1
|
Abstract
Our social environment, from the microscopic to the macro-social, affects us for the entirety of our lives. One integral line of research to examine how interpersonal and societal environments can get "under the skin" is through the lens of epigenetics. Epigenetic mechanisms are adaptations made to our genome in response to our environment which include tags placed on and removed from the DNA itself to how our DNA is packaged, affecting how our genes are read, transcribed, and interact. These tags are affected by social environments and can persist over time; this may aid us in responding to experiences and exposures, both the enriched and the disadvantageous. From memory formation to immune function, the experience-dependent plasticity of epigenetic modifications to micro- and macro-social environments may contribute to the process of learning from comfort, pain, and stress to better survive in whatever circumstances life has in store.
Collapse
Affiliation(s)
- Sarah M Merrill
- Centre for Molecular Medicine and Therapeutics, British Columbia Children's Hospital, Vancouver, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Nicole Gladish
- Centre for Molecular Medicine and Therapeutics, British Columbia Children's Hospital, Vancouver, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Michael S Kobor
- Centre for Molecular Medicine and Therapeutics, British Columbia Children's Hospital, Vancouver, BC, Canada.
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada.
- Human Early Learning Partnership, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
2
|
Affiliation(s)
- Andre Fischer
- Department for Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany.
- Department for Systems Medicine and Brain Diseases, German Center for Neurodegenerative Diseases (DZNE) site Göttingen, Göttingen, Germany.
| |
Collapse
|
3
|
Weaver ICG, Korgan AC, Lee K, Wheeler RV, Hundert AS, Goguen D. Stress and the Emerging Roles of Chromatin Remodeling in Signal Integration and Stable Transmission of Reversible Phenotypes. Front Behav Neurosci 2017; 11:41. [PMID: 28360846 PMCID: PMC5350110 DOI: 10.3389/fnbeh.2017.00041] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 02/24/2017] [Indexed: 01/02/2023] Open
Abstract
The influence of early life experience and degree of parental-infant attachment on emotional development in children and adolescents has been comprehensively studied. Structural and mechanistic insight into the biological foundation and maintenance of mammalian defensive systems (metabolic, immune, nervous and behavioral) is slowly advancing through the emerging field of developmental molecular (epi)genetics. Initial evidence revealed that differential nurture early in life generates stable differences in offspring hypothalamic-pituitary-adrenal (HPA) regulation, in part, through chromatin remodeling and changes in DNA methylation of specific genes expressed in the brain, revealing physical, biochemical and molecular paths for the epidemiological concept of gene-environment interactions. Herein, a primary molecular mechanism underpinning the early developmental programming and lifelong maintenance of defensive (emotional) responses in the offspring is the alteration of chromatin domains of specific genomic regions from a condensed state (heterochromatin) to a transcriptionally accessible state (euchromatin). Conversely, DNA methylation promotes the formation of heterochromatin, which is essential for gene silencing, genomic integrity and chromosome segregation. Therefore, inter-individual differences in chromatin modifications and DNA methylation marks hold great potential for assessing the impact of both early life experience and effectiveness of intervention programs—from guided psychosocial strategies focused on changing behavior to pharmacological treatments that target chromatin remodeling and DNA methylation enzymes to dietary approaches that alter cellular pools of metabolic intermediates and methyl donors to affect nutrient bioavailability and metabolism. In this review article, we discuss the potential molecular mechanism(s) of gene regulation associated with chromatin modeling and programming of endocrine (e.g., HPA and metabolic or cardiovascular) and behavioral (e.g., fearfulness, vigilance) responses to stress, including alterations in DNA methylation and the role of DNA repair machinery. From parental history (e.g., drugs, housing, illness, nutrition, socialization) to maternal-offspring exchanges of nutrition, microbiota, antibodies and stimulation, the nature of nurture provides not only mechanistic insight into how experiences propagate from external to internal variables, but also identifies a composite therapeutic target, chromatin modeling, for gestational/prenatal stress, adolescent anxiety/depression and adult-onset neuropsychiatric disease.
