Examinando por Autor "Ondaro Ezkurra, Jon"

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    Altered tubulin detyrosination due to SVBP malfunction induces cytokinesis failure and senescence, underlying a complex hereditary spastic paraplegia
    (John Wiley and Sons Inc, 2025-01) Launay, Nathalie; Espinosa Alcantud, Maria Dolores; Verdura, Edgar; Fernández García de Eulate, Gorka; Ondaro Ezkurra, Jon; Iruzubieta Agudo, Pablo; Marsal Terés, María; Schlüter, Agatha; Ruiz Sales, Montserrat; Fourcade, Stèphane; Rodríguez-Palmero Seuma, Agustí; Zulaica, Miren; Sistiaga Berrondo, Andone; Labayru, Garazi; Loza-Alvarez, Pablo; Vaquero, Alejandro; López de Munain Arregui, Adolfo; Pujol, Aurora
    Senescence, marked by permanent cell cycle arrest may contribute to the decline in regenerative potential and neuronal function, thereby promoting neurodegenerative disorders. In this study, we employed whole exome sequencing to identify a previously unreported biallelic missense variant in SVBP (p.Leu49Pro) in six patients from three unrelated families. These affected individuals present with a complex hereditary spastic paraplegia (HSP), peripheral neuropathy, verbal apraxia, and intellectual disability, exhibiting a milder phenotype compared to patients with nonsense SVBP mutations described previously. Consistent with SVBP's primary role as a chaperone necessary for VASH-mediated tubulin detyrosination, both patient fibroblasts with the p.Leu49Pro mutation, and HeLa cells harboring an SVBP knockdown exhibit microtubule dynamic instability and alterations in pericentriolar material (PCM) component trafficking and centrosome cohesion. In patient fibroblasts, structural abnormalities in the centrosome trigger mitotic errors and cellular senescence. Notably, premature senescence characterized by elevated levels of p16INK4, was also observed in patient peripheral blood mononuclear cells (PBMCs). Taken together, our findings underscore the critical role of SVBP in the development and maintenance of the central nervous system, providing novel insights associating cytokinesis failure with cortical motor neuron disease and intellectual disability.
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    Ítem
    Dysregulated FOXO1 activity drives skeletal muscle intrinsic dysfunction in amyotrophic lateral sclerosis
    (Springer Science and Business Media Deutschland GmbH, 2024-09-16) Zufiría García, Mónica; Pikatza-Menoio, Oihane; Garciandia Arcelus, Maddi; Bengoetxea Bausela, Xabier; Jiménez Zúñiga, Andrés; Elicegui, Amaia; Levchuk, María; Arnold García, Olatz; Ondaro Ezkurra, Jon; Iruzubieta Agudo, Pablo; Rodríguez Gómez, Laura; Fernández Pelayo, Uxoa; Muñoz Oreja, Mikel; Aiastui Pujana, Ana; García Verdugo, Jose Manuel; Herranz Pérez, Vicente; Zulaica, Miren; Poza Aldea, Juan José; Ruiz Onandi, Rebeca; Fernández Torrón, Roberto; Espinal Valencia, Juan Bautista; Bonilla Zagala, Mario; Lersundi Artamendi, Ana; Fernández-Eulate, Gorka; Riancho Zarrabeitia, Javier; Vallejo Illarramendi, Ainara; Holt, Ian James; Sáenz, Amets; Malfatti, Edoardo; Duguez, Stéphanie; Blázquez García, Lorea; López de Munain Arregui, Adolfo; Gereñu Lopetegi, Gorka; Gil Bea, Francisco Javier; Alonso-Martin, Sonia
    Amyotrophic Lateral Sclerosis (ALS) is a multisystemic neurodegenerative disorder, with accumulating evidence indicating metabolic disruptions in the skeletal muscle preceding disease symptoms, rather than them manifesting as a secondary consequence of motor neuron (MN) degeneration. Hence, energy homeostasis is deeply implicated in the complex physiopathology of ALS and skeletal muscle has emerged as a key therapeutic target. Here, we describe intrinsic abnormalities in ALS skeletal muscle, both in patient-derived muscle cells and in muscle cell lines with genetic knockdown of genes related to familial ALS, such as TARDBP (TDP-43) and FUS. We found a functional impairment of myogenesis that parallels defects of glucose oxidation in ALS muscle cells. We identified FOXO1 transcription factor as a key mediator of these metabolic and functional features in ALS muscle, via gene expression profiling and biochemical surveys in TDP-43 and FUS-silenced muscle progenitors. Strikingly, inhibition of FOXO1 mitigated the impaired myogenesis in both the genetically modified and the primary ALS myoblasts. In addition, specific in vivo conditional knockdown of TDP-43 or FUS orthologs (TBPH or caz) in Drosophila muscle precursor cells resulted in decreased innervation and profound dysfunction of motor nerve terminals and neuromuscular synapses, accompanied by motor abnormalities and reduced lifespan. Remarkably, these phenotypes were partially corrected by foxo inhibition, bolstering the potential pharmacological management of muscle intrinsic abnormalities associated with ALS. The findings demonstrate an intrinsic muscle dysfunction in ALS, which can be modulated by targeting FOXO factors, paving the way for novel therapeutic approaches that focus on the skeletal muscle as complementary target tissue.