Cys2His2 zinc finger DNA-binding domain (C2H2-ZNF)

The Cys2His2 (C2H2) zinc finger DNA-binding domain is the most common DNA-binding motif found in eukaryotic transcription factors, characterized by a consensus sequence where a zinc ion is coordinated by two cysteine and two histidine residues (UniProt: PRO_0000044506). These domains typically consist of an alpha-helix and a two-stranded beta-sheet, where the alpha-helix inserts into the major groove of the DNA to recognize specific nucleotide triplets (PubMed: 15718139). Beyond DNA binding, C2H2 domains can also mediate RNA binding and protein-protein interactions, making them versatile regulators of gene expression and cellular signaling (PubMed: 23395138). In therapeutic contexts, C2H2 domains have been extensively engineered to create Zinc Finger Nucleases (ZFNs) for precision genome editing and artificial transcription factors for gene modulation (PubMed: 20871606). Dysregulation or mutation of proteins containing these domains is linked to various pathologies, including oncogenesis, where they may act as either activators or repressors of tumor-related genes (PubMed: 28231538). While highly specific, the primary challenge in targeting or utilizing these domains remains the risk of off-target effects and the complexity of designing domains for non-canonical DNA sequences.

Other names

C2H2 zinc fingerKrüppel-type zinc fingerClassical zinc fingerZinc finger C2H2-typeCys2-His2 zinc finger

Engineered C2H2-ZNF domains are used in Zinc Finger Nucleases (ZFNs) to induce site-specific double-strand breaks for gene editing (PubMed: 20871606). Small molecules can also disrupt the coordination of the zinc ion or compete for DNA binding sites (PubMed: 15575857).