Transplantation of Xenopus laevis Lens Ectoderm

INTRODUCTIONIn Xenopus laevis, transplanting a piece of tissue from one site to another (other than into the blastocoel) is a useful way of examining the sequence of inductions required to produce a particular organ. For example, the young primordium of a particular organ can be transplanted from a young individual into an older embryo to determine whether the older embryo still has the capacity to induce the tissue to form the organ. Although this capacity can also be assayed using explants, the complex surroundings of the host embryo cannot be reproduced in an explant. This protocol describes how to transplant a piece of gastrula-stage animal cap ectoderm into the presumptive lens of a neural-plate-stage host embryo. Note that the technique can be adapted for use in other regions of the embryo. Care must be taken to inflict as little damage on the embryo as possible during this procedure. Well-treated embryos recover rapidly, whereas embryos with extensive injuries do not.