title: Epitope mapping of monoclonal antibodies to the paired helical filaments of Alzheimer's disease: identification of phosphorylation sites in tau protein.
abstract: Tau is a neuronal phosphoprotein the expression of which is developmentally regulated. A single tau isoform is expressed in fetal human brain but six isoforms are expressed in adult human brain, with the fetal isoform corresponding to the shortest adult isoform. Phosphorylation is also developmentally regulated, as fetal tau is phosphorylated at more sites than adult tau. In Alzheimer's disease, the six adult tau isoforms become hyperphosphorylated and form the paired helical filament (PHF), the major fibrous component of the neurofibrillary lesions. One way to identify phosphorylated sites in tau is to use antibodies that recognize phosphorylated residues within a specific amino acid sequence. We here characterize the two novel phosphorylation-dependent anti-tau antibodies AT270 and AT180 and identify their epitopes as containing phosphorylated Thr-181 and Thr-231 respectively. With these antibodies we show that these two threonine residues are partially phosphorylated in fetal and adult tau and almost fully phosphorylated in PHF tau. This result contrasts with previous studies of Ser-202 and Ser-396 which are partially phosphorylated in fetal tau, unphosphorylated in adult tau but almost fully phosphorylated in PHF tau.
authors.affiliation: MRC Laboratory of Molecular Biology, Cambridge, UK.
authors.forename: M
authors.initials: M
authors.lastname: Goedert
authors.forename: R
authors.initials: R
authors.lastname: Jakes
authors.forename: R A
authors.initials: RA
authors.lastname: Crowther
authors.forename: P
authors.initials: P
authors.lastname: Cohen
authors.forename: E
authors.initials: E
authors.lastname: Vanmechelen
authors.forename: M
authors.initials: M
authors.lastname: Vandermeeren
authors.forename: P
authors.initials: P
authors.lastname: Cras
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D001665:Binding Sites; D001921:Brain / Q000254:growth & development; D001923:Brain Chemistry; D002540:Cerebral Cortex / Q000737:chemistry / Q000196:embryology / Q000254:growth & development; D000939:Epitopes / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D016874:Neurofibrillary Tangles / Q000737:chemistry*; D010766:Phosphorylation; D010769:Phosphothreonine / Q000032:analysis / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013329:Structure-Activity Relationship; D016875:tau Proteins / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D011994:Recombinant Proteins; D016875:tau Proteins; D010769:Phosphothreonine