Ferguson ZNF Sandbox: Difference between revisions

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[[Image:Structure.jpg|left|400px]]
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The three-dimensional solution structure of a zinc finger nucleic acid binding motif has been determined by nuclear magnetic resonance (NMR) spectroscopy. Spectra of a synthetic peptide corresponding to a single zinc finger from the Xenopus protein Xfin yielded distance and dihedral angle constraints that were used to generate structures from distance geometry and restrained molecular dynamics calculations. The zinc finger is an independently folded domain with a compact globular structure in which the zinc atom is bound by two cysteine and two histidine ligands. The polypeptide backbone fold consists of a well-defined helix, starting as alpha and ending as 3(10) helix, packed against two beta strands that are arranged in a hairpin structure. A high density of basic and polar amino acid side chains on the exposed face of the helix are probably involved in DNA binding. <ref>PMID:2503871</ref>.
The three-dimensional structure of a zinc finger binding motif has been determined by nuclear magnetic resonance (NMR) spectroscopy. The zinc finger is an independently folded domain with a compact globular structure in which the zinc atom is bound by two cysteine and two histidine ligands. The polypeptide backbone fold consists of a well-defined helix, starting as alpha and ending as 3(10) helix, packed against two beta strands that are arranged in a hairpin structure. A high density of basic and polar amino acid side chains on the exposed face of the helix are probably involved in DNA binding. <ref>PMID:2503871</ref>.


In some zinc finger structures, the His binding residues are replaced by two Cys residues.  In other structures, there are six Cys residues that bind two zinc ions.  In any case, the Zn2+ ions group together into small globular domains, which eliminates the need for larger, hydrophobic protein cores<ref>Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. Fundamentals of Biochemistry: Life at the Molecular Level. 3rd Ed. Hoboken, NJ: Wiley, 2008</ref>.
In some zinc finger structures, the His binding residues are replaced by two Cys residues.  In other structures, there are six Cys residues that bind two zinc ions.  In any case, the Zn2+ ions group together into small globular domains, which eliminates the need for larger, hydrophobic protein cores<ref>Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. Fundamentals of Biochemistry: Life at the Molecular Level. 3rd Ed. Hoboken, NJ: Wiley, 2008</ref>.