Collapse
Affiliation(s)
- Ian C G Weaver
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| | - Austin C Korgan
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| | - Kristen Lee
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| | - Ryan V Wheeler
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| | - Amos S Hundert
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| | - Donna Goguen
- Department of Psychology and Neuroscience, and Department of Psychiatry, Dalhousie University Halifax, NS, Canada
| |
Collapse
|
4
|
Dissociation of Cross-Sectional Trajectories for Verbal and Visuo-Spatial Working Memory Development in Rubinstein-Taybi Syndrome. J Autism Dev Disord 2017; 46:2064-2071. [PMID: 27011324 PMCID: PMC4860195 DOI: 10.1007/s10803-016-2736-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Working memory (WM) impairments might amplify behavioural difference in genetic syndromes. Murine models of Rubinstein–Taybi syndrome (RTS) evidence memory impairments but there is limited research on memory in RTS. Individuals with RTS and typically developing children completed WM tasks, with participants with RTS completing an IQ assessment and parents/carers completing the Vineland Adaptive Behavior Scales. A cross-sectional trajectory analysis was conducted. There were significant WM span deficits in RTS relative to mental age. Verbal WM span was positively associated with mental age; however, this was not observed for visuo-spatial span. There is a dissociation between WM domains in RTS. Individuals may have difficulties with tasks relying on WM span, above difficulties predicted by overall ability.
Collapse
|
5
|
Abstract
The last decade has been marked by an increased interest in relating epigenetic mechanisms to complex human behaviors, although this interest has not been balanced, accentuating various types of affective and primarily ignoring cognitive functioning. Recent animal model data support the view that epigenetic processes play a role in learning and memory consolidation and help transmit acquired memories even across generations. In this review, we provide an overview of various types of epigenetic mechanisms in the brain (DNA methylation, histone modification, and noncoding RNA action) and discuss their impact proximally on gene transcription, protein synthesis, and synaptic plasticity and distally on learning, memory, and other cognitive functions. Of particular importance are observations that neuronal activation regulates the dynamics of the epigenome's functioning under precise timing, with subsequent alterations in the gene expression profile. In turn, epigenetic regulation impacts neuronal action, closing the circle and substantiating the signaling pathways that underlie, at least partially, learning, memory, and other cognitive processes.
Collapse
|
6
|
Mitrousis N, Tropepe V, Hermanson O. Post-Translational Modifications of Histones in Vertebrate Neurogenesis. Front Neurosci 2015; 9:483. [PMID: 26733796 PMCID: PMC4689847 DOI: 10.3389/fnins.2015.00483] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 12/04/2015] [Indexed: 11/13/2022] Open
Abstract
The process of neurogenesis, through which the entire nervous system of an organism is formed, has attracted immense scientific attention for decades. How can a single neural stem cell give rise to astrocytes, oligodendrocytes, and neurons? Furthermore, how is a neuron led to choose between the hundreds of different neuronal subtypes that the vertebrate CNS contains? Traditionally, niche signals and transcription factors have been on the spotlight. Recent research is increasingly demonstrating that the answer may partially lie in epigenetic regulation of gene expression. In this article, we comprehensively review the role of post-translational histone modifications in neurogenesis in both the embryonic and adult CNS.
Collapse
Affiliation(s)
- Nikolaos Mitrousis
- Institute of Biomaterials and Biomedical Engineering, University of Toronto Toronto, ON, Canada
| | - Vincent Tropepe
- Department of Cell and Systems Biology, Centre for the Analysis of Genome Evolution and Function, University of Toronto Toronto, ON, Canada
| | - Ola Hermanson
- Department of Neuroscience, Karolinska Institutet Stockholm, Sweden
| |
Collapse
|
7
|
Stilling RM, Rönicke R, Benito E, Urbanke H, Capece V, Burkhardt S, Bahari-Javan S, Barth J, Sananbenesi F, Schütz AL, Dyczkowski J, Martinez-Hernandez A, Kerimoglu C, Dent SYR, Bonn S, Reymann KG, Fischer A. K-Lysine acetyltransferase 2a regulates a hippocampal gene expression network linked to memory formation. EMBO J 2014; 33:1912-27. [PMID: 25024434 DOI: 10.15252/embj.201487870] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Neuronal histone acetylation has been linked to memory consolidation, and targeting histone acetylation has emerged as a promising therapeutic strategy for neuropsychiatric diseases. However, the role of histone-modifying enzymes in the adult brain is still far from being understood. Here we use RNA sequencing to screen the levels of all known histone acetyltransferases (HATs) in the hippocampal CA1 region and find that K-acetyltransferase 2a (Kat2a)--a HAT that has not been studied for its role in memory function so far--shows highest expression. Mice that lack Kat2a show impaired hippocampal synaptic plasticity and long-term memory consolidation. We furthermore show that Kat2a regulates a highly interconnected hippocampal gene expression network linked to neuroactive receptor signaling via a mechanism that involves nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). In conclusion, our data establish Kat2a as a novel and essential regulator of hippocampal memory consolidation.
