The single Cys2-His2 zinc finger domain of the GAGA protein flanked by basic residues is sufficient for high-affinity specific DNA binding

Proc Natl Acad Sci U S A. 1996 Apr 2;93(7):2822-6. doi: 10.1073/pnas.93.7.2822.


Specific DNA binding to the core consensus site GAGAGAG has been shown with an 82-residue peptide (residues 310-391) taken from the Drosophila transcription factor GAGA. Using a series of deletion mutants, it was demonstrated that the minimal domain required for specific binding (residues 310-372) includes a single zinc finger of the Cys2-His2 family and a stretch of basic amino acids located on the N-terminal end of the zinc finger. In gel retardation assays, the specific binding seen with either the peptide or the whole protein is zinc dependent and corresponds to a dissociation constant of approximately 5 x 10(-9) M for the purified peptide. It has previously been thought that a single zinc finger of the Cys2-His2 family is incapable of specific, high-affinity binding to DNA. The combination of an N-terminal basic region with a single Cys2-His2 zinc finger in the GAGA protein can thus be viewed as a novel DNA binding domain. This raises the possibility that other proteins carrying only one Cys2-His2 finger are also capable of high-affinity specific binding to DNA.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Cloning, Molecular
  • DNA / metabolism*
  • DNA Primers
  • DNA-Binding Proteins*
  • Drosophila / metabolism
  • Drosophila Proteins*
  • Homeodomain Proteins / biosynthesis
  • Homeodomain Proteins / chemistry*
  • Homeodomain Proteins / metabolism*
  • Kinetics
  • Molecular Sequence Data
  • Peptide Fragments / chemistry
  • Peptide Fragments / isolation & purification
  • Peptide Fragments / metabolism
  • Polymerase Chain Reaction / methods
  • Protein Conformation
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Transcription Factors / biosynthesis
  • Transcription Factors / chemistry*
  • Transcription Factors / metabolism*
  • Transfection
  • Zinc Fingers*


  • DNA Primers
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Homeodomain Proteins
  • Peptide Fragments
  • Recombinant Proteins
  • Transcription Factors
  • Trl protein, Drosophila
  • DNA