Methods of repressing expression of a recombinant
gene in a
cell are provided. The methods include the steps of introducing a
transposase DNA binding motif into or adjacent to the
gene, and introducing into the
cell a
transposase that is capable of binding to the
transposase DNA binding motif. Methods of producing a
population of cells of an
organism that vary in their expression of a
gene are also provided. The methods involve transfecting the cells with a first
polynucleotide sequence encoding the
target gene operably linked to a
promoter such that the
target gene is expressed in the cells, wherein the vector has at least one transposase
DNA binding motif within or adjacent to the
target gene; and transfecting some of the cells with a second
polynucleotide encoding the transposable element operably linked to a second
promoter such that the transposable element is expressed in the cells. In these methods, the target gene in the cells transfected with the second
polynucleotide exhibits reduced expression when compared to the target gene in the cells that are not transfected with the second polynucleotide. Kits having a first polynucleotide with a gene and
a DNA transposase binding motif in or adjacent to the gene, and a second polynucleotide comprising a gene encoding a transposase that is capable of binding to the transposase
DNA binding motif are also provided.