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Shao Y, Sztainberg Y, Wang Q, Bajikar SS, Trostle AJ, Wan YW, Jafar-Nejad P, Rigo F, Liu Z, Tang J, Zoghbi HY. Antisense oligonucleotide therapy in a humanized mouse model of MECP2 duplication syndrome. Sci Transl Med 2021; 13:eaaz7785. [PMID: 33658357 PMCID: PMC8976688 DOI: 10.1126/scitranslmed.aaz7785] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 05/26/2020] [Accepted: 10/01/2020] [Indexed: 12/14/2022]
Abstract
Many intellectual disability disorders are due to copy number variations, and, to date, there have been no treatment options tested for this class of diseases. MECP2 duplication syndrome (MDS) is one of the most common genomic rearrangements in males and results from duplications spanning the methyl-CpG binding protein 2 (MECP2) gene locus. We previously showed that antisense oligonucleotide (ASO) therapy can reduce MeCP2 protein amount in an MDS mouse model and reverse its disease features. This MDS mouse model, however, carried one transgenic human allele and one mouse allele, with the latter being protected from human-specific MECP2-ASO targeting. Because MeCP2 is a dosage-sensitive protein, the ASO must be titrated such that the amount of MeCP2 is not reduced too far, which would cause Rett syndrome. Therefore, we generated an "MECP2 humanized" MDS model that carries two human MECP2 alleles and no mouse endogenous allele. Intracerebroventricular injection of the MECP2-ASO efficiently down-regulated MeCP2 expression throughout the brain in these mice. Moreover, MECP2-ASO mitigated several behavioral deficits and restored expression of selected MeCP2-regulated genes in a dose-dependent manner without any toxicity. Central nervous system administration of MECP2-ASO is therefore well tolerated and beneficial in this mouse model and provides a translatable approach that could be feasible for treating MDS.
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Affiliation(s)
- Yingyao Shao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Qi Wang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sameer S Bajikar
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Alexander J Trostle
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ying-Wooi Wan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | | | - Frank Rigo
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jianrong Tang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
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2
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Olson CO, Pejhan S, Kroft D, Sheikholeslami K, Fuss D, Buist M, Ali Sher A, Del Bigio MR, Sztainberg Y, Siu VM, Ang LC, Sabourin-Felix M, Moss T, Rastegar M. MECP2 Mutation Interrupts Nucleolin-mTOR-P70S6K Signaling in Rett Syndrome Patients. Front Genet 2018; 9:635. [PMID: 30619462 PMCID: PMC6305968 DOI: 10.3389/fgene.2018.00635] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 11/27/2018] [Indexed: 01/26/2023] Open
Abstract
Rett syndrome (RTT) is a severe and rare neurological disorder that is caused by mutations in the X-linked MECP2 (methyl CpG-binding protein 2) gene. MeCP2 protein is an important epigenetic factor in the brain and in neurons. In Mecp2-deficient neurons, nucleoli structures are compromised. Nucleoli are sites of active ribosomal RNA (rRNA) transcription and maturation, a process mainly controlled by nucleolin and mechanistic target of rapamycin (mTOR)-P70S6K signaling. Currently, it is unclear how nucleolin-rRNA-mTOR-P70S6K signaling from RTT cellular model systems translates into human RTT brain. Here, we studied the components of nucleolin-rRNA-mTOR-P70S6K signaling in the brain of RTT patients with common T158M and R255X mutations. Immunohistochemical examination of T158M brain showed disturbed nucleolin subcellular localization, which was absent in Mecp2-deficient homozygous male or heterozygote female mice, compared to wild type (WT). We confirmed by Western blot analysis that nucleolin protein levels are altered in RTT brain, but not in Mecp2-deficient mice. Further, we studied the expression of rRNA transcripts in Mecp2-deficient mice and RTT patients, as downstream molecules that are controlled by nucleolin. By data mining of published ChIP-seq studies, we showed MeCP2-binding at the multi-copy rRNA genes in the mouse brain, suggesting that rRNA might be a direct MeCP2 target gene. Additionally, we observed compromised mTOR-P70S6K signaling in the human RTT brain, a molecular pathway that is upstream of rRNA-nucleolin molecular conduits. RTT patients showed significantly higher phosphorylation of active mTORC1 or mTORC2 complexes compared to age- and sex-matched controls. Correlational analysis of mTORC1/2-P70S6K signaling pathway identified multiple points of deviation from the control tissues that may result in abnormal ribosome biogenesis in RTT brain. To our knowledge, this is the first report of deregulated nucleolin-rRNA-mTOR-P70S6K signaling in the human RTT brain. Our results provide important insight toward understanding the molecular properties of human RTT brain.
