[Genomic organization and promoter analysis of mouse apoptosis signal-regulating kinase 2 (ASK 2)]

ASK 2/MAPKKK 6 was identified as a member of the MAPKKK family, which shares 45% amino acid identity with ASK 1/MAPKKK 5. In this study, the genomic organization and promoter of mouse ASK 2 were determined. ASK 2 gene spans approximately 12 kb and is comprised of 29 exons, flanked by 5' regulatory regions. Through comparison with ASK 2 cDNA variant clones, two splice variants were identified: a transcript lacking 24 bases encoding 8 amino acids was caused by disuse of exon 3, and another frameshifted transcript due to 4 bases deletion was produced by usage of the first 4 bases of exon 17 as a part of the splicing acceptor. Reporter plasmid analysis demonstrated that a promoter existed in the immediate upstream region adjacent to exon 1. Interestingly, the 5'-flanking region of the promoter possessed a strong suppressive element. These results suggest that expression of ASK 2 is regulated by multiple mechanisms.