Premium
The disappearance of cyclin B at the end of mitosis is regulated spatially in Drosophila cells
Author(s) -
Huang Junyong,
Raff Jordan W.
Publication year - 1999
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1093/emboj/18.8.2184
Subject(s) - biology , mitosis , microbiology and biotechnology , drosophila (subgenus) , cyclin , cyclin b , cyclin a , cyclin a2 , cell cycle , genetics , gene
We have followed the behaviour of a cyclin B–green fluorescent protein (GFP) fusion protein in living Drosophila embryos in order to study how the localization and destruction of cyclin B is regulated in space and time. We show that the fusion protein accumulates at centrosomes in interphase, in the nucleus in prophase, on the mitotic spindle in prometaphase and on the microtubules that overlap in the middle of the spindle in metaphase. In cellularized embryos, toward the end of metaphase, the spindle‐associated cyclin B–GFP disappears from the spindle in a wave that starts at the spindle poles and spreads to the spindle equator; when the cyclin B–GFP on the spindle is almost undetectable, the chromosomes enter anaphase, and any remaining cytoplasmic cyclin B–GFP then disappears over the next few minutes. The endogenous cyclin B protein appears to behave in a similar manner. These findings suggest that the inactivation of cyclin B is regulated spatially in Drosophila cells. We show that the anaphase‐promoting complex/cyclosome (APC/C) specifically interacts with microtubules in embryo extracts, but it is not confined to the spindle in mitosis, suggesting that the spatially regulated disappearance of cyclin B may reflect the spatially regulated activation of the APC/C.