This is a C2H2 zinc-finger domain found in ZHX proteins such as ZHX1. ZHXs are multidomain proteins comprising two C2H2 zinc finger motifs and five homeodomains. Both homeodomains and zinc fingers are short protein modules involved in protein-DNA and/or protein-protein interactions; they are frequently associated with roles in transcriptional regulation. All members of the ZHX family are reported to be able to form both homo- and heterodimers via the region containing homeodomain 1 [1]. ZHX1 is a transcriptional repressor which is ubiquitously expressed. It interacts with nuclear factor Y subunit A (NFYA) and DNA methyl transferase 3B (DNMT3B) for its repression activity. Changes in expression profiles of rat ZHX1 ortholog have been associated with glomerular disease. In addition to the five homeodomains, ZHX1, which also contains of two N terminal C2H2 zincfingers forms homodimers via homeodomain and can also form heterodimers with ZHX3 [2].

1: Novel structural features in two ZHX homeodomains derived from a systematic study of single and multiple domains. Bird LE, Ren J, Nettleship JE, Folkers GE, Owens RJ, Stammers DK; BMC Struct Biol. 2010;10:13. PMID:20509910

2: Solution NMR structures of homeodomains from human proteins ALX4, ZHX1, and CASP8AP2 contribute to the structural coverage of the Human Cancer Protein Interaction Network. Xu X, Pulavarti SV, Eletsky A, Huang YJ, Acton TB, Xiao R, Everett JK, Montelione GT, Szyperski T; J Struct Funct Genomics. 2014;15:201-207. PMID:24941917