How is p53 regulated?
p53 is regulated by an array of posttranslational modifications both during normal homeostasis and in stress-induced responses. More than 36 different amino acids within p53 have been shown to be modified in various biochemical and cell culture studies (Figure 1) (Kruse and Gu, 2008b).
Is p53 a regulatory protein?
The p53 tumor suppressor protein plays a key role in the regulation of the cell cycle and cell death. The p53 protein is also involved in cell differentiation, DNA repair, senescence and angiogenesis.
Is p53 regulated by MDM2?
MDM2 negatively regulates p53 by targeting the ubiquitin ligase activity of MDM2. A complementary approach to prevent p53 degradation by MDM2 is to develop agents designed to inhibit the E3 ligase activity of MDM2 directly so as to mimic the effects of ARF or the ribosomal protein L11.
What type of regulator is p53?
p53 is a transcription factor whose activity is promoted by a wide range of stress signals potentially affecting genome integrity and proper cell proliferation; once activated, p53 is capable of coordinating a complex cellular response that leads to cell-cycle arrest, DNA repair, senescence, or programmed cell death.
How does p53 regulate the cell cycle?
P53 forms a homotetrameric transcription factor that is reported to directly regulate ~500 target genes, thereby controlling a broad range of cellular processes, including cell cycle arrest, cell senescence, DNA repair, metabolic adaptation and cell death.
How do I know if my p53 is activated?
p53 activation is monitored using an antibody that detects endogenous levels of p53 that have been phosphorylated on serine residue, 15. This antibody does not recognize p53 that has been phosphorylated on other sites. Phosphorylated p-53 (Ser15) levels are then normalized against total ERK1 protein levels.
What can inhibit p53?
The apoptosis-inducing activity of p53 can also be inhibited by inducing degradation of the p53 protein by cellular or viral proteins such as mdm-2 (34), HPV E6 (35), and adenovirus E1B55 and E4orf6 (36) or by compounds such as the NAD(P)H oxidoreductase 1 inhibitor dicoumarol and hsp90 inhibitors (9–11).
What proteins inhibit p53?
The hepatitis B virus (HBV) HBx and the human T cell lymphotropic virus-1 (HTLV-1) Tax proteins inhibit p53 activity through the modulation of p300/CBP nuclear factors, while the Kaposi’s sarcoma herpesvirus (HHV8) LANA, vIRF-1 and vIRF-3 proteins have been shown to destabilize the oncosuppressor, causing a decrease in …
Which of the following property is not exhibited by a cancerous cell?
Hence, the property which cancer cells does not have is they show contact inhibition.
What 4 Things can activate p53?
A growing number of stress signals that can lead to p53 activation are being identified, including DNA damage, oncogene activation and more. Interestingly, different stress signals seem to utilize different pathways to allow for the activation of p53.