduction, and genes in this network are intriguing candidate schizophrenia susceptibility genes. To replicate and extend our previously reported association between the PPP3CC gene, encoding the calcineurin catalytic gamma-subunit, and schizophrenia, we examined 84 SNPs from 14 calcineurin-related candidate genes for genetic association by using 124 Japanese schizophrenic pedigrees. Four of these genes (PPP3CC, EGR2, EGR3, and EGR4) showed nominally significant association with schizophrenia. In a postmortem brain study, EGR1, EGR2, and EGR3 transcripts were shown to be down-regulated in the prefrontal cortex of schizophrenic, but not bipolar, patients. These findings raise a potentially important role for EGR genes in schizophrenia pathogenesis. Because EGR3 is an attractive candidate gene based on its chromosomal location close to PPP3CC within 8p21.3 and its functional link to dopamine, glutamate, and neuregulin signaling, we extended our analysis by resequencing the entire EGR3 genomic interval and detected 15 SNPs. One of these, IVS1 + 607A-->G SNP, displayed the strongest evidence for disease association, which was confirmed in 1,140 independent case-control samples. An in vitro promoter assay detected a possible expression-regulatory effect of this SNP. These findings support the previous genetic association of altered calcineurin signaling with schizophrenia pathogenesis and identify EGR3 as a compelling susceptibility gene.
SCZ Keywordsschizophrenia, schizophrenic
2Proc. Natl. Acad. Sci. U.S.A. 2007 Feb 104: 2815-20
PMID17360599
TitleGenetic analysis of the calcineurin pathway identifies members of the EGR gene family, specifically EGR3, as potential susceptibility candidates in schizophrenia.
AbstractThe calcineurin cascade is central to neuronal signal transduction, and genes in this network are intriguing candidate schizophrenia susceptibility genes. To replicate and extend our previously reported association between the PPP3CC gene, encoding the calcineurin catalytic gamma-subunit, and schizophrenia, we examined 84 SNPs from 14 calcineurin-related candidate genes for genetic association by using 124 Japanese schizophrenic pedigrees. Four of these genes (PPP3CC, EGR2, EGR3, and EGR4) showed nominally significant association with schizophrenia. In a postmortem brain study, EGR1, EGR2, and EGR3 transcripts were shown to be down-regulated in the prefrontal cortex of schizophrenic, but not bipolar, patients. These findings raise a potentially important role for EGR genes in schizophrenia pathogenesis. Because EGR3 is an attractive candidate gene based on its chromosomal location close to PPP3CC within 8p21.3 and its functional link to dopamine, glutamate, and neuregulin signaling, we extended our analysis by resequencing the entire EGR3 genomic interval and detected 15 SNPs. One of these, IVS1 + 607A-->G SNP, displayed the strongest evidence for disease association, which was confirmed in 1,140 independent case-control samples. An in vitro promoter assay detected a possible expression-regulatory effect of this SNP. These findings support the previous genetic association of altered calcineurin signaling with schizophrenia pathogenesis and identify EGR3 as a compelling susceptibility gene.
SCZ Keywordsschizophrenia, schizophrenic
3Prog. Neuropsychopharmacol. Biol. Psychiatry 2010 Apr 34: 506-9
PMID20144677
TitleNo association between EGR gene family polymorphisms and schizophrenia in the Chinese population.
AbstractEarly growth response (EGR) genes are thought to have a role in the pathogenesis of schizophrenia because of their conserved DNA binding domain and biologically activity in neuronal plasticity. This zinc-finger motif could influence gene post-translational modification and expression. The multigenetic association model, using markers in genes of similar or antagonistic biological effects within a signal pathway or gene family, might be more appropriate to this aspect of the schizophrenia hypothesis than the single gene strategy. In this study we investigated the role of EGR1, EGR2, EGR3 and EGR4 within the EGR family. Taqman technology was used to examine 12 single nucleotide polymorphisms (SNPs) covering these four genes in 2044 Chinese Han subjects. Case-control analyses were performed to detect association of these 4 genes with schizophrenia and multifactor dimensionality reduction (MDR) analysis was employed to examine their potential gene-gene interaction in schizophrenia. Neither allelic nor genotypic single-locus tests revealed any significant association between EGR1-4 and the risk of schizophrenia nor was any such association found with regard to interaction within EGR1-4 (p(min)=0.623, CV Consistency=10/10). We concluded that although multiple candidate genes are involved in schizophrenogenic development, the EGR family may not play a major role in schizophrenia susceptibility in the Chinese Han population.