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Affiliation(s)
- Carl O Olson
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Shervin Pejhan
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Daniel Kroft
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Kimia Sheikholeslami
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - David Fuss
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Marjorie Buist
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Annan Ali Sher
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Marc R Del Bigio
- Department of Pathology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Victoria Mok Siu
- Division of Medical Genetics, Department of Paediatrics, Schulich School of Medicine, Western University, London, ON, Canada
| | - Lee Cyn Ang
- Department of Pathology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Marianne Sabourin-Felix
- Cancer Division of the Quebec University Hospital Research Centre, Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Tom Moss
- Cancer Division of the Quebec University Hospital Research Centre, Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Mojgan Rastegar
- Regenerative Medicine Program, and Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
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Lombardi LM, Zaghlula M, Sztainberg Y, Baker SA, Klisch TJ, Tang AA, Huang EJ, Zoghbi HY. An RNA interference screen identifies druggable regulators of MeCP2 stability. Sci Transl Med 2018; 9:9/404/eaaf7588. [PMID: 28835516 DOI: 10.1126/scitranslmed.aaf7588] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 04/14/2016] [Accepted: 06/13/2017] [Indexed: 12/14/2022]
Abstract
Alterations in gene dosage due to copy number variation are associated with autism spectrum disorder, intellectual disability (ID), and other psychiatric disorders. The nervous system is so acutely sensitive to the dose of methyl-CpG-binding protein 2 (MeCP2) that even a twofold change in MeCP2 protein-either increased or decreased-results in distinct disorders with overlapping features including ID, autistic behavior, and severe motor dysfunction. Rett syndrome is caused by loss-of-function mutations in MECP2, whereas duplications spanning the MECP2 locus result in MECP2 duplication syndrome (MDS), which accounts for ~1% of X-linked ID. Despite evidence from mouse models that restoring MeCP2 can reverse the course of disease, there are currently no U.S. Food and Drug Administration-approved therapies available to clinically modulate MeCP2 abundance. We used a forward genetic screen against all known human kinases and phosphatases to identify druggable regulators of MeCP2 stability. Two putative modulators of MeCP2, HIPK2 (homeodomain-interacting protein kinase 2) and PP2A (protein phosphatase 2A), were validated as stabilizers of MeCP2 in vivo. Further, pharmacological inhibition of PP2A in vivo reduced MeCP2 in the nervous system and rescued both overexpression and motor abnormalities in a mouse model of MDS. Our findings reveal potential therapeutic targets for treating disorders of altered MECP2 dosage.
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Affiliation(s)
- Laura M Lombardi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Manar Zaghlula
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Steven A Baker
- Department of Pathology, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Tiemo J Klisch
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Amy A Tang
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Eric J Huang
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA. .,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.,Graduate Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
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Abstract
Syndromic autism spectrum disorders represent a group of childhood neurological conditions, typically associated with chromosomal abnormalities or mutations in a single gene. The discovery of their genetic causes has increased our understanding of the molecular pathways critical for normal cognitive and social development. Human studies have revealed that the brain is particularly sensitive to changes in dosage of various proteins from transcriptional and translational regulators to synaptic proteins. Investigations of these disorders in animals have shed light on previously unknown pathogenic mechanisms leading to the identification of potential targets for therapeutic intervention. The demonstration of reversibility of several phenotypes in adult mice is encouraging, and brings hope that with novel therapies, skills and functionality might improve in affected children and young adults. As new research reveals points of convergence between syndromic and nonsyndromic autism spectrum disorders, we believe there will be opportunities for shared therapeutics for this class of conditions.
