Table 1.

Effectors That Interact With MDM2

ProteinsEffect on MDM2MDM2 Localizationp53 DependencyPhysiological Interaction MeasuredReferences
Self Ubp53 Ubp53 Stability or Activity
ARFdowndownupNucleolar relocalization of MDM2 by ARF may not be essential for p53 stabilization.ARF binds MDM2 independent of p53.No(31–41)
L11N.E.N.E.upL11 causes nucleolar relocalization of MDM2.N.E., but L11 and p53 bind to different regions on MDM2.Yes(42)
MDM4Up but polyubiquitination was inhibitedvariesStable but activity downMDM4 inhibits MDM2-mediated degradation and nuclear export of p53.p53-independent interactionYes(110–116)
P300/CBPN.E., but p300 stabilizes Mdm2updownp300 recruits Mdm2 to nuclear body-like structure.p300 binds p53 and/or Mdm2 independently.Yes(57–61)
PI3K/aktN.E.updownPI3K/akt promotes MDM2 from cytoplasm to nucleus.p53-independent interactionYes(47–50)
Tsg101downN.E.downN.E.p53-independent interactionNo(62, 63)
Ubc9/Sumo1downupdownN.E.p53-independent interactionNo(64–66)
Cyclin G/PP2AN.E.N.E.downN.E.p53-independent interactionNo(54–56)
HIF-1αN.E.downupHIF-1α protects nuclear export of p53 by Mdm2.HIF-1α binds p53 independently but enhances in vivo association of p53 and HIGF-1α .No(43)
ATMN.E.N.E.upATM impairs nuclear export of p53 by MDM2.MDM2 phosphorylation is p53 independent.Yes(44–46)
CK2N.E.N.E.Slightly downN.E.N.E.No(67, 68)
  • Ub: ubiquitination. N.E.: not examined.