1
|
Wang X, Mei D, Gou L, Zhao S, Gao C, Guo J, Luo S, Guo B, Yang Z, Wang Q, Tan T, Zhang Y. Functional Evaluation of a Novel GRIN2B Missense Variant Associated with Epilepsy and Intellectual Disability. Neuroscience 2023; 526:107-120. [PMID: 37385334 DOI: 10.1016/j.neuroscience.2023.06.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/17/2023] [Accepted: 06/21/2023] [Indexed: 07/01/2023]
Abstract
Epilepsy, a neurological condition, is widely prevalent among individuals with intellectual disability (ID). It is well established that N-methyl-D-aspartate (NMDA) receptors play an important role in both epilepsy and ID. Autosomal dominant mutations in the GRIN2B gene, which encodes the GluN2B subunit of the NMDA receptor, have been reported to be associated with epilepsy and ID. However, the underlying mechanism of this association is not well-understood. In this study, we identified a novel GRIN2B mutation (c.3272A > C, p.K1091T) in a patient with epilepsy and ID. The proband was a one year and ten months old girl. GRIN2B variant was inherited from her mother. We further investigated the functional consequences of this mutation. Our findings revealed that the p.K1091T mutation created a Casein kinase 2 phosphorylation site. Using recombinant NMDA receptors containing the GluN2B-K1091T along with GluN1 in HEK 293T cells, we observed significant defects in its interactions with postsynaptic density 95. It is accompanied by reduced delivery of the receptors to the cell membrane and a decrease in glutamate affinity. Moreover, primary neurons expressing GluN2B-K1091T also exhibited impaired surface expression of NMDA receptors, a reduction in dendritic spine number and excitatory synaptic transmission. In summary, our study reports a novel GRIN2B mutation and provides functional characteristics of this mutation in vitro, thereby contributing to the understanding of GRIN2B variants in epilepsy and ID.
Collapse
Affiliation(s)
- Xiaona Wang
- Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Engineering Research Center of Childhood Neurodevelopment, Zhengzhou 450018, Henan, China.
| | - Daoqi Mei
- Department of Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou 450018, Henan, China
| | - Lingshan Gou
- Center for Genetic Medicine, Xuzhou Maternity and Child Health Care Hospital Affiliated to Xuzhou Medical University, Xuzhou 221000, Jiangsu, China
| | - Shuai Zhao
- Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Engineering Research Center of Childhood Neurodevelopment, Zhengzhou 450018, Henan, China
| | - Chao Gao
- Department of Rehabilitation, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, Henan, China
| | - Jisheng Guo
- School of Basic Medical Sciences, Yantai Campus of Binzhou Medical University, Yantai 264003, Shandong, China
| | - Shuying Luo
- Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Engineering Research Center of Childhood Neurodevelopment, Zhengzhou 450018, Henan, China
| | - Bin Guo
- School of Traditional Chinese Medicine, Ningxia Medical University, Ningxia 750004, China
| | - Zhigang Yang
- Department of Neurology, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Zhengzhou 450018, Henan, China
| | - Qi Wang
- Department of Histology and Embryology, School of Basic Medicine, Guizhou Medical University, Guiyang 550025, Guizhou, China.
| | - Tao Tan
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Key Laboratory of Alzheimer's Disease of Zhejiang Province, Institute of Aging, Wenzhou Medical University, Wenzhou 325000, Zhejiang, China.
| | - Yaodong Zhang
- Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou Children's Hospital, Henan Provincial Key Laboratory of Children's Genetics and Metabolic Diseases, Henan Engineering Research Center of Childhood Neurodevelopment, Zhengzhou 450018, Henan, China.
