The C-terminal loop of the homing endonuclease I-CreI is essential for site recognition, DNA binding and cleavage.

ABSTRACT: Meganucleases are sequence-specific endonucleases with large cleavage sites that can be used to induce efficient homologous gene targeting in cultured cells and plants. These enzymes open novel perspectives for genome engineering in a wide range of fields, including gene therapy. A new crystal structure of the I-CreI dimer without DNA has allowed the comparison with the DNA-bound protein. The C-terminal loop displays a different conformation, which suggests its implication in DNA binding. A site-directed mutagenesis study in this region demonstrates that whereas the C-terminal helix is negligible for DNA binding, the final C-terminal loop is essential in DNA binding and cleavage. We have identified two regions that comprise the Ser138-Lys139 and Lys142-Thr143 pairs whose double mutation af

SUBMITTER: Prieto J 

PROVIDER: S-EPMC1904291 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature