scholarly journals A novelde novoframeshift deletion inEHMT1in a patient with Kleefstra Syndrome results in decreased H3K9 dimethylation

2017 ◽  
Vol 5 (2) ◽  
pp. 141-146 ◽  
Author(s):  
Patrick R. Blackburn ◽  
Monique Williams ◽  
Margot A. Cousin ◽  
Nicole J. Boczek ◽  
Geoffrey J. Beek ◽  
...  
2021 ◽  
Author(s):  
Mouhamed Alsaqati ◽  
Brittany A Davis ◽  
Jamie Wood ◽  
Megan Jones ◽  
Lora Jones ◽  
...  

SummaryGenetic evidence indicates disrupted epigenetic regulation as a major risk factor for psychiatric disorders, but the molecular mechanisms that drive this association are undetermined. EHMT1 is an epigenetic repressor that is causal for Kleefstra Syndrome (KS), a neurodevelopmental disorder (NDD) leading to ID, and is associated with schizophrenia. Here, we show that reduced EHMT1 activity decreases NRSF/REST protein leading to abnormal neuronal gene expression and progression of neurodevelopment in human iPSC. We further show that EHMT1 regulates NRSF/REST indirectly via repression of miRNA leading to aberrant neuronal gene regulation and neurodevelopment timing. Expression of a NRSF/REST mRNA that lacks the miRNA-binding sites restores neuronal gene regulation to EHMT1 deficient cells. Importantly, the EHMT1-regulated miRNA gene set with elevated expression is enriched for NRSF/REST regulators with an association for ID and schizophrenia. This reveals a molecular interaction between H3K9 dimethylation and NSRF/REST contributing to the aetiology of psychiatric disorders.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Monica Frega ◽  
Katrin Linda ◽  
Jason M. Keller ◽  
Güvem Gümüş-Akay ◽  
Britt Mossink ◽  
...  

Abstract Kleefstra syndrome (KS) is a neurodevelopmental disorder caused by mutations in the histone methyltransferase EHMT1. To study the impact of decreased EHMT1 function in human cells, we generated excitatory cortical neurons from induced pluripotent stem (iPS) cells derived from KS patients. Neuronal networks of patient-derived cells exhibit network bursting with a reduced rate, longer duration, and increased temporal irregularity compared to control networks. We show that these changes are mediated by upregulation of NMDA receptor (NMDAR) subunit 1 correlating with reduced deposition of the repressive H3K9me2 mark, the catalytic product of EHMT1, at the GRIN1 promoter. In mice EHMT1 deficiency leads to similar neuronal network impairments with increased NMDAR function. Finally, we rescue the KS patient-derived neuronal network phenotypes by pharmacological inhibition of NMDARs. Summarized, we demonstrate a direct link between EHMT1 deficiency and NMDAR hyperfunction in human neurons, providing a potential basis for more targeted therapeutic approaches for KS.


2019 ◽  
Author(s):  
Evelien H.S. Schut ◽  
Alejandra Alonso ◽  
Steven Smits ◽  
Mehdi Khamassi ◽  
Anumita Samanta ◽  
...  

AbstractKleefstra syndrome is a disorder caused by a mutation in the EHMT1 gene characterized in humans by general developmental delay, mild to severe intellectual disability and autism. Here, we characterized semantic- and episodic-like memory in the Ehmt1+/- mouse model using the Object Space Task. We combined conventional behavioral analysis with automated analysis by deep-learning networks, a session-based computational learning model and a trial-based classifier. Ehmt1+/- mice showed more anxiety-like features and generally explored objects less, but the difference decreased over time. Interestingly, when analyzing memory-specific exploration, Ehmt1+/- show increased expression of semantic-like memory, but a deficit in episodic-like memory. A similar dissociation of semantic and episodic memory performance has been previously reported in humans with autism. Using our automatic classifier to differentiate between genotypes, we found that semantic-like memory features are better suited for classification than general exploration differences. Thus, detailed behavioral classification with the Object Space Task produced a more detailed behavioral phenotype of the Ehmt1+/- mouse model.One Sentence SummaryEhmt1+/- mice show decreased exploration and episodic-like memory but increased semantic-like memory In the Object Space Task. (143 of 150)


2010 ◽  
Vol 52 (4) ◽  
pp. 420-430 ◽  
Author(s):  
Bo Ding ◽  
Yan Zhu ◽  
Zhong-Yuan Bu ◽  
Wen-Hui Shen ◽  
Yu Yu ◽  
...  