| |
Collapse
|
2
|
Anne A, Saxena S, Mohan KN. Genome-wide methylation analysis of post-mortem cerebellum samples supports the role of peroxisomes in autism spectrum disorder. Epigenomics 2022; 14:1015-1027. [PMID: 36154275 DOI: 10.2217/epi-2022-0184] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: We tested the hypothesis that a subset of patients with autism spectrum disorder (ASD) contains candidate genes with high DNA methylation differences (effective values) that potentially affect one of the two alleles. Materials & methods: Genome-wide DNA methylation comparisons were made on cerebellum samples from 30 patients and 45 controls. Results: 12 genes with high effective values, including GSDMD, MMACHC, SLC6A5 and NKX6-2, implicated in ASD and other neuropsychiatric disorders were identified. Monoallelic promoter methylation and downregulation were observed for SERHL (serine hydrolase-like) and CAT (catalase) genes associated with peroxisome function. Conclusion: These data are consistent with the hypothesis implicating impaired peroxisome function/biogenesis for ASD. A similar approach holds promise for identifying rare epimutations in ASD and other complex disorders.
Collapse
Affiliation(s)
- Anuhya Anne
- Molecular Biology and Genetics Laboratory, Department of Biological Sciences, Birla Institute of Technology & Science, Pilani - Hyderabad Campus, 500 078, India.,Centre for Human Disease Research, Birla Institute of Technology & Science, Pilani - Hyderabad Campus, 500 078, India
| | - Sonal Saxena
- Molecular Biology and Genetics Laboratory, Department of Biological Sciences, Birla Institute of Technology & Science, Pilani - Hyderabad Campus, 500 078, India
| | - Kommu Naga Mohan
- Molecular Biology and Genetics Laboratory, Department of Biological Sciences, Birla Institute of Technology & Science, Pilani - Hyderabad Campus, 500 078, India.,Centre for Human Disease Research, Birla Institute of Technology & Science, Pilani - Hyderabad Campus, 500 078, India
| |
Collapse
|
3
|
Gaik M, Kojic M, Stegeman MR, Öncü‐Öner T, Kościelniak A, Jones A, Mohamed A, Chau PYS, Sharmin S, Chramiec‐Głąbik A, Indyka P, Rawski M, Biela A, Dobosz D, Millar A, Chau V, Ünalp A, Piper M, Bellingham MC, Eichler EE, Nickerson DA, Güleryüz H, Abbassi NEH, Jazgar K, Davis MJ, Mercimek‐Andrews S, Cingöz S, Wainwright BJ, Glatt S. Functional divergence of the two Elongator subcomplexes during neurodevelopment. EMBO Mol Med 2022; 14:e15608. [PMID: 35698786 PMCID: PMC9260213 DOI: 10.15252/emmm.202115608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 05/20/2022] [Accepted: 05/23/2022] [Indexed: 12/11/2022] Open
Abstract
The highly conserved Elongator complex is a translational regulator that plays a critical role in neurodevelopment, neurological diseases, and brain tumors. Numerous clinically relevant variants have been reported in the catalytic Elp123 subcomplex, while no missense mutations in the accessory subcomplex Elp456 have been described. Here, we identify ELP4 and ELP6 variants in patients with developmental delay, epilepsy, intellectual disability, and motor dysfunction. We determine the structures of human and murine Elp456 subcomplexes and locate the mutated residues. We show that patient-derived mutations in Elp456 affect the tRNA modification activity of Elongator in vitro as well as in human and murine cells. Modeling the pathogenic variants in mice recapitulates the clinical features of the patients and reveals neuropathology that differs from the one caused by previously characterized Elp123 mutations. Our study demonstrates a direct correlation between Elp4 and Elp6 mutations, reduced Elongator activity, and neurological defects. Foremost, our data indicate previously unrecognized differences of the Elp123 and Elp456 subcomplexes for individual tRNA species, in different cell types and in different key steps during the neurodevelopment of higher organisms.
Collapse
|
4
|
Specchio N, Ferretti A. Phenotypic overlap and genetic challenges in neurodevelopmental disorders. Dev Med Child Neurol 2021; 63:1368. [PMID: 34495545 DOI: 10.1111/dmcn.15053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/10/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Alessandro Ferretti
- Rare and Complex Epilepsy Unit, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| |
Collapse
|