Patent ID: 7531353

Claim:
A retroviral vector which undergoes promoter conversion comprising in 5′ to 3′ order, (a) a 5′ long terminal repeat region of the structure U3-R-U5; (b) one or more coding sequences, said sequences being inserted into the body of the vector; and (c) a 3′ long terminal repeat region comprising a partially deleted U3 region into which a polylinker sequence containing a heterologous promoter has been inserted, wherein after infection of a target cell, said U3 of said 5′ long terminal repeat region is replaced by said partially deleted U3 region and said heterologous promoter, resulting in said one or more coding sequences becoming operatively linked to said heterologous promoter and said heterologous promoter regulating expression of said one or more coding sequences in said target cell, and further wherein each long terminal repeat region is derived from a retrovirus selected from the group consisting of Murine Leukemia Virus, Mouse Mammary Tumor Virus, Murine Sarcoma Virus, Simian Immunodeficiency Virus, Human Immunodeficiency Virus, Human T Cell Leukemia Virus, Feline Immunodeficiency Virus, Feline Leukemia Virus, Bovine Leukemia Virus, Mason-Pfizer-Monkey Virus, and combinations thereof.