Abstract: Methods are provided for manipulating nucleic acid to produce gene fusions, to delete or clone a portion of a chromosome, or to insert a sequence into a chromosome. The methods employ sequential transposition processes using two or more pairs of inverted repeat transposase-interacting sequences on a transposable polynucleotide wherein each pair of transposase-interacting sequences interacts with a distinct transposase enzyme.

Abstract: Transposase proteins that are modified relative to and have higher transposase activities than the wild-type Tn5 transposase are disclosed. A transposase protein of the present invention differs from the wild-type Tn5 transposase at amino acid position 41, 42, 450, or 454 and has greater avidity than the wild-type Tn5 transposase for at least one of a Tn5 outside end sequence as defined by SEQ ID NO:3, a Tn5 inside end sequence as defined by SEQ ID NO:4, and a modified Tn5 outside end sequence as defined by SEQ ID NO:5. Also disclosed are various systems and methods of using the transposase proteins of the present invention for in vitro or in vivo transposition.

Abstract: The present invention discloses a nucleic acid cleavage assay for members of the transposase/integrase superfamily. A method of using the assay to screen for modulators of the nucleic acid cleavage activity is also disclosed. The present invention further provides a method for screening for modulators of binding of a transposase/integrase to its corresponding recognition sequence. In addition, the present invention provides a method of identifying a modulator for a particular transposase/integrase such as HIV integrase based on modulators of other members of the transposase/integrase superfamily. Also disclosed are Tn5 transposase inhibitors and HIV integration inhibitors.