Related Experiment Video

Updated: Jul 17, 2025

Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis
08:33

Combining Mitotic Cell Synchronization and High Resolution Confocal Microscopy to Study the Role of Multifunctional Cell Cycle Proteins During Mitosis

Published on: December 5, 2017

14.3K

TOR complex 1 negatively regulates NDR kinase Cbk1 to control cell separation in budding yeast

Magdalena Foltman1,2, Iván Mendez2,3, Joan J Bech-Serra4

  • 1Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, Santander, Spain.

Plos Biology
|August 30, 2023
PubMed

Insights

Target of rapamycin complex 1 (TORC1) in yeast blocks cell separation after division. It achieves this by phosphorylating the Cbk1 protein kinase, impacting cell cycle progression and membrane fusion.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The target of rapamycin (TOR) pathway is crucial for coordinating cell growth and the cell cycle.
  • Mechanisms by which TOR regulates post-anaphase events, including cell separation, are not fully understood.

Purpose of the Study:

  • To elucidate the molecular mechanisms by which TOR signaling regulates cell separation in budding yeast.
  • To identify key proteins and phosphorylation events involved in TOR-mediated control of cytokinesis.

Main Methods:

  • Investigated the role of TOR complex 1 (TORC1) in budding yeast cell separation.
  • Utilized phosphomimetic substitution to analyze Cbk1 kinase activity.
  • Identified Sec3 as a substrate of Cbk1 and examined its interaction with SNARE components.

Main Results:

  • TORC1 was found to inhibit cell separation by phosphorylating the NDR kinase Cbk1.
  • Phosphorylation at residue T574 of Cbk1 was identified as critical for TORC1's control over cell separation.
  • TORC1 activity was shown to disrupt the interaction between Sec3 and t-SNARE, hindering membrane fusion.

Conclusions:

  • TORC1 negatively regulates cell separation in budding yeast through Cbk1 phosphorylation.
  • This pathway controls the fusion of secretory vesicles at the division site, impacting cytokinesis completion.

More Related Videos

Assay for Adhesion and Agar Invasion in S. cerevisiae04:36

Assay for Adhesion and Agar Invasion in S. cerevisiae

Published on: November 8, 2006

15.0K
Use of Time-Lapse Microscopy and Stage-Specific Nuclear Depletion of Proteins to Study Meiosis in S. cerevisiae07:48

Use of Time-Lapse Microscopy and Stage-Specific Nuclear Depletion of Proteins to Study Meiosis in S. cerevisiae

Published on: October 11, 2022

1.9K

Related Concept Videos

Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
4.8K
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.
35.4K
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,...
4.5K
Molecular Factors Affecting Cell Division01:27

Molecular Factors Affecting Cell Division

Several external and internal factors influence the initiation and inhibition of cell division. For instance, the death of nearby cells or the release of human growth hormone (hGH) promotes cell division. In contrast, lack of hGH or crowding of cells can inhibit cell division.
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...
3.2K
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...
3.0K
Positive Regulator Molecules02:39

Positive Regulator Molecules

Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
5.5K