Hcy leads to phosphorylation, nuclear localization, and binding of β-catenin to the claudin-5 promoter. (A-B) Data were obtained by performing whole-cell ELISAs using the respective site-specific antiphosphotyrosine antibodies. (A) Initial screening of modification sites on β-catenin after 1-hour treatment with Hcy (100μM). (B) Time course for phosphorylation of β-catenin at Y86, a modification that has been associated with nuclear accumulation, in response to Hcy (20μM). (C) Chromatin immunoprecipitation assay performed by immunoprecipitation of β-catenin and PCR for the repression segment of the claudin-5 promoter region. Assay was run after 3 days of treatment with: Hcy (20μM), Ctrl (vehicle, PBS), Pos (positive control, whole cell lysate DNA), or Neg (negative control, primers only, no DNA).