The establishment of microinjection protocols about 20 years ago for cultured cells and shortly thereafter for the generation of transgenic mice by microinjection of DNA into fertilized mouse eggs greatly influ- enced many fields of biology. Not only have the data generated using these approaches contributed to a large extent to our present under- standing of gene regulation and cellular function of higher eukaryotic cells, but current knowledge and future developments in this area will certainly have a great impact on basic and applied research for many years to come. This laboratory manual...