Fig 1.

Liver-specific deletion of Arfrp1 after Cre-mediated recombination. (A) Deletion of exons 2 to 4 of the Arfrp1 gene was detected by RT-PCR performed on cDNA generated from isolated RNA. RT-PCR with primers located on exons 1 and 5 amplified a 450-bp fragment in control Arfrp1^flox/flox (f/f) animals and in nonhepatic tissues of Arfrp1^liv−/− (KO) mice, whereas Cre recombinase-mediated deletion generated a truncated smaller 150-bp fragment in livers of Arfrp1^liv−/− mice. (B) Arfrp1 mRNA levels in different tissues detected by qRT-PCR in Arfrp1^liv−/− and control mice resulted in reduced mRNA exclusively in Arfrp1^liv−/− livers at the age of 5 weeks (37.8% ± 7.5%; U = 3, n = 20, and P < 0.001). (C) ARFRP1 protein in indicated tissues of Arfrp1^liv−/− and control mice detected by Western blotting. ARFRP1 protein was absent exclusively in livers of 5-week-old Arfrp1^liv−/− mice. Lysates from 3T3-L1 adipocytes were positive controls. WAT, white adipose tissue; BAT, brown adipose tissue; SM, skeletal muscle. GAPDH antibody was used as a loading control. ***, P < 0.001.