A genetic approach to analysis of transposons.

Integration of the tetracycline resistance transposon Tn10 into lacI of a lacI-lacZ gene fusion permits the isolation of deletions that excise DNA from one end of Tn10 and fuse Tn10 genes with lacZ in such a manner that chimeric proteins with beta-galactosidase activity are produced. The synthesis of the chimeric proteins is under the same control as the transposon genes. Thus, regulation of expression of Tn10 genes can be investigated by measuring beta-galactosidase activity. Analysis of Tn10-lacZ fusions revealed different deletion endpoints within Tn10; lacZ has been fused to at least three different Tn10 genes or operons. Two of these genes are under the control of a tetracycline repressor.