title: Discoveries of tau, abnormally hyperphosphorylated tau and others of neurofibrillary degeneration: a personal historical perspective.
abstract: Alzheimer disease was described by Alois Alzheimer in 1907, but it was not until approximately 60-70 years later that any new significant developments were reported on the pathology of this disease. The discoveries that laid down the foundation for the exciting research that has been carried out during the last approximately 20 years and that have significantly enhanced our understanding of the disease are the ultrastructure of neurofibrillary tangles and neuritic (senile) plaques, the clinical-pathological correlation of these lesions to the presence of dementia, and the bulk isolation and protein composition of paired helical filaments and plaque amyloid. We discovered tau as the major protein subunit of paired helical filaments/neurofibrillary tangles, the abnormal hyperphosphorylation of this protein in this lesion and in Alzheimer brain cytosol and the gain of toxic function by the cytosolic abnormally hyperphosphorylated tau in Alzheimer brain. Here we present a personal historical account of the work in our laboratories that led, in 1986, to the discoveries of tau and its abnormal hyperphosphorylation in paired helical filaments and Alzheimer brain cytosol. This article also describes several major findings which subsequently resulted from the abnormal hyperphosphorylation of tau and in a large part account for the current understanding of the role of this lesion in Alzheimer disease and other tauopathies.
authors.affiliation: New York State Institute for Basic Research, in Developmental Disabilities, Department of Neurochemistry, 1050 Forest Hill Road, Staten Island, New York 10314-6399, USA. iqbalk@worldnet.att.net
authors.forename: Khalid
authors.initials: K
authors.lastname: Iqbal
authors.forename: Inge
authors.initials: I
authors.lastname: Grundke-Iqbal
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism*; D015153:Blotting, Western; D051360:Cyclin-Dependent Kinase 5 / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D009410:Nerve Degeneration / Q000473:pathology*; D016874:Neurofibrillary Tangles / Q000378:metabolism* / Q000473:pathology*; D010766:Phosphorylation; D016875:tau Proteins / Q000378:metabolism*
chemical_list: D016564:Amyloid beta-Protein Precursor; D016875:tau Proteins; D051360:Cyclin-Dependent Kinase 5