Format

Send to

Choose Destination
Curr Biol. 2000 Nov 2;10(21):1367-70.

Centrosomes have a role in regulating the destruction of cyclin B in early Drosophila embryos.

Author information

1
Wellcome/CRC Institute and Department of Genetics, University of Cambridge, Cambridge, UK.

Abstract

We reported previously that the disappearance of cyclin B at the end of mitosis in early Drosophila embryos starts at centrosomes and spreads into the spindle [1]. Here, we used a novel mutation, centrosome fall off (cfo), to investigate whether centrosomes are required to initiate the disappearance of cyclin B from the spindle. In embryos laid by homozygous cfo mutant mothers, the centrosomes co-ordinately detached from the mitotic spindle during mitosis, and the centrosomeless spindles arrested at anaphase. Cyclin B levels decreased on the detached centrosomes, but not on the arrested centrosomeless spindles, presumably explaining why the spindles arrest in anaphase in these embryos. We found that the expression of a non-degradable cyclin B in embryos also caused an anaphase arrest, but most centrosomes remained attached to the arrested spindles, and non-degradable cyclin B levels remained high on both the centrosomes and spindles. These findings suggest that the disappearance of cyclin B from centrosomes and spindles is closely linked to its destruction, and that a connection between centrosomes and spindles is required for the proper destruction of the spindle-associated cyclin B in early Drosophila embryos. These results may have important implications for the mechanism of the spindle-assembly checkpoint, as they suggest that unattached kinetochores may arrest cells in mitosis, at least in part, by signalling to centrosomes to block the initiation of cyclin B destruction.

PMID:
11084336
DOI:
10.1016/s0960-9822(00)00776-4
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center