Follicle of the giant silkmoth Hyalophora cecropia.
The "delta" region of a developing follicle of the giant silkmoth Hyalophora cecropia stained with an antibody against the largest subunit of the Drosophila RNA polymerase II (RNAp II). The primary antibody was visualized using a biotinylated secondary antibody followed by Texas Red® dye–conjugated streptavidin (Cat. No. S872). The distribution of the RNAp II appears violet because the Texas Red® staining colocalizes with the blue autofluorescence of the yolk granules. Image contributed by Ivo Sauman, Wesleyan University.