ATR mediates a checkpoint at the nuclear envelope in response to mechanical stress

Cell. 2014 Jul 31;158(3):633-46. doi: 10.1016/j.cell.2014.05.046.


ATR controls chromosome integrity and chromatin dynamics. We have previously shown that yeast Mec1/ATR promotes chromatin detachment from the nuclear envelope to counteract aberrant topological transitions during DNA replication. Here, we provide evidence that ATR activity at the nuclear envelope responds to mechanical stress. Human ATR associates with the nuclear envelope during S phase and prophase, and both osmotic stress and mechanical stretching relocalize ATR to nuclear membranes throughout the cell cycle. The ATR-mediated mechanical response occurs within the range of physiological forces, is reversible, and is independent of DNA damage signaling. ATR-defective cells exhibit aberrant chromatin condensation and nuclear envelope breakdown. We propose that mechanical forces derived from chromosome dynamics and torsional stress on nuclear membranes activate ATR to modulate nuclear envelope plasticity and chromatin association to the nuclear envelope, thus enabling cells to cope with the mechanical strain imposed by these molecular processes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ataxia Telangiectasia Mutated Proteins / metabolism
  • Cell Cycle Checkpoints
  • Cell Line, Tumor
  • Checkpoint Kinase 1
  • Chromatin / metabolism
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • HeLa Cells
  • Humans
  • Mice
  • NIH 3T3 Cells
  • Nuclear Envelope / metabolism*
  • Osmosis
  • Protein Kinases / metabolism
  • Stress, Mechanical*


  • Chromatin
  • Protein Kinases
  • Atr protein, mouse
  • ATR protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • Checkpoint Kinase 1