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Affiliation(s)
- Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas, USA
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5
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Shemesh Y, Forkosh O, Mahn M, Anpilov S, Sztainberg Y, Manashirov S, Shlapobersky T, Elliott E, Tabouy L, Ezra G, Adler ES, Ben-Efraim YJ, Gil S, Kuperman Y, Haramati S, Dine J, Eder M, Deussing JM, Schneidman E, Yizhar O, Chen A. Ucn3 and CRF-R2 in the medial amygdala regulate complex social dynamics. Nat Neurosci 2016; 19:1489-1496. [DOI: 10.1038/nn.4346] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/22/2016] [Indexed: 12/14/2022]
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6
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Ure K, Lu H, Wang W, Ito-Ishida A, Wu Z, He LJ, Sztainberg Y, Chen W, Tang J, Zoghbi HY. Restoration of Mecp2 expression in GABAergic neurons is sufficient to rescue multiple disease features in a mouse model of Rett syndrome. eLife 2016; 5. [PMID: 27328321 PMCID: PMC4946897 DOI: 10.7554/elife.14198] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/09/2016] [Indexed: 12/15/2022] Open
Abstract
The postnatal neurodevelopmental disorder Rett syndrome, caused by mutations in MECP2, produces a diverse array of symptoms, including loss of language, motor, and social skills and the development of hand stereotypies, anxiety, tremor, ataxia, respiratory dysrhythmias, and seizures. Surprisingly, despite the diversity of these features, we have found that deleting Mecp2 only from GABAergic inhibitory neurons in mice replicates most of this phenotype. Here we show that genetically restoring Mecp2 expression only in GABAergic neurons of male Mecp2 null mice enhanced inhibitory signaling, extended lifespan, and rescued ataxia, apraxia, and social abnormalities but did not rescue tremor or anxiety. Female Mecp2+/- mice showed a less dramatic but still substantial rescue. These findings highlight the critical regulatory role of GABAergic neurons in certain behaviors and suggest that modulating the excitatory/inhibitory balance through GABAergic neurons could prove a viable therapeutic option in Rett syndrome. DOI:http://dx.doi.org/10.7554/eLife.14198.001 Rett syndrome is a childhood brain disorder that mainly affects girls and causes symptoms including anxiety, tremors, uncoordinated movements and breathing difficulties. Rett syndrome is caused by mutations in a gene called MECP2, which is found on the X chromosome. Males with MECP2 mutations are rare but have more severe symptoms and die young. Many researchers who study Rett syndrome use mice as a model of the disorder. In particular, male mice with the mouse equivalent of the human MECP2 gene switched off in every cell in the body (also known as Mecp2-null mice) show many of the features of Rett syndrome and die at a young age. The MECP2 gene is important for healthy brain activity. The brain contains two major types of neurons: excitatory neurons, which encourage other neurons to be active; and inhibitory neurons, which stop or dampen the activity of other neurons. In 2010, researchers reported that mice lacking Mecp2 in only their inhibitory neurons develop most of the same problems as those mice with no Mecp2 at all. This discovery led Ure et al. – including a researcher involved in the 2010 study – to ask if activating Mecp2 in the same neurons in otherwise Mecp2-null mice was enough to prevent some of their Rett syndrome-like symptoms. The experiments showed that male mice that only have Mecp2 activated in their inhibitory neurons lived several months longer than male Mecp2-null mice. These male “rescue mice” also moved normally and had a normal body weight, though they still experienced anxiety, tremors and breathing difficulties. Female mice represent a better model of human Rett syndrome patients, and Ure et al. found that female rescue mice showed smaller improvements than the males. These data suggest that when a brain is missing Mecp2 everywhere, as in male Mecp2-null mice, turning on Mecp2 in inhibitory neurons can make the brain network nearly normal and prevent most Rett-syndrome-like symptoms. However, the brains of female rescue mice contain both normal cells and cells with mutated Mecp2. This mixture of normal and abnormal cells appears to cause abnormalities that cannot be overcome by rescuing just the activity of the inhibitory neurons. These findings also highlight the importance of doing future studies in female mice to better understand the development of Rett syndrome. The next challenge is to test different ways of activating the inhibitory neurons in the female mouse brain, for example by using drugs that target these neurons. It is hoped these methods will help researchers to refine a path toward potential new treatments for Rett syndrome patients. Finally, in a related study, Meng et al. asked how deleting or activating Mecp2 only in the excitatory neurons of mice affected Rett-syndrome-like symptoms. DOI:http://dx.doi.org/10.7554/eLife.14198.002
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Affiliation(s)
- Kerstin Ure
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States
| | - Hui Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, United States
| | - Wei Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States
| | - Aya Ito-Ishida
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States
| | - Zhenyu Wu
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Department of Pediatrics, Baylor College of Medicine, Houston, United States
| | - Ling-Jie He
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, United States
| | - Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States
| | - Wu Chen
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Cain Foundation Laboratories, Baylor College of Medicine, Houston, United States
| | - Jianrong Tang
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Department of Pediatrics, Baylor College of Medicine, Houston, United States
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, United States.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States
