Related Experiment Video
Updated: Jul 15, 2025
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
60.5K
Cell Cycle Control by Optogenetically Regulated Cell Cycle Inhibitor Protein p21
Levin Lataster1, Hanna Mereth Huber1, Christina Böttcher1
1Faculty of Biology, Institute of Biology II, University of Freiburg, 79098 Freiburg, Germany.
Biology
|September 28, 2023
Summary
Researchers developed a light-controlled system to arrest cells in the G1 phase, enhancing productivity. This optogenetic approach precisely manipulates cell cycle inhibitor p21/CDKN1A localization for optimized bioprotein production.
Area of Science:
- Cell biology
- Optogenetics
- Biotechnology
Background:
- Cell cycle progression is regulated by cyclin-dependent kinases and cyclins.
- The cell cycle inhibitor p21/CDKN1A arrests cells in the G1 phase, promoting cell growth and productivity.
- Controlling subcellular localization of proteins offers a way to modulate cellular functions.
Purpose of the Study:
- To develop an optogenetic system for controlling the subcellular localization and nuclear function of p21/CDKN1A.
- To investigate the effect of light-controlled p21/CDKN1A on cell cycle arrest and productivity.
- To optimize biotherapeutic protein production by uncoupling proliferation and cell cycle arrest.
Main Methods:
- Fusion of p21/CDKN1A with blue light-sensitive proteins (cryptochrome 2/CIBN and LINuS).
- Application of blue LED light to control p21 localization and nuclear function.
- Measurement of cell cycle arrest in G1 phase and reporter protein (secreted alkaline phosphatase) productivity.
Main Results:
- Both p21-CRY2/CIB1 and p21-LINuS systems successfully induced G1 phase arrest in cells upon blue light exposure.
- Light-controlled p21/CDKN1A increased cell-specific productivity of the reporter protein.
- The degree of cell cycle arrest and productivity could be fine-tuned by adjusting light exposure intervals and dose.
Conclusions:
- Optogenetic control of p21/CDKN1A localization is feasible and effectively induces G1 arrest.
- This approach allows for precise temporal control over cell cycle progression and cellular productivity.
- Light-controllable p21/CDKN1A holds potential for optimizing the production of biotherapeutic proteins in producer cell lines.
More Related Videos
09:32Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development
Published on: June 15, 2017
8.8K
12:02Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
27.4K
Related Concept Videos
02:34Inhibition of Cdk Activity
4.8K
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
01:23Negative Regulator Molecules
35.4K
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
01:28The Cell Cycle Control System
3.0K
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...
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and...
3.0K
01:27Molecular Factors Affecting Cell Division
3.2K
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...
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
02:39Positive Regulator Molecules
5.5K
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
02:37DNA Damage can Stall the Cell Cycle
9.2K
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
9.2K