The transgene construct was designed with a truncated mouse Kdr (kinase insert domain protein receptor) gene, under the control of heptamerized tetracycline operator (tetO; also called tetracycline-responsive element (TRE) or tet-operator) sequences and a cytomegalovirus minimal promoter with a beta-globin poly A signal. The truncated gene encodes amino acids 1 through 828, which includes the cytoplasmic tyrosine kinase domain, and has a hemaglutin (HA) tag fused at the C terminus.This transgene was injected into fertilized FVB/N mouse eggs. Founder line 4377.5 was subsequently established. (J:100427)