Genomic characterization of the mouse inhibitor of apoptosis protein 1 and 2 genes.

Genomic and cDNA clones encoding mouse inhibitor of apoptosis protein 1 and 2 (Miap1 and Miap2) were isolated and characterized. The genes encoding the 602-amino-acid MIAP1 protein and the 612-amino-acid MIAP2 protein are contained within a 57-kb locus in a tandem head-to-tail arrangement. The Miap1 gene consists of nine exons spanning 24 kb, and the Miap2 gene consists of seven exons spanning 21 kb. Fluorescence in situ hybridization analysis mapped the locus to chromosome 9A2, which is syntenic with portions of the human 11q22-q23 region containing the human homologues HIAP1 and HIAP2. Sequencing of the complete Miap1 and Miap2 cDNAs revealed an unusually long 5' untranslated region in the Miap2 transcript, which may indicate nonscanning ribosomal initiation of translation.