Optimized non-canonical zinc finger proteins

摘要

Patent No. 597995 Disclosed is a zinc finger protein comprising a non-C2H2 zinc finger, wherein the non-C2H2 zinc finger has a helical portion involved in DNA binding and wherein at least one zinc finger comprises the sequence Cys-(XA)2-4-CYS-(XB)12-His-(XC)3-5-Cys-(XD)1-10, where XA, XB, XC and XD can be any amino acid and wherein (i) the zinc finger protein is engineered to bind to a target sequence; (ii) (XD)1-10 comprises an amino acid sequence selected from the group consisting of QKP, QLV, and a G residue immediately C-terminal to the C-terminal Cys residue; (iii) when (XD)1-10 comprises the amino acid sequence QKP and (XC)3-5 consists of 3 amino acids, the residues of (XC)3-5 are selected from the group consisting of IRT, IRR, TKI and AQR; and (iv) the sequence is not HAQRCG. Also disclosed is a method for targeted cleavage of cellular chromatin in a plant cell, the method comprising expressing a pair of fusion proteins comprising said zinc finger protein.