Journal: Journal of Cellular and Molecular Medicine
Article Title: Phosphorylated PP2A (tyrosine 307) is associated with Alzheimer neurofibrillary pathology
doi: 10.1111/j.1582-4934.2008.00249.x
Figure Lengend Snippet: Characterization of the antibody to protein phosphatase 2A (PP2A) catalytic subunit phosphorylated (p) phosphorylated at Y307. Samples from control (Con) and Alzheimer's disease (AD) brain homogenates (15 μg /lane), AD p-tau (2 μg /lane), paired helical filaments (PHF)-tau (2 μg/lane), and extracts from non-treated (-) and serum-treated (+) NIH-3T3 cell lysates (control cell extracts, Cell signalling) were separated by 10% SDS-PAGE, and the membranes were developed with antibody to PP2Ac-Yp307 ( A ). Positive staining appeared at 36 kD that corresponds to the molecular mass of the catalytic subunit of PP2A molecular mass in homogenates and NIH-3T3 cell lysates, but not in AD p-tau or PHF-tau. In ( B ), human brain tissue homogenates were incubated with purified PTP1B to remove the phosphate on tyrosine sites. After the reaction the homogenates were separated by 10% SDS-PAGE, and the membranes were developed with antibody to PP2Ac-Yp307. No signal was detected by anti-pPP2A (Y307) after PTP1B treatment. In ( C ), representative pictures from sections of AD brains were immunostained with the antibody to PP2Ac-Yp307 in the presence of the corresponding blocking peptide or not. The sections absorbed with the blocking peptide (+) hardly showed any positive neuronal staining, as compared to sections without blocking peptide absorption (-). Data from Western blots and immunohistochemistry indicated that the antibody to PP2Ac-Yp307 is specific.
Article Snippet: pPP2A (Y307, poly) , PY307 (inactive form) , 1/100 , Santa Cruz.
Techniques: Control, SDS Page, Staining, Incubation, Purification, Blocking Assay, Western Blot, Immunohistochemistry