Tg(CD4-TKdelta)2Kzmn

Mice with this transgene express a truncated human Herpes simplex 1 (HSV1) thymidine kinase gene (TK) under control of a 2.1 kb fragment of the EpCD4 plasmid containing three tandem copies of the mouse Cd4 enhancer followed by the human CD4 promoter, without the silencer element, which drives expression in both CD4+ and CD8+ T cells. The 1-kb TK sequence begins just upstream of the second (of four) ATG translation start codons; the endogenous TK polyadenylation signal (poly[A]) has been replaced by the 0.8-kb SV40 poly[A]. Elimination of the TK upstream start sites removes a putative testis-specific enhancer and abrogates expression of TK in the testes. (J:123437, J:128760, J:183380)