Xenopus laevis organizer
These twinned Xenopus laevis embryos were generated by grafting the dorsal inductive tissue of the Spemann Organizer into the ventral region of a gastrula-stage host embryo. An antibody stain for the epitope Tor70 (dark brown) reveals both the native and secondary notochords.
Image(s) by Andrea Wills (2007 Woods Hole Embryology Course)
Harland lab, UC Berkeley