RBX1
Description
The RBX1 (ring-box 1) is a protein-coding gene located on chromosome 22.
RBX1 is a human gene that encodes an evolutionarily conserved protein that interacts with cullins. This protein plays a crucial role in the ubiquitination process by forming a heterodimer with cullin-1, facilitating ubiquitin polymerization. RBX1 also contributes to protein turnover regulation.
RBX1 is a crucial component of multiple cullin-RING-based E3 ubiquitin ligase (CRL) complexes. These complexes play a vital role in targeting proteins for ubiquitination and subsequent degradation by the proteasome. CRL complexes are involved in various cellular processes including cell cycle regulation, signal transduction, transcription, and DNA repair. RBX1 collaborates with ARIH1 to initiate ubiquitination, with ARIH1 adding the first ubiquitin. The specificity of each CRL complex depends on its unique substrate recognition components. RBX1 is also a component of the CSA complex, which promotes the degradation of ERCC6, a protein involved in DNA repair. It recruits and positions the CDC34 E2 ubiquitin-conjugating enzyme, potentially stimulating its auto-ubiquitination. RBX1 has been implicated in the ubiquitination of histones H3 and H4 in response to UV damage, contributing to DNA repair. It interacts with UBE2M, promoting the neddylation of CUL1, CUL2, CUL4, and CUL4B, essential for CRL function. RBX1 participates in the ubiquitination of KEAP1, ENC1, and KLHL41, proteins involved in various cellular processes. In conjunction with ATF2 and CUL3, RBX1 promotes the degradation of KAT5, reducing its ability to acetylate and activate ATM, a protein kinase involved in DNA damage response. As part of a multi-subunit complex, RBX1 polyubiquitinates monoubiquitinated POLR2A, a subunit of RNA polymerase II.
RBX1 is also known as BA554C12.1, RNF75, ROC1.
