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1a1l
From Proteopedia
ZIF268 ZINC FINGER-DNA COMPLEX (GCAC SITE)
Overview
BACKGROUND: Zinc fingers of the Cys2-His2 class comprise one of the largest families of eukaryotic DNA-binding motifs and recognize a diverse set of DNA sequences. These proteins have a relatively simple modular structure and key base contacts are typically made by a few residues from each finger. These features make the zinc finger motif an attractive system for designing novel DNA-binding proteins and for exploring fundamental principles of protein-DNA recognition. RESULTS: Here we report the X-ray crystal structures of zinc finger-DNA complexes involving three variants of Zif268, with multiple changes in the recognition helix of finger one. We describe the structure of each of these three-finger peptides bound to its corresponding target site. To help elucidate the differential basis for site-specific recognition, the structures of four other complexes containing various combinations of these peptides with alternative binding sites have also been determined. CONCLUSIONS: The protein-DNA contacts observed in these complexes reveal the basis for the specificity demonstrated by these Zif268 variants. Many, but not all, of the contacts can be rationalized in terms of a recognition code, but the predictive value of such a code is limited. The structures illustrate how modest changes in the docking arrangement accommodate the new sidechain-base and sidechain-phosphate interactions. Such adaptations help explain the versatility of naturally occurring zinc finger proteins and their utility in design.
About this Structure
1A1L is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
High-resolution structures of variant Zif268-DNA complexes: implications for understanding zinc finger-DNA recognition., Elrod-Erickson M, Benson TE, Pabo CO, Structure. 1998 Apr 15;6(4):451-64. PMID:9562555 Page seeded by OCA on Fri May 2 09:40:13 2008
