PP2A catalytic subunit pTyr307, Thermo Fisher Scientific, PA5-36874

Our team performed a comprehensive review of the scientific literature to identify studies using antibodies against human Protein Phosphatase 2A (PP2A), followed by extraction and evaluation of available data according to the pAbmAbs rating criteria. In this study, Frohner et al. conducted a head-to-head comparison of eight commercially available antibodies against PP2A catalytic subunit phosphorylated at Tyr307 (PP2Ac pTyr307). Antibody performance was evaluated by WB and ELISA, with particular emphasis on specificity for Tyr307 phosphorylation versus other post-translational modifications, including Leu309 methylation. For WB experiments, antibodies were tested using lysates from stably HA-PP2AC-expressing NIH 3T3 cells, transiently transfected HEK293T cells, HAP1 cells, and primary mouse CD4+ T cells under multiple experimental conditions, including phosphatase treatment, modulation of PP2A methylation, kinase activation, and site-directed mutagenesis. Peptide ELISA was performed using synthetic PP2A C-terminal peptides carrying defined combinations of post-translational modifications. Detailed experimental procedures are provided in the original publication (see reference). This antibody, PA5-36874 from Thermo Fisher Scientific, shows increased detection of PP2AC in WB following co-expression with SrcCA kinase. However, substantial signal is also observed with the non-phosphorylatable PP2AC Y307F mutant and after phosphatase treatment, demonstrating that the antibody does not specifically detect PP2AC pTyr307. The antibody was not evaluated by peptide ELISA in this study.