A replicated chromosome possesses two discrete, complex, dynamic, macromolecular
assemblies, known as kinetochores, that are positioned on opposite sides of the primary�…

We argue that hypotheses for how chromosomes achieve a metaphase alignment, that are
based solely on a tug-of-war between poleward pulling forces produced along the length of�…

The somatic cells of all higher animals contain a single minute organelle called the
centrosome. For years, the functions of the centrosome were thought to revolve around its�…

During mitosis in Ptk1 cells anaphase is not initiated until, on average, 23+/-1 min after the
last monooriented chromosome acquires a bipolar attachment to the spindle--an event that�…

To test the popular but unproven assumption that the metaphase-anaphase transition in
vertebrate somatic cells is subject to a checkpoint that monitors chromosome (ie�…

During mitosis in cultured newt pneumocytes, one or more chromosomes may become
positioned well removed (greater than 50 microns) from the polar regions during early�…

In the presence of unattached/weakly attached kinetochores, the spindle assembly
checkpoint (SAC) delays exit from mitosis by preventing the anaphase-promoting complex�…

The proper segregation of sister chromatids in mitosis depends on bipolar attachment of all
chromosomes to the mitotic spindle. We have identified the small molecule Hesperadin as�…

Background: In cells lacking centrosomes, the microtubule-organizing activity of the
centrosome is substituted for by the combined action of chromatin and molecular motors�…

γ-Tubulin is a centrosomal component involved in microtubule nucleation. To determine how
this molecule behaves during the cell cycle, we have established several vertebrate somatic�…