title: Increased expression of p62/SQSTM1 in prion diseases and its association with pathogenic prion protein.
abstract: Prion diseases are neurodegenerative disorders characterized by the aggregation of abnormally folded prion protein (PrP(Sc)). In this study, we focused on the mechanism of clearance of PrP(Sc), which remains unclear. p62 is a cytosolic protein known to mediate both the formation and degradation of aggregates of abnormal proteins. The levels of p62 protein increased in prion-infected brains and persistently infected cell cultures. Upon proteasome inhibition, p62 co-localized with PrP(Sc), forming a large aggregate in the perinuclear region, hereafter referred to as PrP(Sc)-aggresome. These aggregates were surrounded with autophagosome marker LC3 and lysosomes in prion-infected cells. Moreover, transient expression of the phosphomimic form of p62, which has enhanced ubiquitin-binding activity, reduced the amount of PrP(Sc) in prion-infected cells, indicating that the activation of p62 could accelerate the clearance of PrP(Sc). Our findings would thus suggest that p62 could be a target for the therapeutic control of prion diseases.
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Takujiro
authors.initials: T
authors.lastname: Homma
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ishibashi
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Nakagaki
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Satoh
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Sano
authors.affiliation: 1] Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan [2] Nagasaki University Research Centre for Genomic Instability and Carcinogenesis, Nagasaki 852-8523, Japan.
authors.forename: Ryuichiro
authors.initials: R
authors.lastname: Atarashi
authors.affiliation: Department of Molecular Microbiology and immunology, Graduate School of Biomedical sciences, Nagasaki University, Nagasaki 852-8523, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Nishida
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D015870:Gene Expression; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D008247:Lysosomes / Q000378:metabolism; D051379:Mice; D018620:PrPSc Proteins / Q000378:metabolism; D017096:Prion Diseases / Q000235:genetics / Q000378:metabolism*; D011328:Prions / Q000378:metabolism*; D066263:Protein Aggregation, Pathological; D011485:Protein Binding; D021381:Protein Transport; D059748:Proteolysis; D000071456:Sequestosome-1 Protein; D025801:Ubiquitin / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D006360:Heat-Shock Proteins; D018620:PrPSc Proteins; D011328:Prions; D000071456:Sequestosome-1 Protein; C101343:Sqstm1 protein, mouse; D025801:Ubiquitin