Journal of Molecular Biology

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  • A Fibrin-Specific Monoclonal Antibody from a Designed Phage Display Library Inhibits Clot Formation and Localizes to Tumors In Vivo
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Alessia Putelli , Jonathan D. Kiefer , Matthias Zadory , Mattia Matasci , Dario Neri

    Fibrin formation from fibrinogen is a rare process in the healthy organism but is a pathological feature of thrombotic events, cancer and a wide range of inflammatory conditions. We have designed and constructed an antibody phage display library (containing 13 billion clones) for the selective recognition of the N-terminal peptide of fibrin alpha chain. The key structural feature for selective fibrin binding was a K94E mutation in the VH domain. From this library, an antibody was isolated (termed AP2), which recognizes the five N-terminal amino acids of fibrin with high affinity (K d =44nM), but does not bind to fibrinogen. The AP2 antibody could be expressed in various formats (scFv, small immune protein and IgG) and inhibited fibrin clot formation in a concentration-dependent manner. Moreover, the AP2 antibody stained the fibrin-rich provisional stroma in solid tumors but did not exhibit any detectable staining toward normal tissues. Using a radioiodinated antibody preparation and quantitative biodistribution studies in tumor-bearing mice, AP2 was shown to selectively localize to fibrin-rich F9 murine teratocarcinomas, but not to SKRC-52 human kidney cancer xenografts. Collectively, the experiments indicate that the AP2 antibody recognizes fibrin in vitro and in vivo. The antibody may facilitate the development of fibrin-specific therapeutic agents.
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  • Coevolution of Specificity Determinants in Eukaryotic Glutamyl- and Glutaminyl-tRNA Synthetases
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Andrew Hadd , John J. Perona

    The glutaminyl-tRNA synthetase (GlnRS) enzyme, which pairs glutamine with tRNAGln for protein synthesis, evolved by gene duplication in early eukaryotes from a nondiscriminating glutamyl-tRNA synthetase (GluRS) that aminoacylates both tRNAGln and tRNAGlu with glutamate. This ancient GluRS also separately differentiated to exclude tRNAGln as a substrate, and the resulting discriminating GluRS and GlnRS further acquired additional protein domains assisting function in cis (the GlnRS N-terminal Yqey domain) or in trans (the Arc1p protein associating with GluRS). These added domains are absent in contemporary bacterial GlnRS and GluRS. Here, using Saccharomyces cerevisiae enzymes as models, we find that the eukaryote-specific protein domains substantially influence amino acid binding, tRNA binding and aminoacylation efficiency, but they play no role in either specific nucleotide readout or discrimination against noncognate tRNA. Eukaryotic tRNAGln and tRNAGlu recognition determinants are found in equivalent positions and are mutually exclusive to a significant degree, with key nucleotides located adjacent to portions of the protein structure that differentiated during the evolution of archaeal nondiscriminating GluRS to GlnRS. These findings provide important corroboration for the evolutionary model and suggest that the added eukaryotic domains arose in response to distinctive selective pressures associated with the greater complexity of the eukaryotic translational apparatus. We also find that the affinity of GluRS for glutamate is significantly increased when Arc1p is not associated with the enzyme. This is consistent with the lower concentration of intracellular glutamate and the dissociation of the Arc1p:GluRS complex upon the diauxic shift to respiratory conditions.
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  • Crystal Structure of a Symmetric Football-Shaped GroEL:GroES2-ATP14 Complex Determined at 3.8Å Reveals Rearrangement between Two GroEL Rings
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Ayumi Koike-Takeshita , Takatoshi Arakawa , Hideki Taguchi , Tatsuro Shimamura