Collapse
Affiliation(s)
- Roman M Stilling
- Department of Psychiatry and Psychotherapy, University Medical Center, Göttingen, Germany
| | - Raik Rönicke
- Research group for Pathophysiology in Dementia, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Eva Benito
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Hendrik Urbanke
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Vincenzo Capece
- Research group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Susanne Burkhardt
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Sanaz Bahari-Javan
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Jonas Barth
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Farahnaz Sananbenesi
- Department of Psychiatry and Psychotherapy, University Medical Center, Göttingen, Germany
| | - Anna L Schütz
- Research group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Jerzy Dyczkowski
- Research group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Ana Martinez-Hernandez
- Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Cemil Kerimoglu
- Department of Psychiatry and Psychotherapy, University Medical Center, Göttingen, Germany
| | - Sharon Y R Dent
- MD Anderson Cancer Center, University of Texas, Smithville, TX, USA
| | - Stefan Bonn
- Research group for Computational Analysis of Biological Networks, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Klaus G Reymann
- Research group for Pathophysiology in Dementia, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Andre Fischer
- Department of Psychiatry and Psychotherapy, University Medical Center, Göttingen, Germany Research group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| |
Collapse
|
8
|
Sheikh BN. Crafting the brain - role of histone acetyltransferases in neural development and disease. Cell Tissue Res 2014; 356:553-73. [PMID: 24788822 DOI: 10.1007/s00441-014-1835-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 01/30/2014] [Indexed: 01/19/2023]
Abstract
The human brain is a highly specialized organ containing nearly 170 billion cells with specific functions. Development of the brain requires adequate proliferation, proper cell migration, differentiation and maturation of progenitors. This is in turn dependent on spatial and temporal coordination of gene transcription, which requires the integration of both cell intrinsic and environmental factors. Histone acetyltransferases (HATs) are one family of proteins that modulate expression levels of genes in a space- and time-dependent manner. HATs and their molecular complexes are able to integrate multiple molecular inputs and mediate transcriptional levels by acetylating histone proteins. In mammals, 19 HATs have been described and are separated into five families (p300/CBP, MYST, GNAT, NCOA and transcription-related HATs). During embryogenesis, individual HATs are expressed or activated at specific times and locations to coordinate proper development. Not surprisingly, mutations in HATs lead to severe developmental abnormalities in the nervous system and increased neurodegeneration. This review focuses on our current understanding of HATs and their biological roles during neural development.
Collapse
Affiliation(s)
- Bilal N Sheikh
- Division of Development and Cancer, The Walter and Eliza Hall Institute of Medical Research, Melbourne, 3052, Victoria, Australia,
| |
Collapse
|
9
|
Abstract
Recent data support the view that epigenetic processes play a role in memory consolidation and help to transmit acquired memories even across generations in a Lamarckian manner. Drugs that target the epigenetic machinery were found to enhance memory function in rodents and ameliorate disease phenotypes in models for brain diseases such as Alzheimer's disease, Chorea Huntington, Depression or Schizophrenia. In this review, I will give an overview on the current knowledge of epigenetic processes in memory function and brain disease with a focus on Morbus Alzheimer as the most common neurodegenerative disease. I will address the question whether an epigenetic therapy could indeed be a suitable therapeutic avenue to treat brain diseases and discuss the necessary steps that should help to take neuroepigenetic research to the next level.
