The sister bonding of duplicated chromosomes

Hui Zou1

  • 1Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX 75252-9148, United States. hui.zou@utsouthwestern.edu

Abstract

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As cells progress into mitosis, the nuclear envelope breaks down, and the condensed chromosomes are exposed to the array of bipolar microtubules of the mitotic spindle. The kinetochore, a large, disc-shaped protein complex, is present at the centromere region of the sister chromatids and acts as a binding site for the microtubules.  Usually, the plus-end of a single microtubule is embedded within the kinetochore. However, some kinetochores first establish lateral contact with the side-wall of a...