RESUMO
The quail-chick chimera is a stable and precise labeling technique that allows tracing of definite cells and their progeny without interfering with normal development of two related avian species. This technique utilizes the transplantation of quail tissues into chick embryo or vice versa. The region of interest (graft) is removed from the donor and replaced in the stage-matched host embryo. The quail-chick chimeras can be analyzed by immunolabeling donor-derived cells with species-specific antibodies, or by differential staining of the nucleus. The use of the quail-chick chimera technique is valuable to eye development studies since its formation involves coalition of tissues from different embryonic origins: the ectoderm, neuroectoderm, and neural crest cells derived from the interaction between the ectoderm and neural ectoderm. This chapter describes the protocols for using quail-chick chimeras to identify neural crest- and ectoderm-derived components of the eye. This technique can be used in combination with molecular biology techniques in functional studies to determine the cellular and tissue interactions involved in eye development.