    The chaperonin GroEL is an essential chaperone that assists in protein folding with the aid of GroES and ATP. GroEL forms a double-ring structure, and both rings can bind GroES in the presence of ATP. Recent progress on the GroEL mechanism has revealed the importance of a symmetric 1:2 GroEL:GroES2 complex (the “football”-shaped complex) as a critical intermediate during the functional GroEL cycle. We determined the crystal structure of the football GroEL:GroES2-ATP14 complex from Escherichia coli at 3.8Å, using a GroEL mutant that is extremely defective in ATP hydrolysis. The overall structure of the football complex resembled the GroES-bound GroEL ring of the asymmetric 1:1 GroEL:GroES complex (the “bullet” complex). However, the two GroES-bound GroEL rings form a modified interface by an ~7° rotation about the 7-fold axis. As a result, the inter-ring contacts between the two GroEL rings in the football complex differed from those in the bullet complex. The differences provide a structural basis for the apparently impaired inter-ring negative cooperativity observed in several biochemical analyses.
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  • Functional Suppression of HAMP Domain Signaling Defects in the E. coli Serine Chemoreceptor
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Run-Zhi Lai , John S. Parkinson

    HAMP domains play key signaling roles in many bacterial receptor proteins. The four-helix HAMP bundle of the homodimeric Escherichia coli serine chemoreceptor (Tsr) interacts with an adjoining four-helix sensory adaptation bundle to regulate the histidine autokinase CheA bound to the cytoplasmic tip of the Tsr molecule. The adaptation helices undergo reversible covalent modifications that tune the stimulus-responsive range of the receptor: unmodified E residues promote kinase-off output, and methylated E residues or Q replacements at modification sites promote kinase-on output. We used mutationally imposed adaptational modification states and cells with various combinations of the sensory adaptation enzymes, CheR and CheB, to characterize the signaling properties of mutant Tsr receptors that had amino acid replacements in packing layer 3 of the HAMP bundle and followed in vivo CheA activity with an assay based on Förster resonance energy transfer. We found that an alanine or a serine replacement at HAMP residue I229 effectively locked Tsr output in a kinase-on state, abrogating chemotactic responses. A second amino acid replacement in the same HAMP packing layer alleviated the I229A and I229S signaling defects. Receptors with the suppressor changes alone mediated chemotaxis in adaptation-proficient cells but exhibited altered sensitivity to serine stimuli. Two of the suppressors (S255E and S255A) shifted Tsr output toward the kinase-off state, but two others (S255G and L256F) shifted output toward a kinase-on state. The alleviation of locked-on defects by on-shifted suppressors implies that Tsr-HAMP has several conformationally distinct kinase-active output states and that HAMP signaling might involve dynamic shifts over a range of bundle conformations.
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  • A Conserved Isoleucine Maintains the Inactive State of Bruton's Tyrosine Kinase
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Scott E. Boyken , Nikita Chopra , Qian Xie , Raji E. Joseph , Thomas E. Wales , D. Bruce Fulton , John R. Engen , Robert L. Jernigan , Amy H. Andreotti

    Despite high level of homology among non-receptor tyrosine kinases, different kinase families employ a diverse array of regulatory mechanisms. For example, the catalytic kinase domains of the Tec family kinases are inactive without assembly of the adjacent regulatory domains, whereas the Src kinase domains are autoinhibited by the assembly of similar adjacent regulatory domains. Using molecular dynamics simulations, biochemical assays, and biophysical approaches, we have uncovered an isoleucine residue in the kinase domain of the Tec family member Btk that, when mutated to the closely related leucine, leads to a shift in the conformational equilibrium of the kinase domain toward the active state. The single amino acid mutation results in measureable catalytic activity for the Btk kinase domain in the absence of the regulatory domains. We suggest that this isoleucine side chain in the Tec family kinases acts as a “wedge” that restricts the conformational space available to key regions in the kinase domain, preventing activation until the kinase domain associates with its regulatory subunits and overcomes the energetic barrier to activation imposed by the isoleucine side chain.
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  • Characterization of Membrane Protein Interactions by Isothermal Titration Calorimetry
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Alan J. Situ , Thomas Schmidt , Parichita Mazumder , Tobias S. Ulmer

