Zinc-coordinating DNA-binding domains C2HC zinc finger factors CLASSLINK:http\://www.edgar-wingender.de/class 2.7.html Class Class description: The individual zinc finger modules of this class are characterized by a tetrahedrical coordination of one zinc ion by three cysteines and one histidine, arranged according to the pattern C-X(2,4)-C-X(12)-H-(3,5)-C, similar to C2H2 zinc fingers. In contrast to them, they form a rather irregular, but compact structure without recognizable secondary structure elements. At least some C2HC zinc fingers bind sequence-specifically to DNA, where the whole C2HC zinc finger sites in the major groove. (PMID 14744132, PMID 18073212) – This class should not be mixed up with CCHC zinc fingers, which follow the signature C--C----H----C (i.e., having much shorter spacing between the leading two C and the H), and are mostly RNA-binders.