DNA Zinc finger Recognition helix (a) 2012 Pearson Education,Inc. Eukaryotic DNA binding proteins substructures. (a)The zinc finger structure锌指结构.The amino acids holding the Zn2+ion always include at least two cysteine residues(C)with the other residues being histidine(H).a-Helices are represented by cylinders.)与Zn2+结合的常有两个半胱氨酸和组氨酸残基Eukaryotic DNA binding proteins substructures. (a)The zinc finger structure锌指结构. The amino acids holding the Zn2+ ion always include at least two cysteine residues (C) with the other residues being histidine (H).( -Helices are represented by cylinders. )与Zn2+ 结合的常有两个半胱氨酸和组氨酸残基