Journal of Cell Science 115, e1404-e1404 (2002)
© 2002 The Company of Biologists Limited
Compartmentalization of anaphase-promoting complexes
The anaphase-promoting complex (APC) promotes the ubiquitylation and
destruction of cyclin B and other proteins during mitosis. It targets
different substrates at different times, and degradation of a substrate can
depend on its subcellular location. In syncytial Drosophila embryos,
for example, only spindle-associated cyclin B is degraded. How this is
achieved is far from clear — particularly given controversy over where
APC itself resides. Jun-yong Huang and Jordan Raff have approached the problem
by expressing GFP fusion proteins containing core APC subunits (Cdc27 and
Cdc16) in syncytial fly embryos (see p.
2847). They find that, at mitosis, only a small fraction of cellular
APC associates with the spindle. Global activation of spindle-restricted APC
therefore cannot be responsible for cyclin B degradation; instead the cell
must specifically activate an APC subpopulation. Huang and Raff also find that
GFP-Cdc27 associates with mitotic chromosomes but GFP-Cdc16 does not;
moreover, they show that RNAi-induced depletion of Cdc27 and Cdc16 produces
distinct mitotic-arrest phenotypes. This suggests that cells produce multiple
forms of APC, which are differentially localized and have distinct
functions.
Related articles in JCS:
- The dynamic localisation of the Drosophila APC/C: evidence for the existence of multiple complexes that perform distinct functions and are differentially localised
- Jun-yong Huang and Jordan W. Raff
JCS 2002 115: 2847-2856.
[Abstract]
[Full Text]
