Spectroscopic studies of GSK3{beta} phosphorylation of the neuronal tau protein and its interaction with the N-terminal domain of apolipoprotein E.
Alzheimer disease neurons are characterized by extraneuronal plaques formed by aggregated amyloid-β peptide and by intraneuronal tangles composed of fibrillar aggregates of the microtubule-associated Tau protein. Tau is mostly found in a hyperphosphorylated form in these tangles. Glycogen synthase kinase 3β (GSK3β) is a proline-directed kinase generally considered as one of the major players that (hyper)phosphorylates Tau. The kinase phosphorylates mainly (Ser/Thr)-Pro motifs and is believed to require a priming activity by another kinase. Here, we use an in vitro phosphorylation assay and NMR spectroscopy to characterize in a qualitative and quantitative manner the phosphorylation of Tau by GSK3β. We find that three residues can be phosphorylated (Ser-396, Ser-400, and Ser-404) by GSK3β alone, without priming. Ser-404 is essential in this process, as its mutation to Ala prevents all activity of GSK3β. However, priming enhances the catalytic efficacy of the kinase, as initial phosphorylation of Ser-214 by the cAMP-dependent protein kinase (PKA) leads to the rapid modification by GSK3β of four regularly spaced additional sites. Because the regular incorporation of negative charges by GSK3β leads to a potential parallel between phospho-Tau and heparin, we investigated its interaction with the heparin/low density lipoprotein receptor binding domain of human apolipoprotein E. We indeed observed an interaction between the GSK3β-promoted regular phospho-pattern on Tau and the apolipoprotein E fragment but none in the absence of phosphorylation or the presence of an irregular phosphorylation pattern by the prolonged activity of PKA. Apolipoprotein E is therefore able to discriminate and interact with specific phosphorylation patterns of Tau.
Leroy
Arnaud
A
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq; Laboratoire de Biochimie Appliquée, Faculté de Pharmacie à Châtenay-Malabry, University of Paris XI, 5 Rue Jean-Baptiste Clément, 92296 Châtenay-Malabry Cedex, France. Electronic address: Arnaud.Leroy@univ-lille1.fr.
Landrieu
Isabelle
I
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq.
Huvent
Isabelle
I
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq.
Legrand
Dominique
D
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq.
Codeville
Bernadette
B
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq.
Wieruszeski
Jean-Michel
JM
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq.
Lippens
Guy
G
From the Structural and Functional Glycobiology Unit, UMR8576 CNRS-University of Sciences and Technologies of Lille, 59655 Villeneuve d'Ascq. Electronic address: guy.lippens@univ-lille1.fr.
D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism; D019943:Amino Acid Substitution; D001057:Apolipoproteins E / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D038362:Glycogen Synthase Kinase 3 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D006801:Humans; D020125:Mutation, Missense; D019906:Nuclear Magnetic Resonance, Biomolecular; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D016875:tau Proteins / Q000235:genetics / Q000378:metabolism*
D001057:Apolipoproteins E; C054369:MAPT protein, human; D016875:tau Proteins; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta; D038362:Glycogen Synthase Kinase 3