...Michiel Boekhout; Rob Wolthuis Nek2 isoform A (Nek2A) is a presumed substrate of the anaphase‐promoting complex/cyclosome containing Cdc20 (APC/C Cdc20 ). Nek2A, like cyclin A, is degraded in mitosis while the spindle checkpoint is active. Cyclin A prevents spindle checkpoint proteins from binding...

...Nikki A. Copeland; Heather E. Sercombe; Rosemary H. C. Wilson; Dawn Coverley CIZ1 is a nuclear matrix protein that cooperates with cyclin A2 (encoded by CCNA2 ) and CDK2 to promote mammalian DNA replication. We show here that cyclin‐A–CDK2 also negatively regulates CIZ1 activity by phosphorylation...

... development. Previous studies have demonstrated a role for the DNA replication factors MCM5 and Orc1 in preventing centrosome reduplication. Cyclin A-Cdk2 localizes on centrosomes by means of a modular centrosomal localization sequence (CLS) that is distinct from that of cyclin E. Here, we show that cyclin...

... and with results from yeast and vertebrates, we show here that the effects of stabilized securin with mutations in the D-box are enhanced in vivo by reduced Polo kinase function or by mitotically stabilized Cyclin A. However, we also show that PIM contains a KEN-box, which is required for mitotic degradation...

... in the retina and lamina show delays in completion of the G2-M segment of the cell cycle. We have investigated the molecular basis of dally- mediated cell division defects by examining the genetic interactions between dally and known cell cycle regulators. Reductions in cyclin A but not cyclin B or string...

.... Affinity-depletion of cyclin dependent kinases (Cdks) from these extracts blocks the initiation of DNA replication. We define ‘S-phase promoting factor’ (SPF) as the Cdk activity required for DNA replication in these Cdk-depleted extracts. Recombinant cyclins A and E, but not cyclin B, showed significant...

...Franck Girard; Anne Fernandez; Ned Lamb ABSTRACT Cyclins A and B are known to exhibit significant differences in their function, cellular distribution and timing of degradation at mitosis. On the basis of observations in marine invertebrates and Xenopus , it was proposed that cyclin destruction...