Fig. 2.

Disruption of the occludin gene. (A) Insertion of the gene trap and gene-targeting vectors in the mouse occludin locus. SA, splice acceptor; bpA, bovine growth hormone gene polyadenylation signal; E, EcoRV; N, NheI; P, PstI; S, SacI; X, XbaI. P1 and P2 represent the primers used for PCR. (B) Expression of occludin in GS cells by RT-PCR. (C) Southern blot analysis of a GS cell clone (clone 101). Genomic DNA was digested with the indicated restriction enzymes and hybridized with three different probes.