The Tnfsf4 cDNA, amplified from mRNA isolated from spleens of C57BL/6J mice, was placed under control of the ubiquitously expressed metallothionein promoter followed by the hemoglobin beta IVS intron.
The 3' end of the cDNA, without its polyadenylation signal, was joined to a fragment of the human growth hormone gene, which distinguishes transgene-derived from endogenous transcripts. Transgenic mice express 4- to 250-fold higher levels, depending on tissue type, of transgenic mRNA than do nontransgenic littermates in liver, aorta, heart and spleen.