Project Summary Animal models are critical for biomedical research. They allow us to rapidly test the importance of any gene for development or diseases. Advances in technology now allow us to reduce or eliminate protein expression in the entire animal or in selected tissue. Similarly, mutations in the coding sequence of a gene associated with a disease can be introduce in animal model to test if they are indeed responsible for the disease state. Antibodies are critical tools to study protein localization and function. They can be used to block a protein function, send it for degradation, immunoprecipitate partners associated with the protein to identify functional complexes. While companies have focused on developing antibodies to human proteins, and to a lesser extend to mouse proteins, there is a need for antibodies that recognize proteins in diverse animal models. Despite the close similarity of protein sequences between human and mouse, many antibodies do not cross react. In addition, some proteins that have been recently identified or studied have not been targeted. Here we propose to produce antibodies against selected proteins in mouse, and amphibian (Xenopus and Axolotl) to facilitate the work in these animal models.