Fig. 4. DH31-R expression in the principal cells of Malpighian tubules. Malpighian tubules from individual progeny of a c724::GAL4 cross to UAS::lacZ were double stained with antibodies for CG17415 and ß-galactosidase (center). Note the specific labeling of the stellate cells (left, arrow) with the anti-ß-gal antibody and the complementary labeling in the principal cells (right, arrow) of the tubules with anti-CG17415.