Somatic cell gene transfer by direct injection into adult heart

he direct injection of plasmid DNA into adult muscle tissue is an effective means of somatic cell gene transfer. This technique was used to study gene regulation in cardiac muscle tissue. Prior to the description of the studies, the protocols for generating milligram quantities of pure DNA for cardiac injection and for consistent detection of reporter gene activity in tissue extracts are described.;In contrast to MCK sequences, ;A method of modulating gene expression from a viral regulatory element was also tested by the direct injection technique. A plasmid that expressed the YY1 transcription factor repressed expression from a target plasmid containing the luciferase reporter gene under the control of the long terminal repeat (LTR) sequence from the Rous sarcoma virus. This finding shows that the expression of directly injected genes in adult heart can be regulated in trans by the co-injection of transcription factor genes.;The creatine kinase-M (MCK) enhancer contains many regulatory elements and is required for high level gene expression in skeletal muscle tissue. In order to determine whether one such element, the E-box, is required for MCK expression in cardiac tissue, the rabbit MCK enhancer and promoter sequences were fused to a luciferase reporter gene and injected into skeletal and cardiac muscle tissues. The enhancer was required for skeletal muscle expression, but a CArG box sequence at position...