CONSTRUCTION OF A TARGETING VECTOR BY RECOMBINEERING AND GENERATION OF CEBPD CONDITIONAL KNOCKOUT MICE FOR THE STUDY OF CELL-TYPE SPECIFIC FUNCTIONS OF C/EBPδ IN VIVO

Abstract

The Cebpd gene encodes the transcription factor C/EBPδ. A germ line deletion of the Cebpd gene in mice increased tumor multiplicity but reduced metastatic progression in a transgenic model of mammary tumorigenesis, indicating that C/EBPδ can be both a tumor suppressor and tumor promoter. To address whether these phenotypes were caused by C/EBPδ functions in mammary epithelial cells and/or cells of the tumor microenvironment, we needed a conditional knockout (cko) mouse model where the Cebpd gene can be deleted by cell-type specific expression of a Cre recombinase transgene. I have used homologous recombination technology to construct a cko targeting vector in which Cre recombination sites were placed on either side of the Cebpd coding region. This vector was used to generate mice carrying a Cebpd cko allele, and that can now be crossed into various mouse models to study cell-type specific deletions of Cebpd.