Targeted Sleeping Beauty transposition in human cells.
Transposons are natural gene delivery vehicles. The Sleeping Beauty (SB) transposon shows efficient transposition and long-term transgene expression in the cells of vertebrates including humans. SB transposition into chromosomal DNA occurs in a fairly random manner. This is clearly not desirable in human gene therapeutic applications because there are potential genotoxic effects associated with transposon integration. In this study we set out to manipulate the selection of SB's target sites for targeted transposition into predetermined chromosomal regions. We evaluated experimental strategies based on engineered proteins composed of DNA-binding domains fused to (i) the transposase; (ii) another protein that binds to a specific DNA sequence within the transposable element; and (iii) another protein that interacts with the transposase. We demonstrated targeted transposition into endogenous matrix attachment regions (MARs) and a chromosomally integrated tetracycline response element (TRE) in cultured human cells, using targeting proteins that bind to the transposon DNA. An approach based on interactions between the transposase and a targeting protein containing the N-terminal protein interaction domain of SB was found to enable an approximately 10(7)-fold enrichment of transgene insertion at a desired locus. Our experiments provide proof-of-principle for targeted chromosomal transposition of an otherwise randomly integrating transposon. Targeted transposition can be a powerful technology for safe transgene integration in human therapeutic applications.
Ivics
Zoltán
Z
Max Delbrück Center for Molecular Medicine, Berlin, Germany. zivics@mdc-berlin.de
Katzer
Andrea
A
Stüwe
Eva E
EE
Fiedler
Dora
D
Knespel
Siegne
S
Izsvák
Zsuzsanna
Z
D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004251:DNA Transposable Elements / Q000235:genetics*; D024202:Electrophoretic Mobility Shift Assay; D018014:Gene Transfer Techniques; D015894:Genome, Human / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D019895:Transposases / Q000235:genetics / Q000378:metabolism
D004251:DNA Transposable Elements; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D004247:DNA; D019895:Transposases