This is a zinc finger domain C2H2 which can be found in optineurin (optic neuropathy inducing protein) and NF-kappa-B essential modulator (NEMO) furthermore, it can be found in kinase TBK1, a member of the IKK (inhibitor of nuclear factor kappa-B kinase) family. The C-terminal region, which carries the zinc finger domain, constitutes the regulatory domain of NEMO, as it receives the activation signal from upstream molecules, and subsequently transmits this activation to the kinases bound to the N-terminal domain. The isolated NEMO zinc finger is thought to be involved in protein-protein rather than protein-DNA interaction [1].

1: Solution structure of NEMO zinc finger and impact of an anhidrotic ectodermal dysplasia with immunodeficiency-related point mutation. Cordier F, Vinolo E, Veron M, Delepierre M, Agou F; J Mol Biol. 2008;377:1419-1432. PMID:18313693