title: The effect of deleting residue C269 in the β12-β13 loop of protein phosphatase 2A (PP2A)catalytic subunit on the interaction between PP2A and metal ions, especially Mn(2+).
abstract: Protein phosphatase 2A (PP2A) is one of the most important Ser/Thr phosphatases in eukaryotic cells. The enzymatic core of PP2A (PP2A(D)) consists of a scaffold subunit (A subunit) and a catalytic subunit (C subunit). When residue Cys269 in the β12-β13 loop of the PP2A C subunit was deleted (ΔC269), the activity and the intrinsic fluorescence intensity of PP2A(D) decreased. Specify the effects of some metal ions on PP2A(D) were also changed. Mn(2+) in particular was an efficient activator of ΔC269 and altered the intrinsic fluorescence spectrum of ΔC269. Remarkably, after pre-treatment of ΔC269 with Mn(2+), the effects of other metal ions showed the same trends as they had on the WT. Molecular dynamics (MD) simulations showed that deletion of Cys269 decreased the polarity of the β12-β13 loop of PP2A Cα. We conclude that deletion of residue Cys269 alters the conformation and activity of PP2A(D) and influences the interaction between PP2A and various metal ions, notably Mn(2+).
authors: Department of Biochemistry and Molecular Biology, Beijing Normal University, Beijing, People's Republic of China.
authors: Hui
authors: H
authors: Li
authors: Chao
authors: C
authors: Liu
authors: Hao
authors: H
authors: Zhang
authors: Qun
authors: Q
authors: Wei
mesh_terms: D000818:Animals; D020134:Catalytic Domain / Q000235:genetics*; D002478:Cells, Cultured; D006801:Humans; D007313:Insecta; D007477:Ions / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D008345:Manganese / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D008670:Metals / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D016297:Mutagenesis, Site-Directed; D011485:Protein Binding; D017510:Protein Folding / Q000187:drug effects; D054730:Protein Interaction Domains and Motifs / Q000235:genetics; D054648:Protein Phosphatase 2 / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D017433:Protein Structure, Secondary / Q000187:drug effects / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D017384:Sequence Deletion / Q000502:physiology; D013050:Spectrometry, Fluorescence
chemical_list: D007477:Ions; D008670:Metals; D011994:Recombinant Proteins; D008345:Manganese; D054648:Protein Phosphatase 2