E3 ubiquitin-protein ligase RBX1 is a ~12 kDa protein. E3 ubiquitin ligase component of multiple cullin-RING-based E3 ubiquitin-protein ligase (CRLs) complexes which 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. CRLs complexes and ARIH1 collaborate in tandem to mediate ubiquitination of target proteins, ARIH1 mediating addition of the first ubiquitin on CRLs targets. The functional specificity of the E3 ubiquitin-protein ligase complexes depends on the variable substrate recognition components. As a component of the CSA complex mediates ubiquitination of Pol II subunit POLR2A at 'Lys-1268', a critical TC-NER checkpoint. Core component of the Cul7-RING(FBXW8) ubiquitin ligase complex, which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. 2. Kamura, T. et al. (1999) Genes & development 13, 2928-33. PMID: 105799994. Zhang, DD. et al. (2005) The Journal of biological chemistry 280, 30091-9. PMID: 159830466. Cen, B. et al. (2009) The Journal of biological chemistry 284, 5265-76. PMID: 191121777. Isobe, T. et al. (2009) The Journal of biological chemistry 284, 27766-27779. PMID: 196796649. Beck, J. et al. (2013) Nature cell biology 15, 430-9. PMID: 23455478 | 