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Sztainberg Y, Chen HM, Swann JW, Hao S, Tang B, Wu Z, Tang J, Wan YW, Liu Z, Rigo F, Zoghbi HY. Reversal of phenotypes in MECP2 duplication mice using genetic rescue or antisense oligonucleotides. Nature 2015; 528:123-6. [PMID: 26605526 PMCID: PMC4839300 DOI: 10.1038/nature16159] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 10/19/2015] [Indexed: 02/07/2023]
Abstract
Copy number variations have been frequently associated with developmental delay, intellectual disability and autism spectrum disorders. MECP2 duplication syndrome is one of the most common genomic rearrangements in males and is characterized by autism, intellectual disability, motor dysfunction, anxiety, epilepsy, recurrent respiratory tract infections and early death. The broad range of deficits caused by methyl-CpG-binding protein 2 (MeCP2) overexpression poses a daunting challenge to traditional biochemical-pathway-based therapeutic approaches. Accordingly, we sought strategies that directly target MeCP2 and are amenable to translation into clinical therapy. The first question that we addressed was whether the neurological dysfunction is reversible after symptoms set in. Reversal of phenotypes in adult symptomatic mice has been demonstrated in some models of monogenic loss-of-function neurological disorders, including loss of MeCP2 in Rett syndrome, indicating that, at least in some cases, the neuroanatomy may remain sufficiently intact so that correction of the molecular dysfunction underlying these disorders can restore healthy physiology. Given the absence of neurodegeneration in MECP2 duplication syndrome, we propose that restoration of normal MeCP2 levels in MECP2 duplication adult mice would rescue their phenotype. By generating and characterizing a conditional Mecp2-overexpressing mouse model, here we show that correction of MeCP2 levels largely reverses the behavioural, molecular and electrophysiological deficits. We also reduced MeCP2 using an antisense oligonucleotide strategy, which has greater translational potential. Antisense oligonucleotides are small, modified nucleic acids that can selectively hybridize with messenger RNA transcribed from a target gene and silence it, and have been successfully used to correct deficits in different mouse models. We find that antisense oligonucleotide treatment induces a broad phenotypic rescue in adult symptomatic transgenic MECP2 duplication mice (MECP2-TG), and corrected MECP2 levels in lymphoblastoid cells from MECP2 duplication patients in a dose-dependent manner.
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Affiliation(s)
- Yehezkel Sztainberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Hong-mei Chen
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - John W Swann
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Shuang Hao
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Bin Tang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Zhenyu Wu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Jianrong Tang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Ying-Wooi Wan
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Frank Rigo
- Isis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, California 92010, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030, USA
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Shemesh Y, Sztainberg Y, Forkosh O, Shlapobersky T, Chen A, Schneidman E. Correction: High-order social interactions in groups of mice. eLife 2014; 3:e03602. [PMID: 24920500 PMCID: PMC4052486 DOI: 10.7554/elife.03602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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9
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Elharrar E, Warhaftig G, Issler O, Sztainberg Y, Dikshtein Y, Zahut R, Redlus L, Chen A, Yadid G. Overexpression of corticotropin-releasing factor receptor type 2 in the bed nucleus of stria terminalis improves posttraumatic stress disorder-like symptoms in a model of incubation of fear. Biol Psychiatry 2013; 74:827-36. [PMID: 23871471 DOI: 10.1016/j.biopsych.2013.05.039] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 05/21/2013] [Accepted: 05/24/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND Posttraumatic stress disorder (PTSD) is a severe, persistent psychiatric disorder in response to a traumatic event, causing intense anxiety and fear. These responses may increase over time upon conditioning with fear-associated cues, a phenomenon termed fear incubation. Corticotropin-releasing factor receptor type 1 (CRFR1) is involved in activation of the central stress response, while corticotropin-releasing factor receptor type 2 (CRFR2) has been suggested to mediate termination of this response. Corticotropin-releasing factor (CRF) receptors are found in stress-related regions, including the bed nucleus of stria terminalis (BNST), which is implicated in sustained fear. METHODS Fear-related behaviors were analyzed in rats exposed to predator-associated cues, a model of psychological trauma, over 10 weeks. Rats were classified as susceptible (PTSD-like) or resilient. Expression levels of CRF receptors were measured in the amygdala nuclei and BNST of the two groups. In addition, lentiviruses overexpressing CRFR2 were injected into the medial division, posterointermediate part of the BNST (BSTMPI) of susceptible and resilient rats and response to stress cues was measured. RESULTS We found that exposure to stress and stress-associated cues induced a progressive increase in fear response of susceptible rats. The behavioral manifestations of these rats were correlated both with sustained elevation in CRFR1 expression and long-term downregulation in CRFR2 expression in the BSTMPI. Intra-BSTMPI injection of CRFR2 overexpressing lentiviruses attenuated behavioral impairments of susceptible rats. CONCLUSIONS These results implicate the BNST CRF receptors in the mechanism of coping with stress. Our findings suggest increase of CRFR2 levels as a new approach for understanding stress-related atypical psychiatric syndromes such as PTSD.
