Examinando por Autor "Jury, Nur"

Mostrando 1 - 3 de 3
  • Miniatura
    Ítem
    Epigenetic editing of the Dlg4/PSD95 gene improves cognition in aged and Alzheimer's disease mice
    (BRAIA, 2017-12) Bustos, Fernando J.; Ampuero, Estibaliz; Jury, Nur; Aguilar, Rodrigo; Falahi, Fahimeh; Toledo, Jorge; Ahumada, Juan; Lata, Jaclyn; Cubillos, Paula; Henríquez, Berta; Guerra, Miguel V.; Stehberg, Jimmy; Neve, Rachael L.; Inestrosa, Nibaldo C.; Wyneken, Ursula; Fuenzalida, Marco; Härtel, Steffen; Sena-Esteves, Miguel; Varela-Nallar, Lorena; Rots, Marianne G.; Montecino, Martin; Van Zundert, Brigitte
    The Dlg4 gene encodes for post-synaptic density protein 95 (PSD95), a major synaptic protein that clusters glutamate receptors and is critical for plasticity. PSD95 levels are diminished in ageing and neurodegenerative disorders, including Alzheimer's disease and Huntington's disease. The epigenetic mechanisms that (dys)regulate transcription of Dlg4/PSD95, or other plasticity genes, are largely unknown, limiting the development of targeted epigenome therapy. We analysed the Dlg4/PSD95 epigenetic landscape in hippocampal tissue and designed a Dlg4/PSD95 gene-targeting strategy: a Dlg4/PSD95 zinc finger DNA-binding domain was engineered and fused to effector domains to either repress (G9a, Suvdel76, SKD) or activate (VP64) transcription, generating artificial transcription factors or epigenetic editors (methylating H3K9). These epi-editors altered critical histone marks and subsequently Dlg4/PSD95 expression, which, importantly, impacted several hippocampal neuron plasticity processes. Intriguingly, transduction of the artificial transcription factor PSD95-VP64 rescued memory deficits in aged and Alzheimer's disease mice. Conclusively, this work validates PSD95 as a key player in memory and establishes epigenetic editing as a potential therapy to treat human neurological disorders. © 2017 The Author. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved.
  • No hay miniatura disponible
    Ítem
    Excessive release of inorganic polyphosphate by ALS/FTD astrocytes causes non-cell-autonomous toxicity to motoneurons
    (Cell Press, 2022-05-18) Arredondo, Cristian; Cefaliello, Carolina; Dyrda, Agnieszka; Jury, Nur; Martinez, Pablo; Díaz, Iván; Amaro, Armando; Tran, Helene; Morales, Danna; Pertusa, Maria; Stoica, Lorelei; Fritz, Elsa; Corvalán, Daniela; Abarzúa, Sebastián; Méndez-Ruette, Maxs; Fernández, Paola; Rojas, Fabiola; Kumar, Meenakshi Sundaram; Aguilar, Rodrigo; Almeida, Sandra; Weiss, Alexandra; Bustos, Fernando J.; González-Nilo, Fernando; Otero, Carolina; Tevy, Maria Florencia; Bosco, Daryl A.; Sáez, Juan C.; Kähne, Thilo; Gao, Fen-Biao; Berry, James D.; Nicholson, Katharine; Sena-Esteves, Miguel; Madrid, Rodolfo; Varela, Diego; Montecino, Martin; Brown, Robert H.; van Zundert, Brigitte
    Non-cell-autonomous mechanisms contribute to neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), in which astrocytes release unidentified factors that are toxic to motoneurons (MNs). We report here that mouse and patient iPSC-derived astrocytes with diverse ALS/FTD-linked mutations (SOD1, TARDBP, and C9ORF72) display elevated levels of intracellular inorganic polyphosphate (polyP), a ubiquitous, negatively charged biopolymer. PolyP levels are also increased in astrocyte-conditioned media (ACM) from ALS/FTD astrocytes. ACM-mediated MN death is prevented by degrading or neutralizing polyP in ALS/FTD astrocytes or ACM. Studies further reveal that postmortem familial and sporadic ALS spinal cord sections display enriched polyP staining signals and that ALS cerebrospinal fluid (CSF) exhibits increased polyP concentrations. Our in vitro results establish excessive astrocyte-derived polyP as a critical factor in non-cell-autonomous MN degeneration and a potential therapeutic target for ALS/FTD. The CSF data indicate that polyP might serve as a new biomarker for ALS/FTD. © 2022 Elsevier Inc.
  • Miniatura
    Ítem
    Widespread loss of the silencing epigenetic mark H3K9me3 in astrocytes and neurons along with hippocampal-dependent cognitive impairment in C9orf72 BAC transgenic mice
    (BioMed Central Ltd., 2020-02) Jury, Nur; Abarzua, Sebastian; Diaz, Ivan; . Guerra, Miguel V; Ampuero, Estibaliz; Cubillos, Paula; Martinez, Pablo; Herrera-Soto, Andrea; Arredondo, Cristian; Rojas, Fabiola; Manterola, Marcia; Rojas, Adriana; Montecino, Martín; Varela-Nallar, Lorena; Brigitte, van Zundert
    Background: Hexanucleotide repeat expansions of the G4C2 motif in a non-coding region of the C9ORF72 gene are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Tissues from C9ALS/FTD patients and from mouse models of ALS show RNA foci, dipeptide-repeat proteins, and notably, widespread alterations in the transcriptome. Epigenetic processes regulate gene expression without changing DNA sequences and therefore could account for the altered transcriptome profiles in C9ALS/FTD; here, we explore whether the critical repressive marks H3K9me2 and H3K9me3 are altered in a recently developed C9ALS/FTD BAC mouse model (C9BAC). Results: Chromocenters that constitute pericentric constitutive heterochromatin were visualized as DAPI- or Nucblue-dense foci in nuclei. Cultured C9BAC astrocytes exhibited a reduced staining signal for H3K9me3 (but not for H3K9me2) at chromocenters that was accompanied by a marked decline in the global nuclear level of this mark. Similar depletion of H3K9me3 at chromocenters was detected in astrocytes and neurons of the spinal cord, motor cortex, and hippocampus of C9BAC mice. The alterations of H3K9me3 in the hippocampus of C9BAC mice led us to identify previously undetected neuronal loss in CA1, CA3, and dentate gyrus, as well as hippocampal-dependent cognitive deficits. Conclusions: Our data indicate that a loss of the repressive mark H3K9me3 in astrocytes and neurons in the central nervous system of C9BAC mice represents a signature during neurodegeneration and memory deficit of C9ALS/FTD. © 2020 The Author(s).