    Understanding the structure, folding, and interaction of membrane proteins requires experimental tools to quantify the association of transmembrane (TM) helices. Here, we introduce isothermal titration calorimetry (ITC) to measure integrin αIIbβ3 TM complex affinity, to study the consequences of helix–helix preorientation in lipid bilayers, and to examine protein-induced lipid reorganization. Phospholipid bicelles served as membrane mimics. The association of αIIbβ3 proceeded with a free energy change of −4.61±0.04kcal/mol at bicelle conditions where the sampling of random helix–helix orientations leads to complex formation. At bicelle conditions that approach a true bilayer structure in effect, an entropy saving of >1kcal/mol was obtained from helix–helix preorientation. The magnitudes of enthalpy and entropy changes increased distinctly with bicelle dimensions, indicating long-range changes in bicelle lipid properties upon αIIbβ3 TM association. NMR spectroscopy confirmed ITC affinity measurements and revealed αIIbβ3 association and dissociation rates of 4500±100s−1 and 2.1±0.1s−1, respectively. Thus, ITC is able to provide comprehensive insight into the interaction of membrane proteins.
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  • Erratum for “Structural Insights into the Substrate Specificity of (S)-Ureidoglycolate Amidohydrolase and Its Comparison with Allantoate Amidohydrolase” [J. Mol. Biol. 426 (2014) 3028–3040]
    [Oct 2014]

    Publication date: 23 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 21

    Author(s): Inchul Shin , Kitae Han , Sangkee Rhee







    Categories: Journal Articles
  • Editorial Board
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20









    Categories: Journal Articles
  • Contents List
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20









    Categories: Journal Articles
  • Zooming into Epigenetic Regulatory Elements in Health and Disease
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Sepideh Khorasanizadeh , Marina Ostankovitch







    Categories: Journal Articles
  • Chromatin Structure and Replication Origins: Determinants of Chromosome Replication and Nuclear Organization
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Owen K. Smith , Mirit I. Aladjem

    The DNA replication program is, in part, determined by the epigenetic landscape that governs local chromosome architecture and directs chromosome duplication. Replication must coordinate with other biochemical processes occurring concomitantly on chromatin, such as transcription and remodeling, to insure accurate duplication of both genetic and epigenetic features and to preserve genomic stability. The importance of genome architecture and chromatin looping in coordinating cellular processes on chromatin is illustrated by two recent sets of discoveries. First, chromatin-associated proteins that are not part of the core replication machinery were shown to affect the timing of DNA replication. These chromatin-associated proteins could be working in concert, or perhaps in competition, with the transcriptional machinery and with chromatin modifiers to determine the spatial and temporal organization of replication initiation events. Second, epigenetic interactions are mediated by DNA sequences that determine chromosomal replication. In this review, we summarize recent findings and current models linking spatial and temporal regulation of the replication program with epigenetic signaling. We discuss these issues in the context of the genome's three-dimensional structure with an emphasis on events occurring during the initiation of DNA replication.
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  • Genome-Scale Acetylation-Dependent Histone Eviction during Spermatogenesis
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Afsaneh Goudarzi , Hitoshi Shiota , Sophie Rousseaux , Saadi Khochbin

    A genome-wide histone hyperacetylation is known to occur in the absence of transcription in haploid male germ cells, spermatids, before and during the global histone eviction and their replacement by non-histone DNA-packaging proteins. Although the occurrence of this histone hyperacetylation has been correlated with histone removal for a long time, the underlying mechanisms have remained largely obscure. Important recent discoveries have not only shed light on how histone acetylation could drive a subsequent transformation in genome organization but also revealed that the associated nucleosome dismantlement is a multi-step process, requiring the contribution of histone variants, critical destabilizing histone modifications and chromatin readers, including Brdt, working together to achieve the full packaging of the male genome, indispensable for the propagation of life.
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  • Emerging Technologies to Map the Protein Methylome
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Scott M. Carlson , Or Gozani

