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Challenges and Reinterpretation of Antibody-Based Research on Phosphorylation of Tyr³⁰⁷ on PP2Ac.

ABSTRACT: Aberrant hyperphosphorylation of the protein phosphatase 2A catalytic subunit (PP2Ac) at Tyr³⁰⁷ has been associated with aggressive disease and poor clinical outcome in multiple cancers. However, the study of reversible phosphorylation at this site has relied entirely upon the use of antibodies-most prominently, the clone E155. Here, we provide evidence that the E155 and F-8 phospho-Tyr³⁰⁷ antibodies cannot differentiate between phosphorylated and unphosphorylated forms of PP2Ac. The form of PP2Ac bound by these antibodies in H358 cells is unphosphorylated at the C-terminal tail. Furthermore, these antibodies are sensitive to additional protein modifications that occur near Tyr³⁰⁷, including Thr³⁰⁴ phosphorylation and Leu³⁰⁹ methylation, when these post-translational modifications are present. Thus, studies that used these antibodies to report PP2Ac hyperphosphorylation require reinterpretation, as these antibodies cannot be reliably used as readouts for a single PP2Ac post-translational modification (PTM) change.

SUBMITTER: Mazhar S

PROVIDER: S-EPMC7156886 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Challenges and Reinterpretation of Antibody-Based Research on Phosphorylation of Tyr307 on PP2Ac.

Mazhar Sahar S Leonard Daniel D Sosa Alejandro A Schlatzer Daniela D Thomas Dafydd D Narla Goutham G

Cell reports 20200301 9

Aberrant hyperphosphorylation of the protein phosphatase 2A catalytic subunit (PP2Ac) at Tyr307 has been associated with aggressive disease and poor clinical outcome in multiple cancers. However, the study of reversible phosphorylation at this site has relied entirely upon the use of antibodies-most prominently, the clone E155. Here, we provide evidence that the E155 and F-8 phospho-Tyr307 antibodies cannot differentiate between phosphorylated and unphosphorylated forms of ...[more]

PMID: 32130915

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Dataset Information

Challenges and Reinterpretation of Antibody-Based Research on Phosphorylation of Tyr³⁰⁷ on PP2Ac.

Publications

Challenges and Reinterpretation of Antibody-Based Research on Phosphorylation of Tyr<sup>307</sup> on PP2Ac.

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