SCZ Keywordsschizophrenia, schizophrenic
4Am. J. Med. Genet. B Neuropsychiatr. Genet. 2010 Oct 153B: 1355-60
PMID20687139
TitleEGR3 as a potential susceptibility gene for schizophrenia in Korea.
AbstractEarly growth response (EGR) genes play critical roles in signal transduction in the brain, which is involved in neuronal activation, brain development, and synaptic plasticity. EGR genes, including EGR2, EGR3, and EGR4, showed significant association with schizophrenia in Japanese schizophrenic pedigrees. In particular, EGR3, which resides at the chromosomal location 8p21.3, was suggested to be a potential susceptibility gene in schizophrenia based on a study of Japanese cases. However, this requires further replication with an independent sample set. We investigated the association of the EGR3 and EGR2 genes, which were suggested as potential susceptibility genes for schizophrenia supported by both genetic association and postmortem brain expression studies, with schizophrenia in Korean patients. Along with 350 healthy individuals, 244 schizophrenic patients were analyzed. Among the four examined single-nucleotide polymorphisms (SNPs) of EGR3 (rs1008949, rs7009708, rs35201266, and rs3750192), SNP rs35201266 in intron 1 of the EGR3 gene showed a significant association with schizophrenia (P?=?0.0008, ?(2)?=?11.156, OR?=?1.493), which withstands multiple testing correction. In addition, the "T-G-C-G" haplotype of EGR3 was under-represented in the patients with schizophrenia (P?=?0.0073, ?(2)?=?7.188, OR?=?0.697). However, an association between the SNPs of EGR2 (rs2295814 and rs2297488) and schizophrenia was not found. These findings are consistent with the previous genetic association of the EGR3 gene in Japanese cohorts, which is the first replication concerning the association of EGR3 with schizophrenia in an independent cohort. Taken together, EGR3 could be suggested as a compelling susceptibility gene in schizophrenia.
SCZ Keywordsschizophrenia, schizophrenic
5Am. J. Med. Genet. B Neuropsychiatr. Genet. 2010 Oct 153B: 1355-60
PMID20687139
TitleEGR3 as a potential susceptibility gene for schizophrenia in Korea.
AbstractEarly growth response (EGR) genes play critical roles in signal transduction in the brain, which is involved in neuronal activation, brain development, and synaptic plasticity. EGR genes, including EGR2, EGR3, and EGR4, showed significant association with schizophrenia in Japanese schizophrenic pedigrees. In particular, EGR3, which resides at the chromosomal location 8p21.3, was suggested to be a potential susceptibility gene in schizophrenia based on a study of Japanese cases. However, this requires further replication with an independent sample set. We investigated the association of the EGR3 and EGR2 genes, which were suggested as potential susceptibility genes for schizophrenia supported by both genetic association and postmortem brain expression studies, with schizophrenia in Korean patients. Along with 350 healthy individuals, 244 schizophrenic patients were analyzed. Among the four examined single-nucleotide polymorphisms (SNPs) of EGR3 (rs1008949, rs7009708, rs35201266, and rs3750192), SNP rs35201266 in intron 1 of the EGR3 gene showed a significant association with schizophrenia (P?=?0.0008, ?(2)?=?11.156, OR?=?1.493), which withstands multiple testing correction. In addition, the "T-G-C-G" haplotype of EGR3 was under-represented in the patients with schizophrenia (P?=?0.0073, ?(2)?=?7.188, OR?=?0.697). However, an association between the SNPs of EGR2 (rs2295814 and rs2297488) and schizophrenia was not found. These findings are consistent with the previous genetic association of the EGR3 gene in Japanese cohorts, which is the first replication concerning the association of EGR3 with schizophrenia in an independent cohort. Taken together, EGR3 could be suggested as a compelling susceptibility gene in schizophrenia.
