DNA recognition and cleavage by the LAGLIDADG homing endonuclease I-CreI.
نویسندگان
چکیده
The structure of the LAGLIDADG intron-encoded homing endonuclease I-CreI bound to homing site DNA has been determined. The interface is formed by an extended, concave beta sheet from each enzyme monomer that contacts each DNA half-site, resulting in direct side-chain contacts to 18 of the 24 base pairs across the full-length homing site. The structure indicates that I-CreI is optimized to its role in genetic transposition by exhibiting long site-recognition while being able to cleave many closely related target sequences. DNA cleavage is mediated by a compact pair of active sites in the I-CreI homodimer, each of which contains a separate bound divalent cation.
منابع مشابه
Metal-dependent DNA cleavage mechanism of the I-CreI LAGLIDADG homing endonuclease.
The LAGLIDADG homing endonucleases include free-standing homodimers, pseudosymmetric monomers, and related enzyme domains embedded within inteins. DNA-bound structures of homodimeric I-CreI and monomeric I-SceI indicate that three catalytic divalent metal ions are distributed across a pair of overlapping active sites, with one shared metal participating in both strand cleavage reactions. These ...
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عنوان ژورنال:
- Molecular cell
دوره 2 4 شماره
صفحات -
تاریخ انتشار 1998