Effect of phosphorylation on interaction of human tau protein with 14-3-3zeta.
Interaction of the shortest isoform of tau protein (tau3) with human 14-3-3zeta was analyzed by means of native gel electrophoresis, chemical crosslinking and size-exclusion chromatography. Phosphorylation by cAMP-dependent protein kinase (up to 2 mole of phosphate per mole of tau3) strongly enhanced interaction of tau3 with 14-3-3. Apparent K(D) of the complexes formed by phosphorylated tau3 and 14-3-3 was close to 2 microM, whereas the corresponding constant for unphosphorylated tau3 was at least 10 times higher. The stoichiometry of the complexes formed by phosphorylated tau3 and 14-3-3 was variable and was different from 1:1. 14-3-3 decreased the probability of formation of chemically crosslinked large homooligomers of phosphorylated tau3 and at the same time induced formation of crosslinked heterooligomeric complexes of tau3 and 14-3-3 with an apparent molecular mass of 120-140 kDa.
Sluchanko
Nikolai N
NN
Department of Biochemistry, School of Biology, M.V. Lomonosov Moscow State University, Moscow 119991, Russian Federation.
Seit-Nebi
Alim S
AS
Gusev
Nikolai B
NB
D048948:14-3-3 Proteins / Q000737:chemistry / Q000378:metabolism*; D002850:Chromatography, Gel; D003432:Cross-Linking Reagents / Q000737:chemistry; D017868:Cyclic AMP-Dependent Protein Kinases / Q000737:chemistry / Q000378:metabolism; D004586:Electrophoresis; D006801:Humans; D010766:Phosphorylation; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D016875:tau Proteins / Q000737:chemistry / Q000378:metabolism*
D048948:14-3-3 Proteins; D003432:Cross-Linking Reagents; D020033:Protein Isoforms; D016875:tau Proteins; D017868:Cyclic AMP-Dependent Protein Kinases