Zinc finger proteins are a type of protein characterized by their ability to bind to DNA, RNA, or other proteins through the presence of one or more zinc finger motifs. These motifs typically consist of zinc ions coordinated by cysteine and histidine residues, allowing the protein to adopt a specific structural conformation that facilitates its interaction with nucleic acids. They play a crucial role in regulating gene expression and are involved in various biological processes, making them significant in the context of metal ions in biological systems.