2009 ◽  
Vol 21 (1) ◽  
pp. 205
Author(s):  
K. E. Park ◽  
R. Cabot

Methylation of the lysine 9 residue of histone H3 (H3K9) is linked with repression of transcription. Dimethylated H3K9 adopts a strict asymmetrical distribution in murine zygotes, with dimethylated H3K9 detectable only on maternally derived chromatin. In contrast, both male and female pronuclei in porcine zygotes can possess dimethylated H3K9; however, some asymmetry in H3K9 dimethylation exists between individual pronuclei, particularly in polyspermic embryos. The objective of this study was to determine the extent that DNA, mRNA, and protein synthesis serve in maintaining the asymmetrical distribution of dimethylated H3K9 in porcine zygotes. We hypothesized that the distribution of dimethylated H3K9 between individual pronuclei would not depend on alternations in chromatin structure induced by DNA or mRNA synthesis but would be affected by protein synthesis. To test this hypothesis, in vitro-matured porcine oocytes were fertilized in vitro, cultured in porcine zygote medium-3 containing 3 mg mL–1 of BSA, and allocated to 1 of 4 treatment groups: (1) incubation with 25 μg mL–1 of α-amanitin (α-AM), (2) incubation with 3 μg mL–1 of aphidicolin (APH), (3) incubation with 50 μg mL–1 of cycloheximide (CYC), and (4) nontreated controls. Embryos were removed from each treatment group at 10, 15, 20, and 25 h post gamete mixing, fixed, and processed to detect dimethylated H3K9 immunocytochemically. For monospermic embryos in the control group, 24% (7/29), 31% (8/26), 30% (7/24), and 20% (4/20) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For polyspermic embryos in the control group, 82% (32/39), 78% (31/40), 74% (28/38), and 65% (24/37) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For monospermic embryos in the α-AM group, 29% (4/14), 14% (2/14), 8% (1/12), and 11% (1/9) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For polyspermic embryos in the α-AM group, 71% (15/21), 63% (12/19), 55% (10/18), and 47% (8/17) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For monospermic embryos in the APH group, 31% (4/13), 23% (3/13), 23% (3/13), and 18% (2/11) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For polyspermic embryos in the APH group, 75% (15/20), 67% (12/18), 63% (12/19), and 56% (10/18) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For monospermic embryos in the CYC group, 33% (5/15), 25% (4/16), 14% (2/14), and 9% (1/11) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. For polyspermic embryos in the CYC group, 78% (18/23), 67% (16/24), 58% (14/24), and 59% (13/22) showed differential localization between pronuclei at 10, 15, 20, and 25 h, respectively. These results suggest that the distribution of dimethylated H3K9 between pronuclei is not affected by DNA, mRNA, or protein synthesis (P > 0.05), but is affected by the age of the pronuclei (P < 0.05).


2020 ◽  
Vol 4 ◽  
pp. 239821282092864
Author(s):  
Brittany A Davis ◽  
François David ◽  
Ciara O’Regan ◽  
Manal A Adam ◽  
Adrian J Harwood ◽  
...  

Regulators of chromatin dynamics and transcription are increasingly implicated in the aetiology of neurodevelopmental disorders. Haploinsufficiency of EHMT1, encoding a histone methyltransferase, is associated with several neurodevelopmental disorders, including Kleefstra syndrome, developmental delay and autism spectrum disorder. Using a mouse model of Ehmt1 haploinsufficiency ( Ehmt1D6Cre/+), we examined a number of brain and behavioural endophenotypes of relevance to neurodevelopmental disorders. Specifically, we show that Ehmt1D6Cre/+ mice have deficits in information processing, evidenced by abnormal sensory-motor gating, a complete absence of object recognition memory, and a reduced magnitude of auditory evoked potentials in both paired-pulse inhibition and mismatch negativity. The electrophysiological experiments show that differences in magnitude response to auditory stimulus were associated with marked reductions in total and evoked beta- and gamma-band oscillatory activity, as well as significant reductions in phase synchronisation. The pattern of electrophysiological deficits in Ehmt1D6Cre/+ matches those seen in control mice following administration of the selective NMDA-R antagonist, ketamine. This, coupled with reduction of Grin1 mRNA expression in Ehmt1D6Cre/+ hippocampus, suggests that Ehmt1 haploinsufficiency may lead to disruption in NMDA-R. Taken together, these data indicate that reduced Ehmt1 dosage during forebrain development leads to abnormal circuitry formation, which in turn results in profound information processing deficits. Such information processing deficits are likely paramount to our understanding of the cognitive and neurological dysfunctions shared across the neurodevelopmental disorders associated with EHMT1 haploinsufficiency.


2004 ◽  
Vol 24 (12) ◽  
pp. 5475-5484 ◽  
Author(s):  
Claire Rougeulle ◽  
Julie Chaumeil ◽  
Kavitha Sarma ◽  
C. David Allis ◽  
Danny Reinberg ◽  
...  

ABSTRACT Histone H3 tail modifications are among the earliest chromatin changes in the X-chromosome inactivation process. In this study we investigated the relative profiles of two important repressive marks on the X chromosome: methylation of H3 lysine 9 (K9) and 27 (K27). We found that both H3K9 dimethylation and K27 trimethylation characterize the inactive X in somatic cells and that their relative kinetics of enrichment on the X chromosome as it undergoes inactivation are similar. However, dynamic changes of H3K9 and H3K27 methylation on the inactivating X chromosome compared to the rest of the genome are distinct, suggesting that these two modifications play complementary and perhaps nonredundant roles in the establishment and/or maintenance of X inactivation. Furthermore, we show that a hotspot of H3K9 dimethylation 5′ to Xist also displays high levels of H3 tri-meK27. However, analysis of this region in G9a mutant embryonic stem cells shows that these two methyl marks are dependent on different histone methyltransferases.


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