    Protein methylation plays an integral role in cellular signaling, most notably by modulating proteins bound at chromatin and increasingly through regulation of non-histone proteins. One central challenge in understanding how methylation acts in signaling is identifying and measuring protein methylation. This includes locus-specific modification of histones, on individual non-histone proteins, and globally across the proteome. Protein methylation has been studied traditionally using candidate approaches such as methylation-specific antibodies, mapping of post-translational modifications by mass spectrometry, and radioactive labeling to characterize methylation on target proteins. Recent developments have provided new approaches to identify methylated proteins, measure methylation levels, identify substrates of methyltransferase enzymes, and match methylated proteins to methyl-specific reader domains. Methyl-binding protein domains and improved antibodies with broad specificity for methylated proteins are being used to characterize the “protein methylome”. They also have the potential to be used in high-throughput assays for inhibitor screens and drug development. These tools are often coupled to improvements in mass spectrometry to quickly identify methylated residues, as well as to protein microarrays, where they can be used to screen for methylated proteins. Finally, new chemical biology strategies are being used to probe the function of methyltransferases, demethylases, and methyl-binding “reader” domains. These tools create a “system-level” understanding of protein methylation and integrate protein methylation into broader signaling processes.
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  • Keeping Them All Together: β-Propeller Domains in Histone Methyltransferase Complexes
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Elisa Bergamin , Alexandre Blais , Jean-François Couture

    Histone methyltransferases (HKMTs) residing in multi-subunit protein complexes frequently require the presence of β-propeller proteins to achieve their biological functions. Recent biochemical studies have highlighted the functional diversity of these scaffolding proteins in maintaining the integrity of the complexes, allosterically regulating HKMT enzymatic activity and acting as “histone tethering devices” to facilitate the interaction between HKMTs and their substrates. Structural studies have revealed that, while β-propeller domain proteins share structural similarity, they employ divergent mechanisms to achieve their functions. This review focuses on the progress made in the last decade to identify the biochemical determinants underlying the functions of these important proteins.
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  • Chromatin Regulation of DNA Damage Repair and Genome Integrity in the Central Nervous System
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Ling Pan , Jay Penney , Li-Huei Tsai

    With the continued extension of lifespan, aging and age-related diseases have become a major medical challenge to our society. Aging is accompanied by changes in multiple systems. Among these, the aging process in the central nervous system is critically important but very poorly understood. Neurons, as post-mitotic cells, are devoid of replicative associated aging processes, such as senescence and telomere shortening. However, because of the inability to self-replenish, neurons have to withstand challenge from numerous stressors over their lifetime. Many of these stressors can lead to damage of the neurons' DNA. When the accumulation of DNA damage exceeds a neuron's capacity for repair, or when there are deficiencies in DNA repair machinery, genome instability can manifest. The increased mutation load associated with genome instability can lead to neuronal dysfunction and ultimately to neuron degeneration. In this review, we first briefly introduce the sources and types of DNA damage and the relevant repair pathways in the nervous system (summarized in Fig. 1). We then discuss the chromatin regulation of these processes and summarize our understanding of the contribution of genomic instability to neurodegenerative diseases.
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  • Epigenetic Signaling in Psychiatric Disorders
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Catherine J. Peña , Rosemary C. Bagot , Benoit Labonté , Eric J. Nestler

