STRUCTURE OF THE MOUSE SERUM AMYLOID-A5 (SAA5) GENE - RELATIONSHIP TOOTHER MEMBERS OF THE SERUM AMYLOID-A FAMILY

The mouse and human genes which encode the serum amyloid A (SAA) prote ins have been extensively characterized, In the present study, the aut hors report the sequencing of the constitutively expressed mouse Saa5 gene, including approximate to 2 kilobases of promoter sequence which extends into the sequence of the adjacent Saa4 pseudogene. The Saa5 ge ne was thus determined to have a 4 exon/3 intron structure, with a B2 repeat located approximate to 450 base pairs upstream, and a microsate llite contained within intron 2. Analyses of Saa5 intronic and promote r sequences, by comparison with representative members of the mouse Sa a and human SAA families, provided evidence which strongly suggests th at mouse Saa5 and the constitutively expressed human SAA4 gene are evo lutionary and functional homologues. Furthermore, putative transcripti on motifs were identified within the Saa5 and SAA4 promoters which may account, in part, for the constitutive expression and unique inductio n profiles of these genes.