This is a family of primate-specific Ret finger protein-like (RFPL) zinc-fingers of the C3HC4 type. Ret finger protein-like proteins are primate-specific target genes of Pax6, a key transcription factor for pancreas, eye and neocortex development [1]. This domain is likely to be DNA-binding [2]. This zinc-finger domain together with the RDM domain, Pfam:PF11002, forms a large zinc-finger structure of the RING/U-Box superfamily. RING-containing proteins are known to exert an E3 ubiquitin protein ligase activity with the zinc-finger structure being mandatory for binding to the E2 ubiquitin-conjugating enzyme [3].

1: Evolutionary Forces Shape the Human RFPL1,2,3 Genes toward a Role in Neocortex Development. Bonnefont J, Nikolaev SI, Perrier AL, Guo S, Cartier L, Sorce S, Laforge T, Aubry L, Khaitovich P, Peschanski M, Antonarakis SE, Krause KH; Am J Hum Genet. 2008; [Epub ahead of print] PMID:18656177

2: Primate-specific RFPL1 gene controls cell-cycle progression through cyclin B1/Cdc2 degradation. Bonnefont J, Laforge T, Plastre O, Beck B, Sorce S, Dehay C, Krause KH; Cell Death Differ. 2011;18:293-303. PMID:20725088

3: RING domain E3 ubiquitin ligases. Deshaies RJ, Joazeiro CA; Annu Rev Biochem. 2009;78:399-434. PMID:19489725