    Psychiatric disorders are complex multifactorial illnesses involving chronic alterations in neural circuit structure and function. While genetic factors are important in the etiology of disorders such as depression and addiction, relatively high rates of discordance among identical twins clearly indicate the importance of additional mechanisms. Environmental factors such as stress or prior drug exposure are known to play a role in the onset of these illnesses. Such exposure to environmental insults induces stable changes in gene expression, neural circuit function, and ultimately behavior, and these maladaptations appear distinct between developmental and adult exposures. Increasing evidence indicates that these sustained abnormalities are maintained by epigenetic modifications in specific brain regions. Indeed, transcriptional dysregulation and associated aberrant epigenetic regulation is a unifying theme in psychiatric disorders. Aspects of depression and addiction can be modeled in animals by inducing disease-like states through environmental manipulations (e.g., chronic stress, drug administration). Understanding how environmental factors recruit the epigenetic machinery in animal models reveals new insight into disease mechanisms in humans.
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  • Structural Insights into Estrogen Receptor α Methylation by Histone Methyltransferase SMYD2, a Cellular Event Implicated in Estrogen Signaling Regulation
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Yuanyuan Jiang , Laura Trescott , Joshua Holcomb , Xi Zhang , Joseph Brunzelle , Nualpun Sirinupong , Xiaobing Shi , Zhe Yang

    Estrogen receptor (ER) signaling plays a pivotal role in many developmental processes and has been implicated in numerous diseases including cancers. We recently showed that direct ERα methylation by the multi-specificity histone lysine methyltransferase SMYD2 regulates estrogen signaling through repressing ERα-dependent transactivation. However, the mechanism controlling the specificity of the SMYD2–ERα interaction and the structural basis of SMYD2 substrate binding diversity are unknown. Here we present the crystal structure of SMYD2 in complex with a target lysine (Lys266)-containing ERα peptide. The structure reveals that ERα binds SMYD2 in a U-shaped conformation with the binding specificity determined mainly by residues C-terminal to the target lysine. The structure also reveals numerous intrapeptide contacts that ensure shape complementarity between the substrate and the active site of the enzyme, thereby likely serving as an additional structural determinant of substrate specificity. In addition, comparison of the SMYD2–ERα and SMYD2–p53 structures provides the first structural insight into the diverse nature of SMYD2 substrate recognition and suggests that the broad specificity of SMYD2 is achieved by multiple molecular mechanisms such as distinct peptide binding modes and the intrinsic dynamics of peptide ligands. Strikingly, a novel potentially SMYD2-specific polyethylene glycol binding site is identified in the CTD domain, implicating possible functions in extended substrate binding or protein–protein interactions. Our study thus provides the structural basis for the SMYD2-mediated ERα methylation, and the resulting knowledge of SMYD2 substrate specificity and target binding diversity could have important implications in selective drug design against a wide range of ERα-related diseases.
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  • Histone Methyltransferase EZH2 Is Transcriptionally Induced by Estradiol as Well as Estrogenic Endocrine Disruptors Bisphenol-A and Diethylstilbestrol
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Arunoday Bhan , Imran Hussain , Khairul I. Ansari , Samara A.M. Bobzean , Linda I. Perrotti , Subhrangsu S. Mandal

    Enhancer of Zeste homolog 2 (EZH2), a methyltransferase specific to histone 3 lysine 27, is a critical player in gene silencing and is overexpressed in breast cancer. Our studies demonstrate that EZH2 is transcriptionally induced by estradiol in cultured breast cancer cells and in the mammary glands of ovariectomized rats. EZH2 promoter contains multiple functional estrogen-response elements. Estrogen receptors (ERs) and ER coregulators such as mixed lineage leukemia (MLL) histone methylases (MLL2 and MLL3) and histone acetyltransferase CBP/P300 bind to the EZH2 promoter in the presence of estradiol and regulate estradiol-induced EZH2 expression. EZH2 expression is also increased upon exposure to estrogenic endocrine disrupting chemicals (EDCs) such as bisphenol-A (BPA) and diethylstilbestrol (DES). Similar to estradiol, BPA and DES-induced EZH2 expression is coordinated by ERs, MLLs and CBP/P300. In summary, we demonstrate that EZH2 is transcriptionally regulated by estradiol in vitro and in vivo, and its expression is potentially dysregulated upon exposure to estrogenic EDCs.
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  • Molecular Basis for the Antiparasitic Activity of a Mercaptoacetamide Derivative That Inhibits Histone Deacetylase 8 (HDAC8) from the Human Pathogen Schistosoma mansoni
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Diana A. Stolfa , Martin Marek , Julien Lancelot , Alexander-Thomas Hauser , Alexandra Walter , Emeline Leproult , Jelena Melesina , Tobias Rumpf , Jean-Marie Wurtz , Jean Cavarelli , Wolfgang Sippl , Raymond J. Pierce , Christophe Romier , Manfred Jung

