Send to

Choose Destination
See comment in PubMed Commons below
Philos Trans R Soc Lond B Biol Sci. 2004 Jan 29;359(1441):99-108.

From a single double helix to paired double helices and back.

Author information

Research Institute for Molecular Biology (IMP), Dr. Bohr-Gasse 7, A-1030 Vienna, Austria.


The propagation of our genomes during cell proliferation depends on the movement of sister DNA molecules produced by DNA replication to opposite sides of the cell before it divides. This feat is achieved by microtubules in eukaryotic cells but it has long remained a mystery how cells ensure that sister DNAs attach to microtubules with opposite orientations, known as amphitelic attachment. It is currently thought that sister chromatid cohesion has a crucial role. By resisting the forces exerted by microtubules, sister chromatid cohesion gives rise to tension that is thought essential for stabilizing kinetochore-microtubule attachments. Efficient amphitelic attachment is therefore achieved by an error correction mechanism that selectively eliminates connections that do not give rise to tension. Cohesion between sister chromatids is mediated by a multisubunit complex called cohesin which forms a gigantic ring structure. It has been proposed that sister DNAs are held together owing to their becoming entrapped within a single cohesin ring. Cohesion between sister chromatids is destroyed at the metaphase to anaphase transition by proteolytic cleavage of cohesin's Scc1 subunit by a thiol protease called separase, which severs the ring and thereby releases sister DNAs.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center