Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10636 (tau protein)
 5,110 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Accumulating evidence suggests that misfolded MAPT (microtubule associated protein tau), the main component of neurofibrillary tangles in tauopathies, is subject to degradation by the autophagy-lysosomal pathway. Selective autophagy is a subtype of macroautophagy that requires cargo receptors, such as OPTN (optineurin) or SQSTM1, to recognize specific targets for their sequestration within the autophagosome and their eventual degradation by the lysosome, although their roles in targeting distinct MAPT species have not been fully investigated. Using cargo receptor knockout cell lines and a seeding-based cellular assay in which neurofibrillary tangle pathology can be modeled in vitro, we reveal that while OPTN primarily targets soluble MAPT expressed in physiological conditions, SQSTM1 predominantly degrades insoluble but not soluble mutant MAPT. Endogenous SQSTM1 colocalizes with misfolded and aggregated MAPT species in vitro and in vivo, and both this colocalization and its function in MAPT clearance require both the LC3-interacting region (LIR) motif and also the PB1 self-polymerization domain of SQSTM1. Further, pathogenic MAPT accumulation reduces basal macroautophagy/autophagy in vitro and is associated with a compensatory upregulation of the lysosomal pathway in vivo. Finally, increased expression of SQSTM1 in MAPT transgenic mouse brains ameliorates MAPT pathology and prion-like spreading. Our results uncover distinct properties of selective autophagy receptors in targeting different MAPT species, implicate compromised autophagy as a potential underlying factor in mutant MAPT deposition, and demonstrate a potent and specific role of SQSTM1 in targeted clearance of pathogenic MAPT, through which it blocks neurofibrillary tangle accumulation and pathological spreading. Abbreviations: AAV: adeno-associated virus; AD: Alzheimer disease; ALP: autophagy-lysosomal pathway; ALS: amyotrophic lateral sclerosis; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; FTD: frontotemporal dementias; HD: Huntington disease; HTT: huntingtin; LIR: LC3-interacting region; NBR1: autophagy cargo receptor; NFE2L2/Nrf2: nuclear factor, erythroid derived 2, like 2; NFTs: neurofibrillary tangles; MAPT: microtubule associated protein tau; OPTN: optineurin; p-MAPT: hyperphosphorylated MAPT; PFA: paraformaldehyde; TARDBP/TDP-43: TAR DNA binding protein; TAX1BP1 Tax1: binding protein 1; ThioS: thioflavin-S; UBA: ubiquitin-associated.
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PMID:The cargo receptor SQSTM1 ameliorates neurofibrillary tangle pathology and spreading through selective targeting of pathological MAPT (microtubule associated protein tau). 3029 Jul 7

Mutations in the TANK-binding kinase 1 (TBK1) gene have recently been shown to cause frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The phenotype is highly variable and has been associated with behavioral variant FTD, primary progressive aphasia, and pure ALS. We describe the clinical, anatomical, and pathological features of a patient who developed corticobasal syndrome (CBS)/progressive nonfluent aphasia (PNFA) overlap. The patient presented with progressive speech difficulties and later developed an asymmetric akinetic-rigid syndrome. Neuroimaging showed asymmetrical frontal atrophy, predominantly affecting the right side. There was a strong family history of neurodegenerative disease with four out of seven siblings developing either dementia or ALS in their 50s and 60s. The patient died at the age of 71 and the brain was donated for postmortem analysis. Histopathological examination showed frontotemporal lobar degeneration TDP-43 type A pathology. Genetic screening did not reveal a mutation in the GRN, MAPT, or C9orf72 genes, but exome sequencing revealed a novel p.E703X mutation in the TBK1 gene. Although segregation data were not available, this loss-of-function mutation is highly likely to be pathogenic because it is predicted to disrupt TBK1/optineurin interaction and impair cellular autophagy. In conclusion, we show that TBK1 mutations can be a cause of an atypical parkinsonian syndrome and screening should be considered in CBS patients with a family history of dementia or ALS.
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PMID:A novel TBK1 mutation in a family with diverse frontotemporal dementia spectrum disorders. 3116 Mar 56