RBX1
RBX1 (ring-box 1, also known as ROC1 or RNF75) is the RING-box subunit of cullin-RING E3 ubiquitin ligase complexes. It directs the ubiquitination and proteasomal degradation of substrates involved in cell cycle progression, signal transduction, transcription and DNA repair. Browse Assay Genie's current range of RBX1 research reagents below, or read on for the biology behind the target.
RBX1 is an E3 ubiquitin ligase component of multiple cullin-RING-based E3 ubiquitin-protein ligase (CRL) complexes. These complexes mediate the ubiquitination and subsequent proteasomal degradation of target proteins, including proteins involved in cell cycle progression, signal transduction, transcription and transcription-coupled nucleotide excision repair. Functional specificity depends on the variable substrate recognition components of each complex. RBX1 recruits the E2 ubiquitin-conjugating enzyme CDC34 and brings it into close proximity to the substrate, and it probably also stimulates CDC34 autoubiquitination. CRLs and ARIH1 act in tandem, with ARIH1 adding the first ubiquitin to CRL targets. RBX1 also promotes the neddylation of cullins through its interaction with UBE2M.
RBX1 is a core subunit in several defined complexes. It is part of the CSA complex, which ubiquitinates the Pol II subunit POLR2A at Lys-1268, a critical TC-NER checkpoint. It is a core component of the Cul7-RING(FBXW8) ligase and of a Cul9-RING ligase made up of CUL9 and RBX1, which mono-ubiquitinates p53/TP53. With elongin BC, elongin A and CUL5, it polyubiquitinates monoubiquitinated POLR2A. With ATF2 and CUL3, it promotes degradation of KAT5, which attenuates the ability of KAT5 to acetylate and activate ATM. RBX1 is also involved in the ubiquitination of KEAP1, ENC1 and KLHL41, and may be needed for histone H3 and H4 ubiquitination after ultraviolet exposure and for subsequent DNA repair.
The RBX1 gene encodes a RING finger-like domain-containing protein of the RING-box family. The protein is found in the cytoplasm and nucleus. HGNC classifies it among ring finger proteins, SCF complex core subunits and degenerate RING E3 ubiquitin ligases. Other names include ROC1, RNF75 and BA554C12.1. According to NCBI Gene, related pseudogenes exist on chromosomes 2 and 5, and the protein may also affect protein turnover. The mouse ortholog is Rbx1.
RBX1 is a core subunit of cullin-RING ligases that drive ubiquitination and proteasomal degradation of target proteins.
RBX1 interacts with cullin proteins and likely supports the ubiquitination processes needed for cell cycle progression.
As part of the CSA complex, RBX1 ubiquitinates POLR2A at a critical TC-NER checkpoint, and it may support histone ubiquitination after UV exposure.
RBX1 promotes cullin neddylation through UBE2M and forms a Cul9-RING ligase that mono-ubiquitinates p53/TP53.
RBX1 is the RING-box component of multiple cullin-RING E3 ubiquitin ligase complexes. It recruits the E2 enzyme CDC34 close to the substrate, promotes cullin neddylation via UBE2M, and so enables ubiquitination and proteasomal degradation of proteins in the cell cycle, transcription, signalling and DNA repair.
RBX1 stands for ring-box 1. Its aliases and previous symbols are ROC1, RNF75 and BA554C12.1, and UniProt names the protein E3 ubiquitin-protein ligase RBX1. These names can all appear in the literature, so searching with several of them helps.
The mouse ortholog is Rbx1. NCBI Gene reports related pseudogenes on chromosomes 2 and 5. Cross-species use of any reagent should be confirmed, so check the datasheet of any product for its validated reactivity.
Cullin scaffolds, E2 enzymes, substrates and other partners of RBX1 in cullin-RING ligase complexes.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P62877; product specifications from Assay Genie datasheets.