Collapse
Affiliation(s)
- Andre Fischer
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| |
Collapse
|
10
|
Weaver ICG. Integrating early life experience, gene expression, brain development, and emergent phenotypes: unraveling the thread of nature via nurture. ADVANCES IN GENETICS 2014; 86:277-307. [PMID: 25172353 DOI: 10.1016/b978-0-12-800222-3.00011-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adaptation to environmental changes is based on the perpetual generation of new phenotypes. Modern biology has focused on the role of epigenetic mechanisms in facilitating the adaptation of organisms to changing environments through alterations in gene expression. Inherited and/or acquired epigenetic factors are relatively stable and have regulatory roles in numerous genomic activities that translate into phenotypic outcomes. Evidence that dietary and pharmacological interventions have the potential to reverse environment-induced modification of epigenetic states (e.g., early life experience, nutrition, medication, infection) has provided an additional stimulus for understanding the biological basis of individual differences in cognitive abilities and disorders of the brain. It has been suggested that accurate quantification of the relative contribution of heritable genetic and epigenetic variation is essential for understanding phenotypic divergence and adaptation in changing environments, a process requiring stable modulation of gene expression. The main challenge for epigenetics in psychology and psychiatry is to determine how experiences and environmental cues, including the nature of our nurture, influence the expression of neuronal genes to produce long-term individual differences in behavior, cognition, personality, and mental health. To this end, focusing on DNA and histone modifications and their initiators, mediators and readers may provide new inroads for understanding the molecular basis of phenotypic plasticity and disorders of the brain. In this chapter, we review recent discoveries highlighting epigenetic aspects of normal brain development and mental illness, as well as discuss some future directions in the field of behavioral epigenetics.
Collapse
Affiliation(s)
- Ian C G Weaver
- Department of Psychology and Neuroscience, Dalhousie University, Nova Scotia, Canada; Department of Psychiatry, Dalhousie University, Nova Scotia, Canada
| |
Collapse
|
11
|
Bhattacharya A, Klann E. The molecular basis of cognitive deficits in pervasive developmental disorders. Learn Mem 2012; 19:434-43. [PMID: 22904374 DOI: 10.1101/lm.025007.111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Persons with pervasive developmental disorders (PDD) exhibit a range of cognitive deficits that hamper their quality of life, including difficulties involving communication, sociability, and perspective-taking. In recent years, a variety of studies in mice that model genetic syndromes with a high risk of PDD have provided insights into the underlying molecular mechanisms associated with these disorders. What is less appreciated is how the molecular anomalies affect neuronal and circuit function to give rise to the cognitive deficits associated with PDD. In this review, we describe genetic mutations that cause PDD and discuss how they alter fundamental social and cognitive processes. We then describe efforts to correct cognitive impairments associated with these disorders and identify areas of further inquiry in the search for molecular targets for therapeutics for PDD.
Collapse
Affiliation(s)
- Aditi Bhattacharya
- Center for Neural Science, New York University, New York, New York 10003, USA
| | | |
Collapse
|
12
|
Ablation of CBP in forebrain principal neurons causes modest memory and transcriptional defects and a dramatic reduction of histone acetylation but does not affect cell viability. J Neurosci 2011; 31:1652-63. [PMID: 21289174 DOI: 10.1523/jneurosci.4737-10.2011] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Rubinstein-Taybi syndrome (RSTS) is an inheritable disease associated with mutations in the gene encoding the CREB (cAMP response element-binding protein)-binding protein (CBP) and characterized by growth impairment, learning disabilities, and distinctive facial and skeletal features. Studies in mouse models for RSTS first suggested a direct role for CBP and histone acetylation in cognition and memory. Here, we took advantage of the genetic tools for generating mice in which the CBP gene is specifically deleted in postmitotic principal neurons of the forebrain to investigate the consequences of the loss of CBP in the adult brain. In contrast to the conventional CBP knock-out mice, which exhibit very early embryonic lethality, postnatal forebrain-restricted CBP mutants were viable and displayed no overt abnormalities. We identified the dimer of histones H2A and H2B as the preferred substrate of the histone acetyltransferase domain of CBP. Surprisingly, the loss of CBP and subsequent histone hypoacetylation had a very modest impact in the expression of a number of immediate early genes and did not affect neuronal viability. In addition, the behavioral characterization of these mice dissociated embryonic and postnatal deficits caused by impaired CBP function, narrowed down the anatomical substrate of specific behavioral defects, and confirmed the special sensitivity of object recognition memory to CBP deficiency. Overall, our study provides novel insights into RSTS etiology and clarifies some of the standing questions concerning the role of CBP and histone acetylation in activity-driven gene expression, memory formation, and neurodegeneration.
