Methods for Manipulating the Chick Limb Bud to Study Gene Expression, Tissue Interactions, and Patterning

From the beginnings of experimental embryology (1 ) through the present day, the developing chick limb has proven a fruitful system to study. The results of these studies have demonstrated the ability of the limb bud to self-differentiate (2 ), the role of cellular and tissue interactions during limb budding and differentiation (reviewed in [3 ]), and recently, the relationship of particular gene expressions to pattern formation and differentiation (reviewed in [4 ]). The ability to manipulate the developing chick limb bud, with survival even through hatching, has permitted the insight that three interdependent organizing centers control cascades of gene expressions that permit limb development (reviewed in [5 ]). Here we describe several common methods of manipulating the chick limb bud. These techniques, above all, require patience. It is our experience that most investigators can master these procedures; the more sensitive the investigator is to the needs of the embryo, the greater his/her success.