The transgene comprises a wild-type mouse phospholamban cDNA that contains 13 bp of 5' untranslated sequence, the entire coding region and 434 bp of 3' untranslated sequence, including the first endogenous polyadenylation site, followed by an SV40 polyadenylation signal and driven by the 5.5 kb cardiac-specific alpha myosin heavy chain (myosin, heavy polypeptide 6, cardiac muscle, alpha) promoter. Northern blot analysis revealed cardiac expression of the 1.0 kb transcript from the transgene, and quantitative immunoblot analysis demonstrated overexpression of phospholamban protein in the hearts of transgenic mice.