RNF4 Background Information The RING finger motif is a specialized DNA-binding zinc finger domain found in many transcriptional regulatory proteins. The ring finger protein (RNF) family includes any protein containing the signature RING finger motif. RNF4, also known as SNURF, is abundantly expressed in human testis and mouse embryo. RNF4 contains a C-terminal RING finger motif and binds linear, super-coiled and four-way junction DNA. RNF4 also interacts with nucleosomes and may promote the assembly of nucleoprotein structures. Ectopically expressed, RNF4 inhibits cell proliferation of germ cell tumor-derived cells, but cysteine-directed mutations in the RING finger motif abolished this growth inhibition activity. RNF4 may act as a transcription activator or a repressor. As a transcriptional activator, RNF4 mediates androgen receptor activity. RNF4 also associates with POZ-AT hook-zinc finger protein (PATZ), and the RNF4/PATZ complex acts as a transcriptional repressor. The gene encoding human RNF4 maps to chromosome 4p16.3.
