Related Experiment Video
Updated: Aug 2, 2026

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
Published on: March 9, 2012
Reconstitution of G1 cyclin ubiquitination with complexes containing SCFGrr1 and Rbx1
Abstract:
Control of cyclin levels is critical for proper cell cycle regulation. In yeast, the stability of the G1 cyclin Cln1 is controlled by phosphorylation-dependent ubiquitination. Here it is shown that this reaction can be reconstituted in vitro with an SCF E3 ubiquitin ligase complex. Phosphorylated Cln1 was ubiquitinated by SCF (Skp1-Cdc53-F-box protein) complexes containing the F-box protein Grr1, Rbx1, and the E2 Cdc34. Rbx1 promotes association of Cdc34 with Cdc53 and stimulates Cdc34 auto-ubiquitination in the context of Cdc53 or SCF complexes. Rbx1, which is also a component of the von Hippel-Lindau tumor suppressor complex, may define a previously unrecognized class of E3-associated proteins.
Related Concept Videos
Positive Regulator Molecules
Negative Regulator Molecules
Positive Regulator Molecules
Inhibition of Cdk Activity
Mitogens and the Cell Cycle
Anaphase Promoting Complex

