Colocalization of Wt1 and EPO proteins in the developing murine dorsal root ganglion. Double-immunofluorescence labeling of Wt1 (red) and EPO (green) in sections of the murine spinal cord and dorsal root ganglion. (A,C) Staining of Wt1. (B) Negative control. Wt1 is contained in the nuclei of neuronal cells in the dorsal root ganglion and in a subtype of neurons in the mantle layer of the spinal cord at E14.0 of gestation (A, arrows). Nuclear localization of Wt1 is confirmed by counterstaining with DAPI (H). (D,F) Staining of EPO. (E) Negative control. Note the colocalization of Wt1 and EPO in neuronal cells of the developing dorsal root ganglion (drg), which becomes evident by the intense yellow fluorescence upon merging the red and green signals (I). Cy2 fluorescence in the primordial cartilage of the neural cord represents unspecific staining (F). Counterstaining with DAPI is shown (G). ml indicates mantle layer; el, ependymal layer; mrl, marginal layer; lm, long muscles of the neck; cp, cartilage primordium of neural cord.