Journal of Cell Science 116, e103-e103 (2003)
Copyright © 2003 The Company of Biologists Limited
Rethinking centriole duplication
Centrioles, like DNA, replicate exactly once every cell cycle. The daughter
centriole grows out at right angles from the existing centriole, ultimately
becoming an exact replica of its mother. The underlying mechanism probably
involves nucleated self-assembly, but how this generates a perfect copy, and
what regulates the process, remains a mystery. Patrick O'Farrell and
co-workers now implicate the mitotic kinase, CDK1, in control of centriole
replication (see p. 137). They
have used transmission electron microscopy (TEM) to examine centrioles in the
wing discs of Drosophila expressing a temperature-sensitive CDK1
mutant. At the nonpermissive temperature, three unusual centriole
configurations are apparent: (1) centriole triplets in which one mother is
associated with two daughters; (2) centriole triplets comprising a
grandmother, a mother and a daughter; and (3) centriole pairs in which the
daughter is longer than the mother. The authors' observations challenge the
prevailing notions that centrioles possess only one site for daughter assembly
and that mother and daughter must separate before a new centriole can be
synthesized. Moreover, they reveal that regulatory mechanisms, rather than
structure, can define features of centrioles such as their length and
number.
Related articles in JCS:
- Anomalous centriole configurations are detected in Drosophila wing disc cells upon Cdk1 inactivation
- Smruti J. Vidwans, Mei Lie Wong, and Patrick H. O'Farrell
JCS 2003 116: 137-143.
[Abstract]
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