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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
PubMed

Insights

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.
Keywords:
G1 arrestLINuScell cyclecell cycle inhibitor p21/CDKN1Acryptochrome 2optogenetics

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