6tjx | pdb_00006tjx

Cryo-EM structure of TypeII tau filaments extracted from the brains of individuals with Corticobasal degeneration

Loading... Status: waiting for Mol* initialization Structural highlights 6tjx is a 6 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: Electron Microscopy, Resolution 3Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease TAU_HUMAN Note=In Alzheimer disease, the neuronal cytoskeleton in the brain is progressively disrupted and replaced by tangles of paired helical filaments (PHF) and straight filaments, mainly composed of hyperphosphorylated forms of TAU (PHF-TAU or AD P-TAU). O-GlcNAcylation is greatly reduced in Alzheimer disease brain cerebral cortex leading to an increase in TAU/MAPT phosphorylations. Defects in MAPT are a cause of frontotemporal dementia (FTD) [MIM:600274; also called frontotemporal dementia (FTD), pallido-ponto-nigral degeneration (PPND) or historically termed Pick complex. This form of frontotemporal dementia is characterized by presenile dementia with behavioral changes, deterioration of cognitive capacities and loss of memory. In some cases, parkinsonian symptoms are prominent. Neuropathological changes include frontotemporal atrophy often associated with atrophy of the basal ganglia, substantia nigra, amygdala. In most cases, protein tau deposits are found in glial cells and/or neurons. Defects in MAPT are a cause of Pick disease of the brain (PIDB) [MIM:172700. It is a rare form of dementia pathologically defined by severe atrophy, neuronal loss and gliosis. It is characterized by the occurrence of tau-positive inclusions, swollen neurons (Pick cells) and argentophilic neuronal inclusions known as Pick bodies that disproportionally affect the frontal and temporal cortical regions. Clinical features include aphasia, apraxia, confusion, anomia, memory loss and personality deterioration. Note=Defects in MAPT are a cause of corticobasal degeneration (CBD). It is marked by extrapyramidal signs and apraxia and can be associated with memory loss. Neuropathologic features may overlap Alzheimer disease, progressive supranuclear palsy, and Parkinson disease. Defects in MAPT are a cause of progressive supranuclear palsy type 1 (PSNP1) [MIM:601104; also abbreviated as PSP and also known as Steele-Richardson-Olszewski syndrome. PSNP1 is characterized by akinetic-rigid syndrome, supranuclear gaze palsy, pyramidal tract dysfunction, pseudobulbar signs and cognitive capacities deterioration. Neurofibrillary tangles and gliosis but no amyloid plaques are found in diseased brains. Most cases appear to be sporadic, with a significant association with a common haplotype including the MAPT gene and the flanking regions. Familial cases show an autosomal dominant pattern of transmission with incomplete penetrance; genetic analysis of a few cases showed the occurrence of tau mutations, including a deletion of Asn-613. Defects in MAPT are a cause of Parkinson-dementia syndrome (PARDE) [MIM:260540. A syndrome characterized by parkinsonism tremor, rigidity, dementia, ophthalmoparesis and pyramidal signs. Neurofibrillary degeneration occurs in the hippocampus, basal ganglia and brainstem nuclei. Function TAU_HUMAN Promotes microtubule assembly and stability, and might be involved in the establishment and maintenance of neuronal polarity. The C-terminus binds axonal microtubules while the N-terminus binds neural plasma membrane components, suggesting that tau functions as a linker protein between both. Axonal polarity is predetermined by TAU/MAPT localization (in the neuronal cell) in the domain of the cell body defined by the centrosome. The short isoforms allow plasticity of the cytoskeleton whereas the longer isoforms may preferentially play a role in its stabilization. Publication Abstract from PubMed Corticobasal degeneration (CBD) is a neurodegenerative tauopathy that is characterised by motor and cognitive disturbances(1-3). A higher frequency of the H1 haplotype of MAPT, the tau gene, is present in cases of CBD than in controls(4,5) and genome-wide association studies have identified additional risk factors(6). By histology, astrocytic plaques are diagnostic of CBD(7,8), as are detergent-insoluble tau fragments of 37 kDa by SDS-PAGE(9). Like progressive supranuclear palsy (PSP), globular glial tauopathy (GGT) and argyrophilic grain disease (AGD)(10), CBD is characterized by abundant filamentous tau inclusions that are made of isoforms with four microtubule-binding repeats (4R)(11-15). This distinguishes 4R tauopathies from Pick's disease, filaments of which are made of three-repeat (3R) tau isoforms, and from Alzheimer's disease and chronic traumatic encephalopathy (CTE), where both 3R and 4R tau isoforms are found in the filaments(16). Here we report the structures of tau filaments extracted from the brains of three individuals with CBD using electron cryo-microscopy (cryo-EM). They were identical between cases, but distinct from those of Alzheimer's disease, Pick's disease and CTE(17-19). The core of CBD filaments comprises residues K274-E380 of tau, spanning the last residue of R1, the whole of R2, R3 and R4, as well as 12 amino acids after R4. It adopts a novel four-layered fold, which encloses a large non-proteinaceous density. The latter is surrounded by the side chains of lysine residues 290 and 294 from R2 and 370 from the sequence after R4. CBD is the first 4R tauopathy with filaments of known structure. Novel tau filament fold in corticobasal degeneration.,Zhang W, Tarutani A, Newell KL, Murzin AG, Matsubara T, Falcon B, Vidal R, Garringer HJ, Shi Y, Ikeuchi T, Murayama S, Ghetti B, Hasegawa M, Goedert M, Scheres SHW Nature. 2020 Feb 12. pii: 10.1038/s41586-020-2043-0. doi:, 10.1038/s41586-020-2043-0. PMID:32050258 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Microtubule-associated protein 3D structures Tau protein 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA