A method for the generation of conditional gene-targeted mice.

Integrins and cell adhesion molecules are required for cell adhesion and movement, as well as various biological functions such as development or immune responses. To elucidate their in vivo functions, mice lacking these molecules have been generated and various phenotypes analyzed. In the case of embryonic lethality or a requirement for spatiotemporal ablation of these genes, conditional gene-targeted mice have also been generated. Gene targeting is a powerful tool to study the function of proteins under physiological conditions and is a widely used method. Construction of targeting vectors and selection of homologous recombinant embryonic stem cells require delicate and elaborate technical procedures. In this chapter we describe the methods to generate conventional and conditional knockout mice.