(A) Nkx2.2hdVP16 mRNA is expressed throughout the pancreatic epithelium at E10.5 (L7319), E12.5 (L7318) and E15.5 (L7318), and is restricted to endocrine cells at E18.5 (L7319). (B) Nkx2.2hdEnR mRNA is detected in the pancreatic epithelium at E10.5, E12.5 and E15.5, and strong expression is detected in the endocrine tissue at E18.5 (all L7414). Both transgenes are expressed in a manner similar to Nkx2.2 throughout development; however, a small amount of transgene expression is detectable in acinar cells. (C) Real-time PCR quantification of Nkx2.2-repressor and Nkx2.2-activator transgene expression compared to endogenous Nkx2.2 expression. Percentages indicate percent transgene expression relative to endogenous Nkx2.2. Nkx2.2hdVP16: line 7319 (n=5), line 7318 (n=4); Nkx2.2hdEnR: line 7414 (n=4), line 7660 (n=3).