Expression of Rhbg and Rhcg in different intercalated cell populations. The expression and localization of Rhbg and Rhcg differ in the type A, type B, and non-A, non-B intercalated cells. The type A intercalated cell, characterized by apical H+-ATPase and basolateral AE1, expresses apical and basolateral Rhcg and basolateral Rhbg. The type B intercalated cell, characterized by apical pendrin and basolateral H+-ATPase, does not express either Rhbg or Rhcg detectable by immunohistochemistry. The non-A, non-B intercalated cell, characterized by apical pendrin and apical H+-ATPase, expresses apical, but not basolateral, Rhcg and expresses basolateral Rhbg. This figure is based on a drawing originally prepared by Dr. Ki-Hwan Han.