Related Experiment Videos
Excision of beta-L- and beta-D-nucleotide analogs from DNA by p53 protein
M Kukhanova1, T W Liu, H Pelicano
1Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Abstract:
The tumor suppressor p53 protein plays a critical role in the cell-cycle progression. The role of the 3'-to-5' exonuclease activity of p53 protein in the DNA repair process remains elusive. Using an in vitro exonuclease assay and defined oligonucleotides terminated with beta-D- and beta-L-nucleoside analogs at the 3'-terminus, we studied the ability of p53 protein to excise beta-L- and beta-D-nucleoside analogs which have anticancer or antiviral potential. p53 protein removes beta-D-nucleoside analogs more efficiently compared to that of beta-L-nucleoside analogs. The affinity of p53 protein for an beta-L-nucleotide terminated primer was 5 fold lower compared to non-modified primer. The hypothesis on an important role of the 3'-to-5' exonuclease activity of p53 protein in the action of nucleoside analogs was proposed.
Insights
The tumor suppressor p53 protein
Area of Science:
- Molecular Biology
- Biochemistry
- Cancer Research
Background:
- The tumor suppressor p53 protein is crucial for cell-cycle regulation.
- The specific role of p53's 3'-to-5' exonuclease activity in DNA repair is not well understood.
Purpose of the Study:
- To investigate the 3'-to-5' exonuclease activity of p53 protein on nucleoside analogs.
- To determine if p53 can excise beta-L- and beta-D-nucleoside analogs with potential anticancer or antiviral properties.
Main Methods:
- In vitro exonuclease assay using defined oligonucleotides.
- Oligonucleotides were modified at the 3'-terminus with beta-D- and beta-L-nucleoside analogs.
Main Results:
- p53 protein demonstrated more efficient removal of beta-D-nucleoside analogs than beta-L-nucleoside analogs.
- p53 protein exhibited a 5-fold lower affinity for beta-L-nucleotide terminated primers compared to non-modified primers.
Conclusions:
- The 3'-to-5' exonuclease activity of p53 protein plays a role in the processing of nucleoside analogs.
- This suggests a potential mechanism for how p53 influences the efficacy of these therapeutic agents.