Genomic Organization of the Human Arpp Gene

A novel ankyrin-repeated protein, Arpp, is specifically expressed in skeletal and cardiac muscles. Arpp protein is homologous, in its amino acid sequences (52.7% identity), to Carp protein which is proposed to be a putative genetic marker for cardiac hypertrophy. In this study, we isolated the human Arpp gene by screening a human genomic library and analyzed the genomic structure and its 5' flanking region. The Arpp gene was found to encompass a sequence of 11 kb and to consist of 9 exons. The translational initiation site and the stop codon were found to be located at exon 1 and exon 9, respectively. Each exon from 5 to 8 was found to encode 1 of the 4 ankyrin-like domains, respectively. The 2.7 kb upstream of exon 1 was sequenced. The TATA box was identified 29 bp upstream of the transcriptional start site, and multiple putative regulatory elements including the E box and upstream stimulating factor-1 were distributed within the proximal promoter regions. Since these elements were also found in the promoter region of the mouse Arpp gene, they may play an important role in the transcriptional regulation of both human and murine Arpp genes.