Related Experiment Video

Updated: Dec 10, 2025

Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis
08:33

Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis

Published on: December 5, 2017

14.7K

ATR Restrains DNA Synthesis and Mitotic Catastrophe in Response to CDC7 Inhibition

Michael D Rainey1, Declan Bennett2, Rachel O'Dea1

  • 1Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Galway H91W2TY, Ireland.

Cell Reports
|September 3, 2020
PubMed

Insights

Loss of ETAA1 or RIF1 enhances cell proliferation during CDC7 inhibition by improving DNA replication. Inhibiting ATR after CDC7 inhibition unleashes origin firing, leading to defective mitosis.

Area of Science:

  • Cell biology
  • Molecular biology
  • Genetics

Background:

  • DNA replication relies on origin firing, regulated by CDC7 kinase.
  • CDC7 inhibitors (CDC7is) limit cell proliferation by impeding origin firing.

Purpose of the Study:

  • Identify genes that, upon loss, confer resistance to CDC7is.
  • Elucidate the role of ATR in mediating CDC7 inhibition effects.

Main Methods:

  • CRISPR-Cas9 genome-wide screen
  • Cell proliferation assays
  • Western blotting
  • Immunofluorescence microscopy

Main Results:

  • Loss of ETAA1 (ATR activator) and RIF1 reduces sensitivity to CDC7is, enhancing DNA synthesis during late S phase.
  • Partial CDC7 inhibition induces ATR via ETAA1.
  • Subsequent ATR inhibition unleashes origin firing in a CDK- and CDC7-dependent manner.
  • ETAA1 and TOPBP1 co-depletion recapitulates the premature, defective mitosis phenotype.

Conclusions:

  • ETAA1 is a key mediator of ATR activation downstream of CDC7 inhibition.
  • ATR inhibition overrides CDC7 inhibition's effects on origin firing.
  • This study provides a framework for understanding the origin firing checkpoint.
Keywords:
CRISPR-Cas9 screenDNA replicationETAA1RIF1cell cyclecheckpointfunctional genomicskinase inhibitorreplication originsreplication stress

More Related Videos

Visualization of Replisome Encounters with an Antigen Tagged Blocking Lesion08:24

Visualization of Replisome Encounters with an Antigen Tagged Blocking Lesion

Published on: July 27, 2021

1.6K
Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast08:13

Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast

Published on: September 26, 2025

334

Related Concept Videos

DNA Damage can Stall the Cell Cycle02:37

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...
9.8K
DNA Damage Can Stall the Cell Cycle02:37

DNA Damage Can Stall the Cell Cycle

2.9K
Separation of Sister Chromatids02:17

Separation of Sister Chromatids

At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
4.2K
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
5.4K
Anaphase Promoting Complex00:50

Anaphase Promoting Complex

The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
3.2K
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.
37.8K