Fig. 3.
Failure of β-catenin deletion in β-catenin(+) hepatic progenitor cells is attributed to low albumin promoter activity. (A) Genotyping analysis of DNA collected from livers of KO mice (lane 2, 3 mo old; lane 4, 17 mo old) and control WT mice (lane 1, 2 mo old), and of control hepatocytes purified by collagenase perfusion from the KO mouse (lane 2, 2 mo old). (B) Continuous liver tissue sections collected from 15-mo-old β-catenin–KO mice were processed for IHC staining with albumin and β-catenin antibodies. (C) Proteins extracted from the livers of WT and KO mice were processed for Western blotting probing with albumin and β-actin antibodies. (D) Serum albumin levels of WT and KO mice of various ages were determined. (E) The mRNA levels of Cre in livers from Alb-Cre (nondeleted β-catenin) and Alb-Cre;Ctnnb1flx/flx (β-catenin–KO) mice at the ages of 9 and 18 mo were examined by quantitative PCR (n = 3). The mean for 9-mo-old mice was standardized to a value of 1.0, and data were analyzed by using a t test (***P < 0.001). (Scale bar: 50 μM.)