Related Experiment Video

Updated: Sep 21, 2026

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations
10:54

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations

Published on: September 17, 2012

The role of proteolysis in cell cycle progression in Schizosaccharomyces pombe

H Yamano1, J Gannon, T Hunt

  • 1ICRF Clare Hall Laboratories, South Mimms, Herts, UK.

The EMBO Journal
|October 1, 1996
PubMed

Insights

The destruction of Cdc13 (a B-type cyclin) is essential for mitotic exit in Schizosaccharomyces pombe. Its destruction box, RHALDDVSN, is key for this process and for regulating cell cycle progression.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • B-type cyclins are crucial regulators of the cell cycle.
  • Proteolysis of cyclins, particularly via the destruction box motif, controls cell cycle transitions.
  • Understanding cyclin degradation is key to understanding cell cycle control.

Purpose of the Study:

  • To identify the destruction box of the Schizosaccharomyces pombe B-type cyclin, Cdc13.
  • To investigate the role of Cdc13 destruction in mitotic exit and cell cycle progression.
  • To explore the proteolytic machinery involved in cyclin degradation.

Main Methods:

  • Utilized a cell-free system derived from Xenopus eggs.
  • Expressed modified Cdc13 proteins in Schizosaccharomyces pombe.
  • Analyzed the effects of indestructible Cdc13 and N-terminal fragments on cell cycle progression.

Main Results:

  • Identified residues 59-67 (RHALDDVSN) as the destruction box of Cdc13.
  • Indestructible Cdc13 blocked cells in anaphase and inhibited septation, indicating its destruction is necessary for mitotic exit.
  • A competitive inhibitor of destruction box-mediated proteolysis inhibited both sister chromatid separation and Cdc13 destruction.
  • Expression of a Cdc13 fragment overcame G1 arrest in cdc10 mutants, suggesting shared proteolytic machinery.

Conclusions:

  • Cdc13 destruction is a critical requirement for exit from mitosis in S. pombe.
  • The identified destruction box is essential for regulating Cdc13 proteolysis and cell cycle progression.
  • The same proteolytic machinery degrades Cdc13 and proteins required for S phase initiation.

More Related Videos

Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast11:19

Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast

Published on: February 20, 2017

Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast08:13

Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast

Published on: September 26, 2025

Related Concept Videos

Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
The Cell Cycle Control System02:11

The Cell Cycle Control System

The cell cycle is an organized set of events that leads the cell to divide into two daughter cells, each containing chromosomes identical to the parent cell. It is the cell cycle that leads to the formation of an entire organism from a single-cell zygote. Besides, cell division also functions in the renewal or repair of tissues in adult multicellular eukaryotes. For example, in the bone marrow, the stem cells divide to form new blood cells. Although essential for several functions, cell...
Cells Coordinate Growth and Proliferation02:36

Cells Coordinate Growth and Proliferation

Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
Separation of Sister Chromatids02:17

Separation of Sister Chromatids

At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
Anaphase Promoting Complex00:50

Anaphase Promoting Complex

The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
The Cell Cycle Control System01:28

The Cell Cycle Control System

The cell cycle regulation directs how a cell proceeds from one phase to the next and begins mitosis. The cell cycle control system includes intracellular regulatory molecules and external triggers. They provide "stop" or "advance" signals and operate at specific cell cycle stages termed checkpoints to ensure that a particular process is completed before the cell advances to the next phase.
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...