Tg(Pax4-lacZ)2Pgr

The transgene comprises a 0.5 kb fragment of BALB/c genomic DNA from a region upstream of paired box gene 4 that includes the minimal promoter sequence ligated directly to the lacZ coding sequence. Transgenic embryos express beta-galactosidase in the endocrine pancreas in recapitulation of the cell type- and developmental stage- specific expression of Pax4. The genomic fragment includes a 407 base pair segment that in the genome resides approximately 1.3 kb upstream of the Pax4 transcription start site and that is 88% identical to the orthologous segment from Homo sapiens. This highly conserved region contains target sequences for four transcription factors that regulate pancreatic beta and delta cell-specific gene expression. (J:66530)