    Schistosomiasis, caused by the parasitic flatworm Schistosoma mansoni and related species, is a tropical disease that affects over 200 million people worldwide. A new approach for targeting eukaryotic parasites is to tackle their dynamic epigenetic machinery that is necessary for the extensive phenotypic changes during the life cycle of the parasite. Recently, we identified S. mansoni histone deacetylase 8 (smHDAC8) as a potential target for antiparasitic therapy. Here, we present results on the investigations of a focused set of HDAC (histone deacetylase) inhibitors on smHDAC8. Besides several active hydroxamates, we identified a thiol-based inhibitor that inhibited smHDAC8 activity in the micromolar range with unexpected selectivity over the human isotype, which has not been observed so far. The crystal structure of smHDAC8 complexed with the thiol derivative revealed that the inhibitor is accommodated in the catalytic pocket, where it interacts with both the catalytic zinc ion and the essential catalytic tyrosine (Y341) residue via its mercaptoacetamide warhead. To our knowledge, this is the first complex crystal structure of any HDAC inhibited by a mercaptoacetamide inhibitor, and therefore, this finding offers a rationale for further improvement. Finally, an ester prodrug of the thiol HDAC inhibitor exhibited antiparasitic activity on cultured schistosomes in a dose-dependent manner.
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  • The Gene Silencing Transcription Factor REST Represses miR-132 Expression in Hippocampal Neurons Destined to Die
    [Oct 2014]

    Publication date: 9 October 2014
    Source:Journal of Molecular Biology, Volume 426, Issue 20

    Author(s): Jee-Yeon Hwang , Naoki Kaneko , Kyung-Min Noh , Fabrizio Pontarelli , R. Suzanne Zukin

    The gene silencing transcription factor REST [repressor element 1 silencing transcription factor]/NRSF (neuron-restrictive silencer factor) actively represses a large array of coding and noncoding neuron-specific genes important to synaptic plasticity including miR-132. miR-132 is a neuron-specific microRNA and plays a pivotal role in synaptogenesis, synaptic plasticity and structural remodeling. However, a role for miR-132 in neuronal death is not, as yet, well-delineated. Here we show that ischemic insults promote REST binding and epigenetic remodeling at the miR-132 promoter and silencing of miR-132 expression in selectively vulnerable hippocampal CA1 neurons. REST occupancy was not altered at the miR-9 or miR-124a promoters despite the presence of repressor element 1 sites, indicating REST target specificity. Ischemia induced a substantial decrease in two marks of active gene transcription, dimethylation of lysine 4 on core histone 3 (H3K4me2) and acetylation of lysine 9 on H3 (H3K9ac) at the miR-132 promoter. RNAi-mediated depletion of REST in vivo blocked ischemia-induced loss of miR-132 in insulted hippocampal neurons, consistent with a causal relation between activation of REST and silencing of miR-132. Overexpression of miR-132 in primary cultures of hippocampal neurons or delivered directly into the CA1 of living rats by means of the lentiviral expression system prior to induction of ischemia afforded robust protection against ischemia-induced neuronal death. These findings document a previously unappreciated role for REST-dependent repression of miR-132 in the neuronal death associated with global ischemia and identify a novel therapeutic target for amelioration of the neurodegeneration and cognitive deficits associated with ischemic stroke.
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    Categories: Journal Articles