This is the chimeric minigene construct used in many of our transgenic animals. It is composed of the promoter/enhancer region of the C. elegans unc-54 major body wall myosin gene, a synthetic signal peptide, the coding region from a human APP cDNA encoding the 42 amino acid beta-peptide sequence, an engineered stop codon, and the unc-54 3' untranslated region. (See Link, 1995 for details). The construction of this minigene employed expression vectors developed by Andrew Fire (Carnegie Institute of Washington, Baltimore, MD).