Synthesis and DNA-binding ability of Spl protein zinc finger domain and its peptidomimetics

The second zinc finger fragment of Sp1 (Spl-ZF2), its mutant (Spl-ZF2/HT. E²⁰→H, R²³→T), and two mimic analogues (ZF20 and ZF15) were synthesized by stepwise solid phase technique. The CD spectra and UV-visible spectrum with CoCl₂ indicated that the formation of zinc finger structure was affected not only by the hy-drophobic amino acids but also by the change of the distance between Cys and His. Gel-retardation electrophoresis as-says indicated that the Grlu and Arg residues are very important for recognition. A single zinc finger like Spl-ZF2 is able to bind DNA sequence specifically.