Figure 1.

(A) Efficient modification of a Zipro1 BAC by using R6kγ RecA-based shuttle vector. A 500-bp fragment corresponding to the last exon of the Zipro 1 gene (Yang et al. 1997) and an IRESEGFP marker gene were cloned into pLD53-RecA vector. This shuttle vector was then electroporated into Zipro1 containing BAC169 cells (Yang et al. 1997). Co-integrates were formed via homologous recombination and selected by chloramphenicol and ampicillin. (B) Southern blot analysis of the co-integrate BAC clones. Co-integrates BAC DNA were digested with SpeI and separated by electrophoresis on a 1% agarose gel. The DNA was transferred to nylon membrane, and the blot was analyzed by using the “A Box” as a probe: co-integrate BAC clones (lanes 1–16), wild-type BAC (lane B), and shuttle vector (lane V).