Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-5-2
pubmed:abstractText
Carboxymethylation and phosphorylation of protein phosphatase 2A (PP2A) catalytic C subunit are evolutionary conserved mechanisms that critically control PP2A holoenzyme assembly and substrate specificity. Down-regulation of PP2A methylation and PP2A enzymes containing the B alpha regulatory subunit occur in Alzheimer's disease. In this study, we show that expressed wild-type and methylation- (L309 Delta) and phosphorylation- (T304D, T304A, Y307F, and Y307E) site mutants of PP2A C subunit differentially bind to B, B', and B''-type regulatory subunits in NIH 3T3 fibroblasts and neuro-2a (N2a) neuroblastoma cells. They also display distinct binding affinity for microtubules (MTs). Relative to controls, expression of the wild-type, T304A and Y307F C subunits in N2a cells promotes the accumulation of acetylated and detyrosinated MTs. However, expression of the Y307E, L309 Delta, and T304D mutants, which are impaired in their ability to associate with the B alpha subunit, induces their loss. Silencing of B alpha subunit in N2a and NIH 3T3 cells is sufficient to induce a similar breakdown of acetylated and detyrosinated MTs. It also confers increased sensitivity to nocodazole-induced MT depolymerization. Our findings suggest that changes in intracellular PP2A subunit composition can modulate MT dynamics. They support the hypothesis that reduced amounts of neuronal B alpha-containing PP2A heterotrimers contribute to MT destabilization in Alzheimer's disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
101
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
959-71
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Expression of protein phosphatase 2A mutants and silencing of the regulatory B alpha subunit induce a selective loss of acetylated and detyrosinated microtubules.
pubmed:affiliation
Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9073, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural