title: Novel neuronal cytoplasmic inclusions in a patient carrying SCA8 expansion mutation.
abstract: It has been reported that abnormal processing of pre-mRNA is caused by abnormal triplet expansion. Non-coding triplet expansions produce toxic RNA to alter RNA splicing activities. However, there has been no report on the globular RNA aggregation in neuronal cytoplasmic inclusions (NCIs) up to now. We herein report on an autopsy case (genetically determined as spinocerebellar atrophy 8 (SCA8)) with hitherto undescribed NCIs throughout the brain. NCIs were chiefly composed of small granular particles, virtually identical to ribosomes. Neurological features are comparable to the widespread lesions of the brain, including the spinal cord. Although 1C2-positivity of NCIs might be induced by reverse transcription of the CTG expansion, it remains to be clarified how abnormal aggregations of ribosome and extensive brain degeneration are related to the reverse or forward transcripts of the expanded repeat.
authors.affiliation: Department of Neurology, National Sagamihara Hospital, Kanagawa, Japan; Laboratory of Structural Neuropathology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Teruo
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Miyako
authors.initials: M
authors.lastname: Ishiyama
authors.forename: Kazuko
authors.initials: K
authors.lastname: Hasegawa
authors.forename: Toshiki
authors.initials: T
authors.lastname: Uchihara
authors.forename: Saburo
authors.initials: S
authors.lastname: Yagishita
mesh_terms: D000328:Adult; D003593:Cytoplasm / Q000648:ultrastructure; D042622:DNA Repeat Expansion; D006801:Humans; D002479:Inclusion Bodies / Q000235:genetics / Q000648:ultrastructure*; D008297:Male; D009474:Neurons / Q000648:ultrastructure*; D020754:Spinocerebellar Ataxias / Q000235:genetics / Q000473:pathology*
keywords: SCA8; TDP43; neuronal cytoplasmic inclusion; ribosomal aggregation; ultrastructure