Patent ID: 6866997

Claim:
A method for preparing a nucleic acid binding protein that binds to a target nucleotide sequence, wherein the binding protein comprises a plurality of zinc fingers of the Cys2-His2 class, wherein the method comprises: i) selecting a quadruplet within the target nucleotide sequence; ii) designing the binding protein such that binding of a zinc finger to the quadruplet is obtained by choosing the sequence of particular residues of the zinc finger depending on the nucleotide sequence of the quadruplet, as follows: a) if base 4 in the quadruplet is A, then position +6 in the α-helix is Gln and position ++2 is not Asp; b) if base 4 in the quadruplet is C, then position +6 in the α-helix may be any residue, as long as position ++2 in the α-helix is not Asp; iii) synthesizing a polynucleotide encoding the binding protein of (ii); iv) introducing the polynucleotide of (iii) into a cell; and v) incubating the cell under conditions in which the encoded nucleic acid binding protein is expressed.