RING-box protein 1 (RBX1)

RING-box protein 1 (RBX1) is a **conserved E3 ubiquitin ligase component** encoded by the RBX1 gene in humans[1][4]. It is an essential part of the Skp1–Cullin–F-box (SCF) complex (Cullin–RING ligase family), facilitating the transfer of ubiquitin from E2 enzymes to target proteins, thereby marking them for proteasome-mediated degradation[1][4]. RBX1 heterodimerizes with cullin proteins (CUL1, 2, 4A, 5, and 7), forming the catalytic core of E3 ligases involved in regulating protein turnover, cell cycle progression, and genomic stability[1][2][4]. RBX1 activity is critical for normal development, cell division, and cancer cell proliferation; its dysfunction or suppression leads to cell cycle arrest, DNA damage, apoptosis, and developmental lethality in model organisms[2][4]. It is also referred to as ROC1 or Regulator of Cullin 1. Targeting RBX1 or the SCF E3 ligase complex has therapeutic research interest in oncology, but broad inhibition may have significant safety challenges due to RBX1’s fundamental role in cellular homeostasis[4].

Other names

Regulator of cullin 1ROC1Rbx1

Inhibition of SCF (Skp1–Cullin–F-box) E3 ligase activity, Promotion of substrate degradation via the ubiquitin–proteasome pathway