Collapse
|
13
|
Wang J, Weaver ICG, Gauthier-Fisher A, Wang H, He L, Yeomans J, Wondisford F, Kaplan DR, Miller FD. CBP histone acetyltransferase activity regulates embryonic neural differentiation in the normal and Rubinstein-Taybi syndrome brain. Dev Cell 2010; 18:114-25. [PMID: 20152182 DOI: 10.1016/j.devcel.2009.10.023] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 08/10/2009] [Accepted: 10/27/2009] [Indexed: 01/04/2023]
Abstract
Increasing evidence indicates that epigenetic changes regulate cell genesis. Here, we ask about neural precursors, focusing on CREB binding protein (CBP), a histone acetyltransferase that, when haploinsufficient, causes Rubinstein-Taybi syndrome (RTS), a genetic disorder with cognitive dysfunction. We show that neonatal cbp(+/-) mice are behaviorally impaired, displaying perturbed vocalization behavior. cbp haploinsufficiency or genetic knockdown with siRNAs inhibited differentiation of embryonic cortical precursors into all three neural lineages, coincident with decreased CBP binding and histone acetylation at promoters of neuronal and glial genes. Inhibition of histone deacetylation rescued these deficits. Moreover, CBP phosphorylation by atypical protein kinase C zeta was necessary for histone acetylation at neural gene promoters and appropriate differentiation. These data support a model in which environmental cues regulate CBP activity and histone acetylation to control neural precursor competency to differentiate, and indicate that cbp haploinsufficiency disrupts this mechanism, thereby likely causing cognitive dysfunction in RTS.
Collapse
Affiliation(s)
- Jing Wang
- Developmental and Stem Cell Biology Program, Hospital for Sick Children, 555 University Ave., Toronto, ON, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Genes, plasticity and mental retardation. Behav Brain Res 2008; 192:88-105. [PMID: 18329113 DOI: 10.1016/j.bbr.2008.01.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 01/16/2008] [Accepted: 01/16/2008] [Indexed: 11/23/2022]
Abstract
Functional and structural plasticity is a fundamental property of the brain involved in diverse processes ranging from brain construction and repair to storage of experiences during lifetime. Our current understanding of different forms of brain plasticity mechanisms has advanced tremendously in the last decades, benefiting from studies of development and memory storage in adulthood and from investigations of diverse diseased conditions. In this review, we focus on the role of mental retardation (MR) genes and show how this developing area of research can enrich our knowledge of the cellular and molecular mechanisms of brain plasticity and cognitive functions, and of the dysfunctional mechanisms underlying MR. We describe two main groups of MR genes; those leading to dysfunctional neurodevelopmental programs and brain malformations, and those which rely on alterations in molecular mechanisms underlying synaptic organization and plasticity. We first explore the role of MR genes in key mechanisms of neurogenesis and neuronal migration during development and in the adult, such as actin and microtubule-cytoskeletal dynamics and signal transduction. We then define the contribution of MR genes to forms of activity-dependent synaptic modifications, such as those involved in molecular organization of the synapse, intracellular signaling regulating gene programs and neuronal cytoskeleton to control network remodeling. We trace the characteristics of MR genes playing key roles in many forms of brain plasticity mechanisms, and highlight specific MR genes that endorse distinct roles in different cell types or brain regions, and at various times of a brain lifetime.
Collapse
|
15
|
Abstract
Rubinstein-Taybi syndrome is characterised by mental retardation, growth retardation and a particular dysmorphology. The syndrome is rare, with a frequency of approximately one affected individual in 100,000 newborns. Mutations in two genes - CREBBP and EP300 - have been identified to cause the syndrome. These two genes show strong homology and encode histone acetyltransferases (HATs), which are transcriptional co-activators involved in many signalling pathways. Loss of HAT activity is sufficient to account for the phenomena seen in Rubinstein-Taybi patients. Although some mutations found in CREBBP are translocations, inversions and large deletions, most are point mutations or small deletions and insertions. Mutations in EP300 are comparatively rare. Extensive screening of patients has revealed mutations in CREBBP and EP300 in around 50% of cases. The cause of the syndrome in the remaining patients remains to be identified, but other genes could also be involved. Here, we describe the clinical presentation of Rubinstein-Taybi syndrome, review the mutation spectrum and discuss the current understanding of causative molecular mechanisms.
