Construction of Transgenic Animals Overproducing Neurotrophins and Their Receptors

The development and analysis of transgenic mice that overexpress or misexpress neurotrophins or their receptors has led to a number of fundamental insights into the mechanisms whereby this family of growth factors exerts its biological effects in vivo (1 –5 ). These transgenic mice were generated when an appropriate foreign DNA construct, or transgene, expressing a neurotrophin or neurotrophin receptor was stably incorporated in the genome of every cell; the transgene, which was incorporated at the same chromosomal location(s) in germ-line and somatic cells, was transmitted to offspring in a Mendelian manner, allowing for a detailed analysis of the physiological consequences of perturbations in neurotrophin biology. Although conceptually simple, the generation and analysis of transgenic mice is a time-consuming and expensive process that is fraught with potential conceptual and technical problems. In this chapter, we provide (1) an overview of the steps involved in the production and analysis of transgenic mice that overexpress neurotrophins or their receptors, with an emphasis on targetting to neurons, and (2) detailed protocols for the characterization of transgenic mice at the level of DNA, RNA, and protein expression.