SCZ Keywordsschizophrenia, schizophrenic
6Proc. Natl. Acad. Sci. U.S.A. 2012 Jun 109: 9617-22
PMID22645329
TitleErythropoietin-induced changes in brain gene expression reveal induction of synaptic plasticity genes in experimental stroke.
AbstractErythropoietin (EPO) is a neuroprotective cytokine in models of ischemic and nervous system injury, where it reduces neuronal apoptosis and inflammatory cytokines and increases neurogenesis and angiogenesis. EPO also improves cognition in healthy volunteers and schizophrenic patients. We studied the effect of EPO administration on the gene-expression profile in the ischemic cortex of rats after cerebral ischemia at early time points (2 and 6 h). EPO treatment up-regulated genes already increased by ischemia. Hierarchical clustering and analysis of overrepresented functional categories identified genes implicated in synaptic plasticity-Arc, BDNF, Egr1, and EGR2, of which EGR2 was the most significantly regulated. Up-regulation of Arc, BDNF, Dusp5, Egr1, EGR2, Egr4, and Nr4a3 was confirmed by quantitative PCR. We investigated the up-regulation of EGR2/Krox20 further because of its role in neuronal plasticity. Its elevation by EPO was confirmed in an independent in vivo experiment of cerebral ischemia in rats. Using the rat neuroblastoma B104, we found that wild-type cells that do not express EPO receptor (EPOR) do not respond to EPO by inducing EGR2. However, EPOR-expressing B104 cells induce EGR2 early upon incubation with EPO, indicating that EGR2 induction is a direct effect of EPO and that EPOR mediates this effect. Because these changes occur in vivo before decreased inflammatory cytokines or neuronal apoptosis is evident, these findings provide a molecular mechanism for the neuroreparative effects of cytokines and suggest a mechanism of neuroprotection by which promotion of a plastic phenotype results in decreased inflammation and neuronal death.
SCZ Keywordsschizophrenia, schizophrenic
7Prog. Neuropsychopharmacol. Biol. Psychiatry 2012 Oct 39: 149-55
PMID22691714
TitleGenetic and functional analyses of early growth response (EGR) family genes in schizophrenia.
AbstractEarly growth response genes (EGR1, 2, 3, and 4) encode a family of nuclear proteins that function as transcriptional regulators. They are involved in the regulation of synaptic plasticity, learning, and memory, and are implicated in the pathogenesis of schizophrenia.
We conducted a genetic association analysis of 14 SNPs selected from the EGR1, 2, 3, and 4 genes of 564 patients with schizophrenia and 564 control subjects. We also conducted Western blot analysis and promoter activity assay to characterize the EGR genes associated with schizophrenia
We did not detect a true genetic association of these 14 SNPs with schizophrenia in this sample. However, we observed a nominal over-representation of C/C genotype of rs9990 of EGR2 in female schizophrenia as compared to female control subjects (p=0.012, uncorrected for multiple testing). Further study showed that the average mRNA level of the EGR2 gene in the lymphoblastoid cell lines of female schizophrenia patients was significantly higher than that in female control subjects (p=0.002). We also detected a nominal association of 4 SNPs (rs6747506, rs6718289, rs2229294, and rs3813226) of the EGR4 gene that form strong linkage disequilibrium with schizophrenia in males. Reporter gene assay showed that the haplotype T-A derived from rs6747506 and rs6718289 at the promoter region had significantly reduced promoter activity compared with the haplotype A-G.
Our data suggest a tendency of gender-specific association of EGR2 and EGR4 in schizophrenia, with an elevated expression of EGR2 in lympoblastoid cell lines of female schizophrenia patients and a reduced EGR4 gene expression in male schizophrenia patients.
SCZ Keywordsschizophrenia, schizophrenic
8Exp. Mol. Med. 2012 Feb 44: 121-9
PMID22089088
TitleGenetic association of the EGR2 gene with bipolar disorder in Korea.
