Browsing by Author "Kametani, Fuyuki"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Structure-based Classification of Tauopathies
    (Springer Nature, 2021) Shi, Yang; Zhang, Wenjuan; Yang, Yang; Murzin, Alexey G.; Falcon, Benjamin; Kotecha, Abhay; van Beers, Mike; Tarutani, Airi; Kametani, Fuyuki; Garringer, Holly J.; Vidal, Ruben; Hallinan, Grace I.; Lashley, Tammaryn; Saito, Yuko; Murayama, Shigeo; Yoshida, Mari; Tanaka, Hidetomo; Kakita, Akiyoshi; Ikeuchi, Takeshi; Robinson, Andrew C.; Mann, David M.A.; Kovacs, Gabor G.; Revesz, Tamas; Ghetti, Bernardino; Hasegawa, Masato; Goedert, Michel; Scheres, Sjors H.W.; Pathology and Laboratory Medicine, School of Medicine
    The ordered assembly of tau protein into filaments characterizes several neurodegenerative diseases, which are called tauopathies. It was previously reported that, by cryo-electron microscopy, the structures of tau filaments from Alzheimer's disease1,2, Pick's disease3, chronic traumatic encephalopathy4 and corticobasal degeneration5 are distinct. Here we show that the structures of tau filaments from progressive supranuclear palsy (PSP) define a new three-layered fold. Moreover, the structures of tau filaments from globular glial tauopathy are similar to those from PSP. The tau filament fold of argyrophilic grain disease (AGD) differs, instead resembling the four-layered fold of corticobasal degeneration. The AGD fold is also observed in ageing-related tau astrogliopathy. Tau protofilament structures from inherited cases of mutations at positions +3 or +16 in intron 10 of MAPT (the microtubule-associated protein tau gene) are also identical to those from AGD, suggesting that relative overproduction of four-repeat tau can give rise to the AGD fold. Finally, the structures of tau filaments from cases of familial British dementia and familial Danish dementia are the same as those from cases of Alzheimer's disease and primary age-related tauopathy. These findings suggest a hierarchical classification of tauopathies on the basis of their filament folds, which complements clinical diagnosis and neuropathology and also allows the identification of new entities-as we show for a case diagnosed as PSP, but with filament structures that are intermediate between those of globular glial tauopathy and PSP.
  • Thumbnail Image
    Item
    Structures of α-Synuclein Filaments from Multiple System Atrophy
    (Springer Nature, 2020-09) Schweighauser, Manuel; Shi, Yang; Tarutani, Airi; Kametani, Fuyuki; Murzin, Alexey G.; Ghetti, Bernardino; Matsubara, Tomoyasu; Tomita, Taisuke; Ando, Takashi; Hasegawa, Kazuko; Murayama, Shigeo; Yoshida, Mari; Hasegawa, Masato; Scheres, Sjors H.W.; Goedert, Michel; Pathology and Laboratory Medicine, School of Medicine
    Synucleinopathies, which include multiple system atrophy (MSA), Parkinson's disease, Parkinson's disease with dementia and dementia with Lewy bodies (DLB), are human neurodegenerative diseases1. Existing treatments are at best symptomatic. These diseases are characterized by the presence of, and believed to be caused by the formation of, filamentous inclusions of α-synuclein in brain cells2,3. However, the structures of α-synuclein filaments from the human brain are unknown. Here, using cryo-electron microscopy, we show that α-synuclein inclusions from the brains of individuals with MSA are made of two types of filament, each of which consists of two different protofilaments. In each type of filament, non-proteinaceous molecules are present at the interface of the two protofilaments. Using two-dimensional class averaging, we show that α-synuclein filaments from the brains of individuals with MSA differ from those of individuals with DLB, which suggests that distinct conformers or strains characterize specific synucleinopathies. As is the case with tau assemblies4-9, the structures of α-synuclein filaments extracted from the brains of individuals with MSA differ from those formed in vitro using recombinant proteins, which has implications for understanding the mechanisms of aggregate propagation and neurodegeneration in the human brain. These findings have diagnostic and potential therapeutic relevance, especially because of the unmet clinical need to be able to image filamentous α-synuclein inclusions in the human brain.
  • Thumbnail Image
    Item
    TDP-43 forms amyloid filaments with a distinct fold in type A FTLD-TDP
    (Springer Nature, 2023) Arseni, Diana; Chen, Renren; Murzin, Alexey G.; Peak-Chew, Sew Y.; Garringer, Holly J.; Newell, Kathy L.; Kametani, Fuyuki; Robinson, Andrew C.; Vidal, Ruben; Ghetti, Bernardino; Hasegawa, Masato; Ryskeldi-Falcon, Benjamin; Pathology and Laboratory Medicine, School of Medicine
    The abnormal assembly of TAR DNA-binding protein 43 (TDP-43) in neuronal and glial cells characterizes nearly all cases of amyotrophic lateral sclerosis (ALS) and around half of cases of frontotemporal lobar degeneration (FTLD)1,2. A causal role for TDP-43 assembly in neurodegeneration is evidenced by dominantly inherited missense mutations in TARDBP, the gene encoding TDP-43, that promote assembly and give rise to ALS and FTLD3-7. At least four types (A-D) of FTLD with TDP-43 pathology (FTLD-TDP) are defined by distinct brain distributions of assembled TDP-43 and are associated with different clinical presentations of frontotemporal dementia8. We previously showed, using cryo-electron microscopy, that TDP-43 assembles into amyloid filaments in ALS and type B FTLD-TDP9. However, the structures of assembled TDP-43 in FTLD without ALS remained unknown. Here we report the cryo-electron microscopy structures of assembled TDP-43 from the brains of three individuals with the most common type of FTLD-TDP, type A. TDP-43 formed amyloid filaments with a new fold that was the same across individuals, indicating that this fold may characterize type A FTLD-TDP. The fold resembles a chevron badge and is unlike the double-spiral-shaped fold of ALS and type B FTLD-TDP, establishing that distinct filament folds of TDP-43 characterize different neurodegenerative conditions. The structures, in combination with mass spectrometry, led to the identification of two new post-translational modifications of assembled TDP-43, citrullination and monomethylation of R293, and indicate that they may facilitate filament formation and observed structural variation in individual filaments. The structures of TDP-43 filaments from type A FTLD-TDP will guide mechanistic studies of TDP-43 assembly, as well as the development of diagnostic and therapeutic compounds for TDP-43 proteinopathies.