The disclosure provides methods and compositions for the integration (insertion) of a donor DNA molecule into a target DNA molecule. In general, the methods include contacting a target DNA molecule with a linear donor DNA molecule and a Cas 1 protein, where the target DNA molecule includes an AT-rich region (e.g., in some cases positioned 5 and within 50 nucleotides of a region that forms a DNA cruciform structure), where the contacting is not in a bacterial or archaeal cell (e.g., the contacting is in vitro outside of a cell, inside of a eukaryotic cell, etc.), and provides for integration of the donor DNA molecule into the target DNA molecule.
