We have developed a hybrid vector that combines the high transduction efficiency of a gene-deleted adenoviral vector and the integration machinery of the bacteriophage-derived integrase PhiC31 for stable transduction and limited integration sites. We based our system on a two-vector system in which the transgene expression cassette is circularized from a helper-dependent vector by Flp-mediated ...

Gene targeting provides a powerful tool for dissecting gene function. However, repeated targeting of a single locus remains a practice mostly limited to unicellular organisms that afford simple targeting methodologies. We developed an efficient method to repeatedly target a single locus in Drosophila. In this method, which we term "site-specific integrase mediated repeated targeting" (SIRT), an...

The integrase from the Streptomyces phage phiC31 carries out efficient recombination between the attP site in the phage genome and the attB site in the host bacterial chromosome. In this paper, we show that the enzyme also functions in human cells. A plasmid assay system was constructed that measured intramolecular integration of attP into attB. This assay was used to demonstrate that in the pr...

Background: PhiC31 integrase is a DNA site-specific recombinase integrates DNA into the chromosomes between the two sites of attB and attP. Several pseudo attPs have been identified in mammalian genomes with critical features for long-term expression of transgene. In this manuscript, we report a novel intrinsic pseudo attP site named CHOL1 in the Chi...

Gene transfer allows transient or permanent genetic modifications of cells for experimental or therapeutic purposes. Gene delivery by HIV-derived lentiviral vector (LV) is highly effective but the risk of insertional mutagenesis is important and the random/uncontrollable integration of the DNA vector can deregulate the cell transcriptional activity. Non Integrative Lentiviral Vectors (NILVs) so...

We have used the phiC31 integrase to introduce large DNA sequences into a vertebrate genome and measure the efficiency of integration of intact DNA as a function of insert size. Inserts of 110 kb and 140 kb in length may be integrated with about 25% and 10% efficiency respectively. In order to overcome the problems of constructing transgenes longer than approximately 150 kb we have established ...

To reveal the full potential of human pluripotent stem cells, new methods for rapid, site-specific genomic engineering are needed. Here, we describe a system for precise genetic modification of human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). We identified a novel human locus, H11, located in a safe, intergenic, transcriptionally active region of chromosome 22, as t...