title: Antisense proline-arginine RAN dipeptides linked to C9ORF72-ALS/FTD form toxic nuclear aggregates that initiate in vitro and in vivo neuronal death.
abstract: Expanded GGGGCC (G4C2) nucleotide repeats within the C9ORF72 gene are the most common genetic mutation associated with both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Sense and antisense transcripts of these expansions are translated to form five dipeptide repeat proteins (DRPs). We employed primary cortical and motor neuron cultures, live-cell imaging, and transgenic fly models and found that the arginine-rich dipeptides, in particular Proline-Arginine (PR), are potently neurotoxic. Factors that anticipated their neurotoxicity included aggregation in nucleoli, decreased number of processing bodies, and stress granule formation, implying global translational dysregulation as path accountable for toxicity. Nuclear PR aggregates were also found in human induced motor neurons and postmortem spinal cord tissues from C9ORF72 ALS and ALS/FTD patients. Intronic G4C2 transcripts, but not loss of C9ORF72 protein, are also toxic to motor and cortical neurons. Interestingly, G4C2 transcript-mediated neurotoxicity synergizes with that of PR aggregates, suggesting convergence of mechanisms.
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Xinmei
authors.initials: X
authors.lastname: Wen
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Wenzhi
authors.initials: W
authors.lastname: Tan
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Westergard
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Karthik
authors.initials: K
authors.lastname: Krishnamurthy
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Shashirekha S
authors.initials: SS
authors.lastname: Markandaiah
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Yingxiao
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Shaoyu
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Neurology, The Center for Motor Neuron Biology and Disease, Columbia University Medical Center, New York, NY 10032, USA.
authors.forename: Neil A
authors.initials: NA
authors.lastname: Shneider
authors.affiliation: Department of Pediatrics, Child Neurology and Neurobiology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, One Children's Hospital Drive, 4401 Penn Avenue, Pittsburgh, PA 15224, USA.
authors.forename: John
authors.initials: J
authors.lastname: Monaghan
authors.affiliation: Department of Pediatrics, Child Neurology and Neurobiology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, One Children's Hospital Drive, 4401 Penn Avenue, Pittsburgh, PA 15224, USA.
authors.forename: Udai B
authors.initials: UB
authors.lastname: Pandey
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA.
authors.forename: Piera
authors.initials: P
authors.lastname: Pasinelli
authors.affiliation: Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Justin K
authors.initials: JK
authors.lastname: Ichida
authors.affiliation: Frances and Joseph Weinberg Unit for ALS Research, Department of Neuroscience, Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA. Electronic address: davide.trotti@jefferson.edu.
authors.forename: Davide
authors.initials: D
authors.lastname: Trotti
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000473:pathology*; D000818:Animals; D030801:Animals, Genetically Modified; D016375:Antisense Elements (Genetics) / Q000235:genetics / Q000633:toxicity*; D001120:Arginine; D000073885:C9orf72 Protein; D016923:Cell Death / Q000187:drug effects* / Q000235:genetics; D042622:DNA Repeat Expansion / Q000235:genetics; D004151:Dipeptides / Q000633:toxicity*; D004331:Drosophila melanogaster; D057180:Frontotemporal Dementia / Q000235:genetics / Q000473:pathology*; D006801:Humans; D009046:Motor Neurons / Q000187:drug effects / Q000473:pathology; D009474:Neurons / Q000187:drug effects* / Q000473:pathology*; D061251:Primary Cell Culture; D011392:Proline; D066263:Protein Aggregation, Pathological; D011506:Proteins / Q000235:genetics; D013116:Spinal Cord / Q000378:metabolism
chemical_list: D016375:Antisense Elements (Genetics); D000073885:C9orf72 Protein; C568651:C9orf72 protein, human; D004151:Dipeptides; D011506:Proteins; D001120:Arginine; D011392:Proline