Collapse
|
16
|
Vecsey CG, Hawk JD, Lattal KM, Stein JM, Fabian SA, Attner MA, Cabrera SM, McDonough CB, Brindle PK, Abel T, Wood MA. Histone deacetylase inhibitors enhance memory and synaptic plasticity via CREB:CBP-dependent transcriptional activation. J Neurosci 2007; 27:6128-40. [PMID: 17553985 PMCID: PMC2925045 DOI: 10.1523/jneurosci.0296-07.2007] [Citation(s) in RCA: 609] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance both memory and synaptic plasticity. The current model for the action of HDAC inhibitors assumes that they alter gene expression globally and thus affect memory processes in a nonspecific manner. Here, we show that the enhancement of hippocampus-dependent memory and hippocampal synaptic plasticity by HDAC inhibitors is mediated by the transcription factor cAMP response element-binding protein (CREB) and the recruitment of the transcriptional coactivator and histone acetyltransferase CREB-binding protein (CBP) via the CREB-binding domain of CBP. Furthermore, we show that the HDAC inhibitor trichostatin A does not globally alter gene expression but instead increases the expression of specific genes during memory consolidation. Our results suggest that HDAC inhibitors enhance memory processes by the activation of key genes regulated by the CREB:CBP transcriptional complex.
Collapse
Affiliation(s)
| | | | - K. Matthew Lattal
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, Oregon 97239
| | - Joel M. Stein
- Cell and Molecular Biology Graduate Group, University of Pennsylvania 19104
| | | | | | - Sara M. Cabrera
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, California 92697, and
| | | | - Paul K. Brindle
- Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Ted Abel
- Neuroscience Graduate Group
- Department of Biology, and
- Cell and Molecular Biology Graduate Group, University of Pennsylvania 19104
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, Irvine, Irvine, California 92697, and
| |
Collapse
|
17
|
Abstract
During development of the mammalian nervous system, neural stem cells generate neurons first and glia second, thereby allowing the initial establishment of neural circuitry, and subsequent matching of glial numbers and position to that circuitry. Here, we have reviewed work addressing the mechanisms underlying this timed cell genesis, with a particular focus on the developing cortex. These studies have defined an intriguing interplay between intrinsic epigenetic status, transcription factors, and environmental cues, all of which work together to establish this fascinating and complex biological timing mechanism.
Collapse
Affiliation(s)
- Freda D Miller
- Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto M5G 1X8, Canada.
| | | |
Collapse
|
18
|
Barco A. The Rubinstein?Taybi syndrome: modeling mental impairment in the mouse. GENES BRAIN AND BEHAVIOR 2007; 6 Suppl 1:32-9. [PMID: 17543037 DOI: 10.1111/j.1601-183x.2007.00320.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Mental impairment syndromes are diagnosed based on below-average general intellectual function originated during developmental periods. Intellectual abilities rely on the capability of our brain to obtain, process, store and retrieve information. Advances in the past decade on the molecular basis of memory have led to a better understanding of how a normal brain works but also have shed new light on our understanding of many pathologies of the nervous system, including diverse syndromes involving mental impairment. The recent multidisciplinary analysis of various mouse models for Rubinstein-Taybi syndrome has shown the power of animal models to produce an important leap forward in our understanding of a complex mental disease while simultaneously opening new avenues for its treatment. These studies also suggest that some of the cognitive and physiological deficits observed in mental impairment syndromes may not simply be caused by defects originated during development but may result from the continued requirement of specific enzymatic activities throughout life.
Collapse
Affiliation(s)
- A Barco
- Instituto de Neurociencias de Alicante (UMH-CSIC), Campus de Sant Joan, Sant Joan d'Alacant, Spain.
| |
Collapse
|
19
|
Brown RE, Wong AA. The influence of visual ability on learning and memory performance in 13 strains of mice. Learn Mem 2007; 14:134-44. [PMID: 17351136 PMCID: PMC1838554 DOI: 10.1101/lm.473907] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We calculated visual ability in 13 strains of mice (129SI/Sv1mJ, A/J, AKR/J, BALB/cByJ, C3H/HeJ, C57BL/6J, CAST/EiJ, DBA/2J, FVB/NJ, MOLF/EiJ, SJL/J, SM/J, and SPRET/EiJ) on visual detection, pattern discrimination, and visual acuity and tested these and other mice of the same strains in a behavioral test battery that evaluated visuo-spatial learning and memory, conditioned odor preference, and motor learning. Strain differences in visual acuity accounted for a significant proportion of the variance between strains in measures of learning and memory in the Morris water maze. Strain differences in motor learning performance were not influenced by visual ability. Conditioned odor preference was enhanced in mice with visual defects. These results indicate that visual ability must be accounted for when testing for strain differences in learning and memory in mice because differences in performance in many tasks may be due to visual deficits rather than differences in higher order cognitive functions. These results have significant implications for the search for the neural and genetic basis of learning and memory in mice.