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Affiliation(s)
- Einat Elharrar
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan; The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan
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Shemesh Y, Sztainberg Y, Forkosh O, Shlapobersky T, Chen A, Schneidman E. High-order social interactions in groups of mice. eLife 2013; 2:e00759. [PMID: 24015357 PMCID: PMC3762363 DOI: 10.7554/elife.00759] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 07/15/2013] [Indexed: 11/25/2022] Open
Abstract
Social behavior in mammals is often studied in pairs under artificial conditions, yet groups may rely on more complicated social structures. Here, we use a novel system for tracking multiple animals in a rich environment to characterize the nature of group behavior and interactions, and show strongly correlated group behavior in mice. We have found that the minimal models that rely only on individual traits and pairwise correlations between animals are not enough to capture group behavior, but that models that include third-order interactions give a very accurate description of the group. These models allow us to infer social interaction maps for individual groups. Using this approach, we show that environmental complexity during adolescence affects the collective group behavior of adult mice, in particular altering the role of high-order structure. Our results provide new experimental and mathematical frameworks for studying group behavior and social interactions. DOI:http://dx.doi.org/10.7554/eLife.00759.001 All animals need to interact with others of the same species, even if it is only to mate. To date, social behavior has been studied mainly at two extremes: detailed observation of pairs; and studies of the collective behavior of large groups, such as flocks of birds. However, to gain an understanding of social behavior in mammals will require an approach that falls between these two extremes. It will be necessary to study animals in larger groups, rather than in pairs, but also to track individuals rather than looking at the activity of the group as a whole. Now, Shemesh et al. have developed a system that can track the behavior of each of four mice with high spatial and temporal resolution as they move around freely in an arena containing ramps, nest boxes, and barriers. Because mice are largely nocturnal, Shemesh et al. dyed the animals’ fur with compounds that produced different coloured fluorescence under ultraviolet light, and then employed an automated system to accurately track each mouse during 12 hr of darkness, over a number of days. Using these data it was possible to estimate the extent to which the behavior of the group is determined by the characteristics of individual mice and how much is determined by interactions between animals. Models based solely on the behavior of individuals could not accurately describe the behavior of the group. Surprisingly, neither could models that focused on interactions between pairs of mice. Only models that included interactions between three mice gave a good approximation of the observed behavior. This shows that, even in a small group, social behavior is determined by relatively complex interactions. Shemesh et al. also found that the behavior of the mice depended on the environment in which they had been raised. Animals that had lived in larger groups and in more interesting enclosures were influenced more by pairwise interactions, and less by three-way interactions, than mice that had been raised in a standard laboratory environment. This suggests that being raised in a complex environment strengthens mouse ‘individuality’. The approach developed by Shemesh et al. could be extended to study larger groups of animals and could also be used to examine the interplay between genes, environment and other factors in shaping social interactions. DOI:http://dx.doi.org/10.7554/eLife.00759.002
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Affiliation(s)
- Yair Shemesh
- Department of Neurobiology , Weizmann Institute of Science , Rehovot , Israel
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Amir-Zilberstein L, Blechman J, Sztainberg Y, Norton WHJ, Reuveny A, Borodovsky N, Tahor M, Bonkowsky JL, Bally-Cuif L, Chen A, Levkowitz G. Homeodomain protein otp and activity-dependent splicing modulate neuronal adaptation to stress. Neuron 2012; 73:279-91. [PMID: 22284183 DOI: 10.1016/j.neuron.2011.11.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2011] [Indexed: 11/19/2022]
Abstract
Regulation of corticotropin-releasing hormone (CRH) activity is critical for the animal's adaptation to stressful challenges, and its dysregulation is associated with psychiatric disorders in humans. However, the molecular mechanism underlying this transcriptional response to stress is not well understood. Using various stress paradigms in mouse and zebrafish, we show that the hypothalamic transcription factor Orthopedia modulates the expression of CRH as well as the splicing factor Ataxin 2-Binding Protein-1 (A2BP1/Rbfox-1). We further show that the G protein coupled receptor PAC1, which is a known A2BP1/Rbfox-1 splicing target and an important mediator of CRH activity, is alternatively spliced in response to a stressful challenge. The generation of PAC1-hop messenger RNA isoform by alternative splicing is required for termination of CRH transcription, normal activation of the hypothalamic-pituitary-adrenal axis and adaptive anxiety-like behavior. Our study identifies an evolutionarily conserved biochemical pathway that modulates the neuronal adaptation to stress through transcriptional activation and alternative splicing.
