E3 ubiquitin ligase RNF4, also known as RNF4, contains a RING finger motif and acts as a transcription regulator. This protein has been shown to interact with, and inhibit the activity of, TRPS1, a transcription suppressor of GATA-mediated transcription. Transcription repressor ZNF278/PATZ is found to interact with this protein, and thus reduce the enhancement of androgen receptor-dependent transcription mediated by this protein.