Collapse
Affiliation(s)
- Richard E Brown
- Department of Psychology and Neuroscience Institute, Dalhousie University, Halifax, Nova Scotia, Canada.
| | | |
Collapse
|
20
|
Wood MA, Attner MA, Oliveira AM, Brindle PK, Abel T. A transcription factor-binding domain of the coactivator CBP is essential for long-term memory and the expression of specific target genes. Learn Mem 2006; 13:609-17. [PMID: 16980541 PMCID: PMC1783615 DOI: 10.1101/lm.213906] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Transcriptional activation is a key process required for long-term memory formation. Recently, the transcriptional coactivator CREB-binding protein (CBP) was shown to be critical for hippocampus-dependent long-term memory and hippocampal synaptic plasticity. As a coactivator with intrinsic histone acetyltransferase activity, CBP interacts with numerous transcription factors and contains multiple functional domains. Currently, it is not known which transcription factor-binding domain of CBP is essential for memory storage. Using mice that carry inactivating mutations in the CREB-binding (KIX) domain of the coactivator CBP (CBPKIX/KIX mice), we show that the KIX domain is required for long-term memory storage. These results are the first to identify an in vivo function for the KIX domain of CBP in the brain, and they suggest that KIX-interacting transcription factors recruit CBP histone acetyltransferase activity during long-term memory storage. One such KIX-interacting factor is the transcription factor CREB. Using quantitative real-time RT-PCR, we find that the expression of specific CREB target genes is reduced in the hippocampi of CBPKIX/KIX mice during memory consolidation. The recruitment of the transcriptional coactivator CBP via the KIX domain thus imparts target gene-dependent selectivity to CREB-driven transcriptional regulation, thereby activating genes required for the long-term storage of hippocampus-dependent memory.
Collapse
Affiliation(s)
- Marcelo A. Wood
- Department of Neurobiology & Behavior, Center for the Neurobiology of Learning & Memory, University of California at Irvine, Irvine, California 92697, USA
- Corresponding authors.E-mail ; fax (949) 824-6633;E-mail ; fax (215) 898-8780
| | - Michelle A. Attner
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Ana M.M. Oliveira
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Paul K. Brindle
- Department of Biochemistry, St. Jude Children’s Research Hospital, Memphis, Tennessee 38105, USA
| | - Ted Abel
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Corresponding authors.E-mail ; fax (949) 824-6633;E-mail ; fax (215) 898-8780
| |
Collapse
|
21
|
Wood MA, Hawk JD, Abel T. Combinatorial chromatin modifications and memory storage: a code for memory? Learn Mem 2006; 13:241-4. [PMID: 16741277 PMCID: PMC2909467 DOI: 10.1101/lm.278206] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Marcelo A. Wood
- Department of Neurobiology and Behavior, University of California, Irvine, California 92697, USA
- Corresponding authors. ; fax (949) 824-8439
| | - Joshua D. Hawk
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Ted Abel
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- ; fax (215) 898-8780
| |
Collapse
|
22
|
Oliveira AMM, Abel T, Brindle PK, Wood MA. Differential role for CBP and p300 CREB-binding domain in motor skill learning. Behav Neurosci 2006; 120:724-9. [PMID: 16768624 DOI: 10.1037/0735-7044.120.3.724] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cyclic adenosine monophosphate response element binding protein (CREB) binding protein (CBP) and E1A binding protein (p300) are highly homologous transcriptional coactivators with histone acetyltransferase activity. Although CBP and p300 have unique functions in vivo during embryogenesis and hematopoiesis, their functions within the nervous system remain poorly understood. The authors demonstrate that these coactivators have differential roles in motor skill learning. Mice with a mutation in the CREB-binding (KIX) domain of CBP exhibited motor learning deficits. However, mice with the analogous mutation in the KIX domain of p300 showed normal motor learning. Further, CREB knock-out mice exhibited a motor learning deficit similar to that of CBP-KIX mutant mice. These results suggest that the CREB-CBP interaction is more limiting or critical than the CREB-p300 interaction for motor skill learning. Thus, CBP and p300 are genetically distinct at the behavioral level.
Collapse
Affiliation(s)
- Ana M M Oliveira
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | | |
Collapse
|