Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-1-15
pubmed:abstractText
Pyramidal neurons in affected regions of Alzheimer's disease (AD) brain contain neurofibrillary tangles (NFT), aggregates of paired helical filaments (PHF) composed mainly of phosphorylated microtubule-associated protein tau. To explore the role of tau phosphorylation in the aggregation of tau into PHF, we constructed mammalian cell culture systems producing high levels of intracellular phosphorylated tau. COS-1 fibroblast-like cells were transiently transfected to simultaneously express tau, MAP kinase (MAPK), and MAP kinase kinase (MAPKK), or alternatively to express tau and glycogen synthase kinase 3 (GSK3). B103 neuron-like cells (which contain MAPK but little tau or GSK3) were stably transfected to express tau or tau and GSK3. In both systems, GSK3-transfected cells contained tau AT8/M (defined by AT8 staining and tau PHF-like mobility), but MAPK-transfected cells required phosphatase inhibitors, such as okadaic acid (OKA) or calyculin (CAL), to produce tau AT8/M. In vitro, the same concentrations of CAL and OKA inhibit phosphatases 1 and 2A (PP1 and PP2A), except that 100-1000 times as much OKA is needed to inhibit PP1. Inducing tau phosphorylation at the AT8 site in MAPK-transfected cells required 2-10 times more OKA than CAL, suggesting both PP1 and PP2A helped block the phosphorylation. Though levels of tau AT8/M reached 2-8% of total cellular proteins in COS-1 cells, the ratio of particulate to supernatant tau levels did not increase, and no tangles were observed; perhaps post-translational modifications or co-aggregating proteins are needed to induce PHF.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Calmodulin-Dependent..., http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Glycogen Synthase Kinase 3, http://linkedlifedata.com/resource/pubmed/chemical/Glycogen Synthase Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Microtubule-Associated Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase..., http://linkedlifedata.com/resource/pubmed/chemical/Okadaic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Oxazoles, http://linkedlifedata.com/resource/pubmed/chemical/Phosphoprotein Phosphatases, http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/calyculin A, http://linkedlifedata.com/resource/pubmed/chemical/tau Proteins
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0169-328X
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-17
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:8750856-Animals, pubmed-meshheading:8750856-Calcium-Calmodulin-Dependent Protein Kinases, pubmed-meshheading:8750856-Cell Line, pubmed-meshheading:8750856-Cercopithecus aethiops, pubmed-meshheading:8750856-Enzyme Inhibitors, pubmed-meshheading:8750856-Glycogen Synthase Kinase 3, pubmed-meshheading:8750856-Glycogen Synthase Kinases, pubmed-meshheading:8750856-Microtubule-Associated Proteins, pubmed-meshheading:8750856-Mitogen-Activated Protein Kinase Kinases, pubmed-meshheading:8750856-Neurofibrillary Tangles, pubmed-meshheading:8750856-Okadaic Acid, pubmed-meshheading:8750856-Oxazoles, pubmed-meshheading:8750856-Phosphoprotein Phosphatases, pubmed-meshheading:8750856-Phosphorylation, pubmed-meshheading:8750856-Protein Kinases, pubmed-meshheading:8750856-Rats, pubmed-meshheading:8750856-Transfection, pubmed-meshheading:8750856-tau Proteins
pubmed:year
1995
pubmed:articleTitle
Overexpressed tau protein in cultured cells is phosphorylated without formation of PHF: implication of phosphoprotein phosphatase involvement.
pubmed:affiliation
Department of Neurosciences, University of California, San Diego, La Jolla 92093-0624, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.