Figure 2. Targeting vector design.

(A) shows the targeting vector used to replace the 5′ flanking region of the mouse Avpr1a gene with corresponding sequences from the prairie vole. We generated three targeting vectors that were identical except for the microsatellite region they contained, which is indicated by the cross hatched region. Triangles denote loxP sites. (B) shows hybridization of the external Southern probe in correctly targeted recombinants for all three lines. Because the Acc651 site used to screen for recombinant stem cells was located within the floxed region, excision of the NeoR also resulted in the recombinant allele yielding a ∼9.5 kb band when detected with the external probe. (C) shows PCR genotyping. All three lines were backcrossed to a C57Bl/6J background for at least 5 generations prior to neuroanatomical and behavioral experiments.