title: hnRNP A3 binds to GGGGCC repeats and is a constituent of p62-positive/TDP43-negative inclusions in the hippocampus of patients with C9orf72 mutations.
abstract: Genetic analysis revealed the hexanucleotide repeat expansion GGGGCC within the regulatory region of the gene C9orf72 as the most common cause of familial amyotrophic lateral sclerosis and the second most common cause of frontotemporal lobar degeneration. Since repeat expansions might cause RNA toxicity via sequestration of RNA-binding proteins, we searched for proteins capable of binding to GGGGCC repeats. In vitro-transcribed biotinylated RNA containing hexanucleotide GGGGCC or, as control, AAAACC repeats were incubated with nuclear protein extracts. Using stringent filtering protocols 20 RNA-binding proteins with a variety of different functions in RNA metabolism, translation and transport were identified. A subset of these proteins was further investigated by immunohistochemistry in human autopsy brains. This revealed that hnRNP A3 formed neuronal cytoplasmic and intranuclear inclusions in the hippocampus of patients with C9orf72 repeat extensions. Confocal microcopy showed that these inclusions belong to the group of the so far enigmatic p62-positive/TDP-43 negative inclusions characteristically seen in autopsy cases of diseased C9orf72 repeat expansion carriers. Thus, we have identified one protein component of these pathognomonic inclusions.
authors: Adolf-Butenandt-Institute, Biochemistry, Ludwig-Maximilians-University, Schillerstr. 44, 80336, Munich, Germany.
authors: Kohji
authors: K
authors: Mori
authors: Sven
authors: S
authors: Lammich
authors: Ian R A
authors: IR
authors: Mackenzie
authors: Ignasi
authors: I
authors: Forné
authors: Sonja
authors: S
authors: Zilow
authors: Hans
authors: H
authors: Kretzschmar
authors: Dieter
authors: D
authors: Edbauer
authors: Jonathan
authors: J
authors: Janssens
authors: Gernot
authors: G
authors: Kleinberger
authors: Marc
authors: M
authors: Cruts
authors: Jochen
authors: J
authors: Herms
authors: Manuela
authors: M
authors: Neumann
authors: Christine
authors: C
authors: Van Broeckhoven
authors: Thomas
authors: T
authors: Arzberger
authors: Christian
authors: C
authors: Haass
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000073885:C9orf72 Protein; D002851:Chromatography, High Pressure Liquid; D004268:DNA-Binding Proteins / Q000378:metabolism; D057174:Frontotemporal Lobar Degeneration / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005786:Gene Expression Regulation / Q000235:genetics; D057809:HEK293 Cells; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B / Q000378:metabolism*; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D002479:Inclusion Bodies / Q000378:metabolism* / Q000473:pathology; D013058:Mass Spectrometry; D009154:Mutation / Q000235:genetics*; D011506:Proteins / Q000235:genetics*; D034741:RNA, Small Interfering / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid / Q000502:physiology*; D000071456:Sequestosome-1 Protein; D014162:Transfection
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000073885:C9orf72 Protein; C568651:C9orf72 protein, human; D004268:DNA-Binding Proteins; C502034:HNRNPA3 protein, human; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D011506:Proteins; D034741:RNA, Small Interfering; C099718:SQSTM1 protein, human; D000071456:Sequestosome-1 Protein