AbstractThe early growth response gene 2 (EGR2) is located at chromosome 10q21, one of the susceptibility loci in bipolar disorder (BD). EGR2 is involved in cognitive function, myelination, and signal transduction related to neuregulin-ErbB receptor, Bcl-2 family proteins, and brain-derived neurotrophic factor. This study investigated the genetic association of the EGR2 gene with BD and schizophrenia (SPR) in Korea. In 946 subjects (350 healthy controls, 352 patients with BD, and 244 with SPR), nine single nucleotide polymorphisms (SNPs) in the EGR2 gene region were genotyped. Five SNPs showed nominally significant allelic associations with BD (rs2295814, rs61865882, rs10995315, rs2297488, and rs2297489), and the positive associations of all except rs2297488 remained significant after multiple testing correction. Linkage disequilibrium structure analysis revealed two haplotype blocks. Among the common identified haplotypes (frequency > 5%), 'T-G-A-C-T (block 1)' and 'A-A-G-C (block 2)' haplotypes were over-represented, while 'C-G-G-T-T (block 1)' haplotype was under-represented in BD. In contrast, no significant associations were found with SPR. Although an extended analysis with a larger sample size or independent replication is required, these findings suggest a genetic association of EGR2 with BD. Combined with a plausible biological function of EGR2, the EGR2 gene is a possible susceptibility gene in BD.
SCZ Keywordsschizophrenia, schizophrenic
9Mol Brain 2014 -1 7: 74
PMID25298178
TitleBehavioral characterization of mice overexpressing human dysbindin-1.
AbstractThe dysbindin-1 gene (DTNBP1: dystrobrevin binding protein 1) is a promising schizophrenia susceptibility gene, known to localize almost exclusively to neurons in the brain, and participates in the regulation of neurotransmitter release, membrane-surface receptor expression, and synaptic plasticity. Sandy mice, with spontaneous Dtnbp1 deletion, display behavioral abnormalities relevant to symptoms of schizophrenia. However, it remains unknown if dysbindin-1 gain-of-function is beneficial or detrimental.
To answer this question and gain further insight into the pathophysiology and therapeutic potential of dysbindin-1, we developed transgenic mice expressing human DTNBP1 (Dys1A-Tg) and analyzed their behavioral phenotypes. Dys1A-Tg mice were born viable in the expected Mendelian ratios, apparently normal and fertile. Primary screening of behavior and function showed a marginal change in limb grasping in Dys1A-Tg mice. In addition, Dys1A-Tg mice exhibited increased hyperlocomotion after methamphetamine injection. Transcriptomic analysis identified several up- and down-regulated genes, including the immediate-early genes Arc and EGR2, in the prefrontal cortex of Dys1A-Tg mice.
The present findings in Dys1A-Tg mice support the role of dysbindin-1 in psychiatric disorders. The fact that either overexpression (Dys1A-Tg) or underexpression (Sandy) of dysbindin-1 leads to behavioral alterations in mice highlights the functional importance of dysbindin-1 in vivo.
SCZ Keywordsschizophrenia, schizophrenic
10Psychiatry Res 2015 Aug 228: 958-60
PMID26119399
TitleResequencing of early growth response 2 (EGR2) gene revealed a recurrent patient-specific mutation in schizophrenia.
AbstractAbnormal myelination is considered as part of the pathophysiology of schizophrenia. We resequenced the genomic DNA of the EGR2, which has a specific function in the myelination of peripheral nervous system, in 543 schizophrenic patients and 554 non-psychotic controls. We identified six known SNPs, which were not associated with schizophrenia. Nevertheless, we discovered 24 rare mutations, some of them were patient-specific, including a recurrent mutation (p.P173_Y174insP), which might be associated with the pathogenesis of schizophrenia.
SCZ Keywordsschizophrenia, schizophrenic
11Psychiatry Res 2015 Aug 228: 958-60
PMID26119399
TitleResequencing of early growth response 2 (EGR2) gene revealed a recurrent patient-specific mutation in schizophrenia.
AbstractAbnormal myelination is considered as part of the pathophysiology of schizophrenia. We resequenced the genomic DNA of the EGR2, which has a specific function in the myelination of peripheral nervous system, in 543 schizophrenic patients and 554 non-psychotic controls. We identified six known SNPs, which were not associated with schizophrenia. Nevertheless, we discovered 24 rare mutations, some of them were patient-specific, including a recurrent mutation (p.P173_Y174insP), which might be associated with the pathogenesis of schizophrenia.
SCZ Keywordsschizophrenia, schizophrenic