Figure 4.
Claudin mRNA and protein levels are altered in Cdh1loxP/loxP Villin-Cre cKO small intestine compared with control tissue. (A) Levels of Claudin transcripts present in the intestinal epithelium of E18.5 control (n=3) and E-cadherin cKOs (n=3) were determined using qRT-PCR. Cldn1 was decreased, whereas Cldn3 and Cldn4 were increased. Gapdh was used for normalization. Error bars show SEM. A two-sample Student t test was used to determine p-value: *p≤0.05, **p≤0.01, ***p≤0.001 (B) Immunoblot analysis of E18.5 whole cell extracts demonstrated a decreased amount of CLDN1 protein in the intestine of Cdh1loxP/loxP Villin-Cre cKO animals compared with controls. In contrast, CLDN4 protein abundance was increased in E-cadherin cKO intestine compared with controls. Although gene array and qRT-PCR data showed Cldn3 to be higher in cKOs compared with controls, immunoblotting did not show a consistent increase in CLDN3 protein in E-cadherin cKO small intestine at E18.5. GAPDH was used as the loading control for these experiments.