exon1 and exon2 of insulin gene were fused to provide enhanced downstream gene function in plasmids at the transcriptional level fusion of insulin mrna upregulated downstream gene expression to such a high level that they mimicked normal insulin mrna level in normal islet beta cells utmd was then used to deliver the insulin gene fusion plasmid under control of the rat insulin promoter driving to intact islets of adult living animals thereby providing a safe tissue specific highly efficient and regulated gene expression for diabetic gene therapy materials and methods rat insulin promoters and plasmids constructs rat insulin gene 1 promoter fragments rip2 1 u2212 412 to u2212 303 rip1 1 u2212 412 to u2212 1 rip4 1 u2212 412 to 43 rip3 1 u2212 412 to 165 genbank accession no j00747 which is defined herein as seq id no 1 and genbank accession no nc 000011 for the human insulin promoter u2014 defined as seq id no 2 both incorporated herein by reference were amplified from sprague dawley sd rat dna using pcr rip forward primers 5 u2032 g ctg agc taa gaa tcc a 3 u2032 seq id no 3 rip2 1 reverse primer 5 u2032 ctgagc attttccacc 3 u2032 seq id no 4 rip1 1 reverse primer 5 u2032 gggagttactgggtctcca 3 u2032 seq id no 5 rip4 1 reverse primer 5 u2032 gcagaattcctgcttgctgatggtcta 3 u2032 seq id no 6 rip3 1 reverse primer 5 u2032 gttggaacaatgacctgga 3 u2032 seq id no 7 and reverse primer 5 ggcagaaggacagtgatct 3 seq id no 8 containing a kpni and xho1 restriction site respectively the sequences of these primers.