
Conditional knockout vector construction. (a–f) Sequential steps leading to a NOD2 exon 3 recombinant BAC and targeting vector (see text for details). (g) Gel electrophoresis depicting PCR products confirming the recombinants schematized in diagrams: (a) lane 1 (WT-BAC), (b) lane 2 (BACloxP/frt/aph/frt), and (c) lane 3 (BACloxP), generated with primers 1 (P1) and 2 (P2); (d) lane 4 (BACloxP) and (e) lane 5 (BACloxP-loxP/aph/loxP), generated with P3 and P4; and (f) lanes 6,7 (targeting construct) using respectively P3 and P4, and P1 and P4. Circled “F”, frt site; large arrowhead, loxP site.











