Abstract: This invention relates to a double transgenic animal that simultaneously expresses the gene or the cDNA (complementary DNA) of insulin and the gene or the cDNA (complementary DNA) of glucokinase directed by a promoter or fusion of promoters which permit insulin and glucokinase to be expressed in muscle and its use in the development of therapeutic approximations for diabetes mellitus.

Abstract: The chimeric gene is directed by a promoter or fusion of promoters which preferably are regulable and activated by the diabetic process. Preferably, it is obtained by fusion of the human insulin gene to the promoter of PEPCK (P-enolpiruvate carboxiquinasa). Said promoter (fragment −460 bp to +73 bp) is fused to the flank zone 5′ of the human insulin gene (−170 bp to +1). The gene of the human insulin contains two coding exons E1 and E2 and two introns A and B. It also relates to an expression vector which allows the expression of insulin in cells which are different from the &bgr;-cells of the pancreas, and to a transgenic animal which expresses said chimeric gene. It is especially used for the gene therapy of diabetes.

Abstract: The chimeric gene is directed by a promoter or fusion of promoters which preferably are regulable and activated by the diabetic process. Preferably, it is obtained by fusion of the human insulin gene to the promoter of PEPCK (P-enolpiruvate carboxiquinasa). Said promoter (fragment -460 bp to +73 bp) is fused to the flank zone 5' of the human insulin gene (-170 bp to +1). The gene of the human insulin contains two coding exons E1 and E2 and two introns A and B. It also relates to an expression vector which allows the expression of insulin in cells which are different from the .beta.-cells of the pancreas, and to a transgenic mouse which expresses said chimeric gene.