title: Expression of a paired helical filament tau epitope in embryonic chicken central nervous system.
abstract: Immunoblots from embryonic chicken optic lobes (midbrain) and spinal cord were found to contain different proteins with a molecular weight between 45 and 70 kDa that are recognized by monoclonal antibodies (mAbs) directed at human tau proteins. Each appears as a doublet on SDS-PAGE. The upper, slower migrating bands were recognized by AT8, a monoclonal antibody that requires a phosphorylated Ser-202, an epitope specific for abnormally phosphorylated tau of paired helical filaments (PHF-tau) in Alzheimer brains. The corresponding faster migrating bands were stained by the mAbs BT2 and tau-1, both requiring an epitope containing a non-phosphorylated Ser-202. Phosphatase treatment abolished binding of AT8 and induced an additional binding of tau-1 (and BT2) to the upper bands. Thus, the data suggest that in embryonic chicken central nervous system Ser-202 occurs in a phosphorylated and in a non-phosphorylated state in several distinct tau isoforms.
authors.affiliation: Institute of Zoology, University of Hohenheim, Stuttgart, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Rösner
authors.forename: M
authors.initials: M
authors.lastname: Rebhan
authors.forename: G
authors.initials: G
authors.lastname: Vacun
authors.forename: E
authors.initials: E
authors.lastname: Vanmechelen
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D001921:Brain / Q000254:growth & development / Q000276:immunology / Q000378:metabolism; D002490:Central Nervous System / Q000378:metabolism*; D002642:Chick Embryo; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000276:immunology*; D015151:Immunoblotting; D010744:Phosphoric Monoester Hydrolases / Q000494:pharmacology; D013116:Spinal Cord / Q000254:growth & development / Q000276:immunology / Q000378:metabolism; D016875:tau Proteins / Q000096:biosynthesis* / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D016875:tau Proteins; D010744:Phosphoric Monoester Hydrolases