Figure 18-27. Two alternative models of how the kinetochore may generate a poleward force on its chromosome during anaphase A.

Figure 18-27Two alternative models of how the kinetochore may generate a poleward force on its chromosome during anaphase A

(A) Microtubule motor proteins at the kinetochore use the energy of ATP hydrolysis to pull the chromosome along its bound microtubules. Depolymerization of the kinetochore microtubules follows as a consequence. (B) Chromosome movement is driven by kinetochore microtubule disassembly: as tubulin subunits dissociate, the kinetochore is obliged to slide poleward to maintain its binding to the walls of the microtubule. As motor proteins are required for anaphase A, in this model, they would be required mainly for the microtubules to remain attached to the kinetochore.

From: Mitosis

Cover of Molecular Biology of the Cell
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
New York: Garland Science; 2002.
Copyright © 2002, Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter; Copyright © 1983, 1989, 1994, Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts, and James D. Watson .

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