Fig. 2. The Tube localization gradient is enhanced in pelle mutant embryos. All images are surface views of embryos stained with antibodies to Tube detected with a Cy3-conjugated secondary antibody. (A) pll²⁵, lateral view of the posterior pole. (B) pll⁰⁷⁸; (C) pll¹⁶; (D) pll⁰⁷⁴, composite images, lateral aspect. In each image, an arrow indicates the approximate position of the ventral midline.