Abstract
Two different genes, coding for the hormonally regulated rat liver protein .alpha.2u globulin, were introduced into mouse Ltk- cells through cotransfection with the HSV-1 [herpes simplex virus type 1] thymidine kinase gene. Copies of the .alpha.2u globulin genes [3-10] were detected in several tk+ clones, over 50% of which could be induced with dexamethasone to produce .alpha.2u globulin mRNA and protein. The information necessary for hormonal response evidently is contained in the DNA fragment used for transfer.