Adipose Tissue-Specific PPAR Gene Targeting

The nuclear receptor peroxisome proliferator activated receptor gamma (PPARγ) is most abundantly expressed in adipose tissue and has been shown to play imperative roles in controlling adipogenesis and lipogenesis in cultured cell systems in vitro as well as in mice and humans. However, it is unclear how important the role this receptor plays in regulating physiological functions of mature adipocytes in vivo. The Cre-loxP gene targeting strategy is employed to specifically disrupt PPARγ in mature adipocytes in mice. In this chapter, I will describe generation of “floxed” PPARγ mice, which bear loxP sequences in the introns of PPARγ gene locus flanking the coding exons 1 and 2 of PPARγ and creation of the aP2-Cre transgenic mice, which express Cre recombinase under the control of the promoter of adipocyte fatty acid binding protein (aP2). Crossing of the two mouse lines results in deletion of PPARγ gene only in differentiated adipocytes in Cre positive mice.