Résumé
This chapter describes a simple experimental procedure to directly express fluorescent protein-tagged constitutive active receptor (CAR) in mouse liver in vivo. The procedure includes construction of a fluorescent protein-tagged CAR expression plasmid, delivering the plasmid to the liver through tail vein injection, preparation of liver frozen sections, and detection of the expressed receptor under conventional and/or confocal fluorescent microscopes. Using the tail vein injection method, fluorescent protein-tagged CAR can be effectively expressed in mouse liver cells. The expressed receptor is properly retained in the cytoplasm of the control livers, and PB treatment translocates the receptor into the liver nucleus. The method is experimentally simple and is a practical tool to investigate intracellular localization of a given protein and its molecular/cellular mechanisms. Despite difficulties, primary hepatocytes have advantages in the experimental system. Development of primary hepatocytes suitable for the experiments is an urgent issue to examine further details of the regulatory mechanism of PB-elicited nuclear translocation of CAR.