WNK4 was immunoprecipitated from 1 mg of mouse DCT cells (which prior to lysis had been treated with various stimulants) using 20 ug of anti-WNK4 (41 – 55) [S235B] antibody. The immunoprecipitates were subjected to SDS-Page, transferred to nitrocellulose and immunoblotted with anti-WNK4 (1221 – 1243) [S064B] at 2 ug/ml. Binding of the primary antibody was detected using rabbit peroxidase conjugated anti- sheep IgG antibody (1 in 10, 000 dilution, Pierce) followed by enhanced chemiluminescence (ECL, Amersham).