Biology Reference
In-Depth Information
Chapter 8
Many Pathways to Destruction: The Role
of the Centrosome in, and Its Control
by Regulated Proteolysis
Harold A. Fisk
Abstract Centrosome duplication must be precisely regulated to ensure the
production of a bipolar mitotic spindle. As with other cell cycle events, irreversible
protein destruction is critical for the fidelity of centrosome duplication, and the
failure to properly destroy any of several critical centrosome regulators leads to
the production of excess centrosomes that interfere with bipolar spindle assembly.
Many pathways that regulate the degradation of these critical regulators are found
at centrosomes, and in some cases the destruction occurs at the centrosome. This
chapter discusses the various degradation machineries found at centrosomes, and
some of the many aspects of centrosome biology that are controlled by protein
degradation.
8.1 Introduction
Regulated protein destruction is a key event in many cell cycle transitions, in part
because of its irreversibility. As well-known examples, the transition from meta-
phase to anaphase is controlled by the proteasome-dependent destruction of
securin, the molecule responsible for preventing premature activation of the cysteine
protease separase that destroys sister chromatid cohesion, and the exit from mitosis
is triggered by the proteasome-dependent destruction of cyclin B and other proteins.
When all goes well, regulated protein destruction contributes to a coordinated cell
cycle that culminates in the assembly of a bipolar mitotic spindle that partitions a
H. A. Fisk (
)
Department of Molecular Genetics, The Ohio State University,
484 West 12th Avenue, Columbus, OH 43210, USA
e-mail: fisk.13@osu.edu
&
 
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