Related Experiment Video

Updated: Aug 24, 2026

Visualizing the DNA Damage Response in Purkinje Cells Using Cerebellar Organotypic Cultures
08:41

Visualizing the DNA Damage Response in Purkinje Cells Using Cerebellar Organotypic Cultures

Published on: December 27, 2024

Poly(ADP-ribose) polymerase-1 inhibits ATM kinase activity in DNA damage response

Fumiaki Watanabe1, Hidesuke Fukazawa, Mitsuko Masutani

  • 1Department of Bioactive Molecules, National Institute of Infectious Disease, 1-23-1 Toyama, Shinjyuku-ku, Tokyo 162-8640, Japan.

Biochemical and Biophysical Research Communications
|June 5, 2004
PubMed

Insights

Poly(ADP-ribose) polymerase-1 (PARP-1) inhibits ataxia-telangiectasia mutated (ATM) kinase activity following DNA double-strand breaks (DSB). PARP-1 deficiency enhances ATM activation, suggesting PARP-1 negatively regulates ATM in DNA repair.

Area of Science:

  • Molecular Biology
  • DNA Repair Mechanisms
  • Cellular Signaling

Background:

  • DNA double-strand breaks (DSB) are critical DNA lesions that trigger cellular responses.
  • The ataxia-telangiectasia mutated (ATM) kinase is a key regulator of DNA repair and cell cycle checkpoints following DSB.
  • Poly(ADP-ribose) polymerase-1 (PARP-1) is involved in DNA repair pathways.

Purpose of the Study:

  • To investigate the regulatory relationship between PARP-1 and ATM kinase activity in response to DSB.
  • To determine if PARP-1 influences ATM-mediated signaling pathways.

Main Methods:

  • Biochemical fractionation to assess protein localization at chromatin.
  • Induction of DSB using neocarzinostatin (NCS) in wild-type and Parp-1 knockout mouse embryonic fibroblasts (MEF) and embryonic stem (ES) cells.
  • Western blotting to detect phosphorylation of histone H2AX and p53.
  • In vitro kinase assays to assess ATM activity in the presence of PARP-1.

Main Results:

  • PARP-1 and ATM accumulate at chromatin following NCS-induced DSB.
  • NCS treatment induced significantly higher phosphorylation of histone H2AX and p53 in Parp-1 knockout MEF and ES cells compared to wild-type.
  • In vitro, PARP-1 inhibited ATM-mediated phosphorylation of p53 and (32)P-incorporation in a DNA-dependent manner.

Conclusions:

  • PARP-1 negatively regulates ATM kinase activity in response to DNA double-strand breaks.
  • The absence of PARP-1 leads to enhanced ATM activation and downstream signaling.
  • These findings reveal a novel inhibitory role for PARP-1 in the DNA damage response pathway mediated by ATM.

More Related Videos

Detection and Visualization of DNA Damage-induced Protein Complexes in Suspension Cell Cultures Using the Proximity Ligation Assay13:10

Detection and Visualization of DNA Damage-induced Protein Complexes in Suspension Cell Cultures Using the Proximity Ligation Assay

Published on: June 9, 2017

Laser Microirradiation to Study In Vivo Cellular Responses to Simple and Complex DNA Damage10:44

Laser Microirradiation to Study In Vivo Cellular Responses to Simple and Complex DNA Damage

Published on: January 31, 2018

Related Concept Videos

DNA Damage can Stall the Cell Cycle02:36

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
DNA Damage Can Stall the Cell Cycle02:36

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
Restarting Stalled Replication Forks02:37

Restarting Stalled Replication Forks

DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
Allosteric Proteins-ATCase01:19

Allosteric Proteins-ATCase

Binding sites linkages can regulate a protein's function.  For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to  N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
Translesion DNA Polymerases02:10

Translesion DNA Polymerases

Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.