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Affiliation(s)
- Liat Amir-Zilberstein
- Department of Molecular Cell Biology, Weizmann Institute of Science, P.O. Box 26, Rehovot 76100, Israel
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Sztainberg Y, Kuperman Y, Tsoory M, Lebow M, Chen A. The anxiolytic effect of environmental enrichment is mediated via amygdalar CRF receptor type 1. Mol Psychiatry 2010; 15:905-17. [PMID: 20084060 DOI: 10.1038/mp.2009.151] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Environmental enrichment (EE) is known to have an anxiolytic effect in several animal models; however, the molecular mechanisms underlying these behavioral changes are not understood. In this study, we have shown that the anxiolytic effect of EE is associated with alterations in the corticotropin-releasing factor receptor type 1 (CRFR1) expression levels in the limbic system. We found that the decrease in anxiety-like behavior after housing in enriched conditions was associated with very low levels of CRFR1 mRNA expression in the basolateral amygdala of C57BL/6 mice. We further showed using a lentiviral-based system of RNA interference, that knockdown of CRFR1 mRNA expression in the basolateral amygdala induces a significant decrease in anxiety levels, similar to those achieved by EE nurture. Our data strongly suggest that reduced expression of CRFR1 mRNA levels in the basolateral amygdala mediates the effect of EE on anxiety-like behavior.
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Affiliation(s)
- Y Sztainberg
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
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Abstract
Environmental enrichment for animals is a combination of complex inanimate and social stimulation and generally consists of housing conditions that facilitate enhanced sensory, cognitive, motor and social stimulation relative to standard housing conditions. One of the most robust effects of environmental enrichment is the reduction of anxiety levels. However, the extreme variability in enrichment protocols may account for some of the inconsistencies in its effects and the variance among results reported by different laboratories. In this protocol, we describe a simple environmental enrichment strategy for the induction of a robust and replicable anxiolytic-like effect in mice. We provide detailed instructions on how to build an enrichment cage that is specially designed for easy manipulation, cleaning and observation by the experimenter. In addition, we describe the different enrichment items, their order in the cage, the frequency of renewal and their cleaning and sterilization procedures. The total length of the protocol is 6 weeks.
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Sztainberg Y, Kuperman Y, Issler O, Gil S, Vaughan J, Rivier J, Vale W, Chen A. A novel corticotropin-releasing factor receptor splice variant exhibits dominant negative activity: a putative link to stress-induced heart disease. FASEB J 2009; 23:2186-96. [PMID: 19246489 DOI: 10.1096/fj.08-128066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A growing body of experimental and clinical studies supports a strong association between psychological stress and cardiovascular disease. An important endogenous cardioprotective role in heart physiology has been attributed to corticotropin-releasing factor receptor type 2beta (CRFR2beta). Here, we report the isolation of cDNA from mouse (m) heart encoding a novel CRFR2beta splice variant. Translation of this insertion variant (iv)-mCRFR2beta isoform produces a 421-aa protein that includes a unique C-terminal cytoplasmic tail. Our functional analysis and cellular localization studies demonstrated that when coexpressed with wild-type mCRFR2beta, iv-mCRFR2beta significantly inhibited the wild-type mCRFR2beta membrane expression and its functional signaling by ER-Golgi complex retention, suggesting a dose-dependent dominant negative effect. Interestingly, mice exposed to a 4-wk paradigm of chronic variable stress, a model of chronic psychological stress in humans, presented significantly lower levels of mCRFR2beta and higher levels of iv-mCRFR2beta mRNA expression in their hearts, compared to nonstressed control mice. The dominant-negative effect of iv-mCRFR2beta and its up-regulation by psychological stress suggest a new form of regulation of the mCRFR2beta cardioprotective effect and a potential role for this novel isoform in stress-induced heart disease.
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Affiliation(s)
- Yehezkel Sztainberg
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
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