• Register
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.


Leaving Community

Are you sure you want to leave this community? Leaving the community will revoke any permissions you have been granted in this community.


Human Asf1 regulates the flow of S phase histones during replicational stress.

Maintenance of chromosomal integrity requires tight coordination of histone biosynthesis with DNA replication. Here, we show that extracts from human cells exposed to replication stress display an increased capacity to support replication-coupled chromatin assembly. While in unperturbed S phase, hAsf1 existed in equilibrium between an active form and an inactive histone-free pool, replication stress mobilized the majority of hAsf1 into an active multichaperone complex together with histones. This active multichaperone complex was limiting for chromatin assembly in S phase extracts, and hAsf1 was required for the enhanced assembly activity in cells exposed to replication stress. Consistently, siRNA-mediated knockdown of hAsf1 impaired the kinetics of S phase progression. Together, these data suggest that hAsf1 provides the cells with a buffering system for histone excess generated in response to stalled replication and explains how mammalian cells maintain a critical "active" histone pool available for deposition during recovery from replication stresses.

Pubmed ID: 15664198


  • Groth A
  • Ray-Gallet D
  • Quivy JP
  • Lukas J
  • Bartek J
  • Almouzni G


Molecular cell

Publication Data

January 21, 2005

Associated Grants


Mesh Terms

  • Animals
  • Cell Cycle Proteins
  • Cell Fractionation
  • Cell Line, Tumor
  • Chromatin
  • DNA Replication
  • Histones
  • Humans
  • Hydroxyurea
  • Macromolecular Substances
  • Molecular Chaperones
  • Nucleic Acid Synthesis Inhibitors
  • S Phase