Fig. 10.

Detection of KCNN4b- and KCNN4c-specific proteins in apical and basolateral membranes of the rat distal colon. Western blot analyses were performed using anti-KCNN4-abc antibody as described in materials and methods. A: anti-KCNN4-abc polyclonal antibody detects 37, 40, 50, and 120 kDa proteins in proximal and distal colonic mucosal homogenate (left). Both 37- and 40-kDa proteins detected by the anti-KCNN4-abc antibody were eliminated when the antibody was preincubated with a 50-fold molar excess of competitor peptide corresponding to the epitope recognition sequence before blotting in both proximal and distal colon (right). B: anti-KCNN4-abc antibody detects 37- and 40-kDa proteins in colonic epithelial cell homogenate (Homo), whereas it detects 37- and 40kDa proteins in apical (APM) and basolateral (BLM) membranes, respectively.