Related Experiment Video
Updated: Aug 10, 2026

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
Negative regulation of geminin by CDK-dependent ubiquitination controls replication licensing
1Wellcome Trust Biocentre, University of Dundee, Dundee, Scotland, UK.
Abstract:
The replication licensing system ensures the precise duplication of chromosomal DNA in each cell cycle. In metazoans, a small protein called geminin plays a central role in negatively regulating licensing late in the cell cycle. Recent work using Xenopus egg extracts shows how geminin activity is downregulated on exit from metaphase in a process that requires mitotic cyclin-dependent kinases (CDKs). Geminin is polyubiquitinated by the Anaphase Promoting Complex, but instead of being proteolysed-the normal fate of polyubiquitinated proteins-much of the geminin is deubiquitinated, leaving it inactive. These results suggest a simple model for how precise chromosome duplication is ensured in the Xenopus model system.
More Related Videos
Related Concept Videos
Negative Regulator Molecules
Inhibition of Cdk Activity
S-Cdk Initiates DNA Replication
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
DNA Damage Can Stall the Cell Cycle
Inhibition of CDK Activity
S-Cdk Initiates DNA Replication
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.

