title: Altered Machinery of Protein Synthesis in Alzheimer's: From the Nucleolus to the Ribosome.
abstract: Ribosomes and protein synthesis have been reported to be altered in the cerebral cortex at advanced stages of Alzheimer's disease (AD). Modifications in the hippocampus with disease progression have not been assessed. Sixty-seven cases including middle-aged (MA) and AD stages I-VI were analyzed. Nucleolar chaperones nucleolin, nucleophosmin and nucleoplasmin 3, and upstream binding transcription factor RNA polymerase I gene (UBTF) mRNAs are abnormally regulated and their protein levels reduced in AD. Histone modifications dimethylated histone H3K9 (H3K9me2) and acetylated histone H3K12 (H3K12ac) are decreased in CA1. Nuclear tau declines in CA1 and dentate gyrus (DG), and practically disappears in neurons with neurofibrillary tangles. Subunit 28 ribosomal RNA (28S rRNA) expression is altered in CA1 and DG in AD. Several genes encoding ribosomal proteins are abnormally regulated and protein levels of translation initiation factors eIF2α, eIF3η and eIF5, and elongation factor eEF2, are altered in the CA1 region in AD. These findings show alterations in the protein synthesis machinery in AD involving the nucleolus, nucleus and ribosomes in the hippocampus in AD some of them starting at first stages (I-II) preceding neuron loss. These changes may lie behind reduced numbers of dendritic branches and reduced synapses of CA1 and DG neurons which cause hippocampal atrophy.
authors.affiliation: Institute of Neuropathology, Service of Pathologic Anatomy, IDIBELL-Bellvitge University Hospital, University of Barcelona, Hospitalet de Llobregat, Spain.|Neuropathology, CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Madrid, Spain.
authors.forename: Karina
authors.initials: K
authors.lastname: Hernández-Ortega
authors.affiliation: Institute of Neuropathology, Service of Pathologic Anatomy, IDIBELL-Bellvitge University Hospital, University of Barcelona, Hospitalet de Llobregat, Spain.|Neuropathology, CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Madrid, Spain.
authors.forename: Paula
authors.initials: P
authors.lastname: Garcia-Esparcia
authors.affiliation: Department of Genetics, Medical School, Alfonso X el Sabio University (UAX), Villanueva de la Cañada; Centro de Investigaciones Biologicas (CIB), CSIC, Madrid, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Gil
authors.affiliation: Neuropathology, CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Madrid, Spain.|Department of Molecular Biology, Center for Molecular Biology "Severo Ochoa" (CBMSO) CSIC/UAM, Madrid, 28049, Spain.
authors.forename: José J
authors.initials: JJ
authors.lastname: Lucas
authors.affiliation: Institute of Neuropathology, Service of Pathologic Anatomy, IDIBELL-Bellvitge University Hospital, University of Barcelona, Hospitalet de Llobregat, Spain.|Neuropathology, CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Madrid, Spain.
authors.forename: Isidre
authors.initials: I
authors.lastname: Ferrer
mesh_terms: D000328:Adult; D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology*; D016022:Case-Control Studies; D002452:Cell Count; D002467:Cell Nucleus / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism / Q000648:ultrastructure*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D035463:Pol1 Transcription Initiation Complex Proteins; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D035602:Transcriptional Elongation Factors / Q000378:metabolism; D016875:tau Proteins / Q000378:metabolism
chemical_list: D009687:Nuclear Proteins; D035463:Pol1 Transcription Initiation Complex Proteins; D012269:Ribosomal Proteins; D035602:Transcriptional Elongation Factors; D016875:tau Proteins; C063844:transcription factor UBF
keywords: Alzheimer's disease; elongation factors of protein synthesis; histones; initiation factors; nuclear tau; nucleolin; nucleolus; nucleophosmin; nucleoplasmin; nucleus; protein synthesis; ribosomal proteins; ribosome; upstream binding transcription factor RNA polymerase I