The genomic organization of the murine Pax 8 gene and characterization of its basal promoter

lambda phage clones containing the murine Pax 8 gene were isolated from a C57BL/6 kidney genomic mouse Library using mouse cDNA fragments as probes. A clone encompassing about 16 lib of the 5' untranslated region of the murine Pax 8 gene was isolated from a mouse embryonic stem cell (D3) library. The murine Pax 8 gene has a size of approximately 26 kb and contains the coding sequence for mRNA in 12 exons, The major and several minor transcription initiation sites were identified. Position +1 is located 488 nucleotides upstream of the ATG initiation codon and 24 bases downstream of a TATA-like sequence, ATAAAA. The translation initiation and termination sites are located in exons 2 and 12, respectively, Further analysis of 570 bases of the 5' flanking sequence revealed AP2, SP1, PEA3, zeste, NF-kappa B, and CCAAT consensus binding sites, Ribonuclease protection assays with a probe spanning the first two exons of mouse Pay 8 cDNA. on total RNA samples isolated from different tissues of newborn mice show tat the murine Pax 8 gene Is predominantly expressed in kidney tissue. Low levels of Pax 8 gene expression were also found in the liver; spleen, lung brain, and heart. The same transcription initiation sites are utilized in different tissues of newborn mice and embryo at Day 10,5 postconception. A FISH assay shows that the murine Pax 8 gene is located on chromosome 2, map position B. (C) 1997 Academic Press.