Separating sister chromatids.
Loss of cohesion between sister chromatids triggers their segregation during anaphase. Recent work has identified both a cohesin complex that holds sisters together and a sister-separating protein, separin, that destroys cohesion. Separins are bound by inhibitory proteins whose proteolysis at the metaphase-anaphase transition is mediated by the anaphase-promoting complex and its activator protein CDC20 (APCCDC20). When chromosomes are misaligned, a surveillance mechanism (checkpoint) blocks sister separation by inhibiting APCCDC20. Defects in this apparatus are implicated in causing aneuploidy in human cells.
Nasmyth
K
K
IMP Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, A-1030 Vienna, Austria. Nasmyth@nt.imp.univie.ac.at
D000705:Anaphase; D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D018797:Cell Cycle Proteins / Q000502:physiology; D002842:Chromatids / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008025:Ligases / Q000502:physiology; D008540:Meiosis; D008677:Metaphase; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases
D018797:Cell Cycle Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases