RNF4 Human

Ring Finger Protein 4 (RNF4), also known as Small Nuclear Ring Finger Protein (SNURF), is a protein encoded by the RNF4 gene in humans. This protein is characterized by the presence of a RING finger domain, which is a specialized type of zinc finger that mediates protein-protein interactions. RNF4 functions primarily as an E3 ubiquitin ligase, playing a crucial role in the ubiquitination process, which tags proteins for degradation by the proteasome .

RNF4 contains a RING finger motif and four SUMO interaction motifs (SIMs) at the N-terminal. The RING domain is located at the C-terminal. The SIM domains have a preference for binding polySUMO chains, and RNF4 functions to ubiquitinate polysumoylated proteins, including promyelocytic leukemia protein (PML) .

As a transcription regulator, RNF4 interacts with and inhibits the activity of TRPS1, a transcription suppressor of GATA-mediated transcription. Additionally, RNF4 interacts with transcription repressor ZNF278/PATZ1, reducing the enhancement of androgen receptor-dependent transcription mediated by RNF4 .

RNF4 is broadly expressed at low levels in many tissues but is highly expressed in the testis. It is found in various cellular components, including the cytoplasm, PML body, nucleoplasm, and nucleus .

RNF4 plays a significant role in several biological processes, including:

• Androgen receptor signaling pathway
• Regulation of transcription, DNA-templated
• Protein ubiquitination
• Response to arsenic-containing substances
• Regulation of kinetochore assembly
• Proteasome-mediated ubiquitin-dependent protein catabolic process

Studies of the mouse and rat counterparts of RNF4 suggest a role in spermatogenesis .

Recombinant human RNF4 is produced in Escherichia coli (E. coli) and is available as a single, non-glycosylated polypeptide chain containing 213 amino acids. It has a molecular mass of 23.7 kDa and is fused to a 23 amino acid His-tag at the N-terminus. The recombinant protein is purified using proprietary chromatographic techniques .

Recombinant RNF4 is used in various laboratory research applications, including studies on protein ubiquitination, transcription regulation, and androgen receptor signaling. It is also valuable in understanding the molecular mechanisms underlying diseases related to these processes .