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Updated: Jan 27, 2026
14:27
A Cell-Free Assay Using Xenopus laevis Embryo Extracts to Study Mechanisms of Nuclear Size Regulation
Published on: August 8, 2016
8.8K
Controlling organism size by regulating constituent cell numbers.
Saurabh Modi1, Abhyudai Singh2
1Department of Biomedical Engineering, University of Delaware, Newark, DE USA 19716. saurmodi@udel.edu.
Proceedings of the ... IEEE Conference on Decision & Control. IEEE Conference on Decision & Control
|March 20, 2019
Summary
Cells use secreted factors for density-dependent proliferation control. Optimal feedback strength balances noise reduction, with short-lived factors offering better buffering against fluctuations in cell numbers.
Area of Science:
- Cellular Biology
- Developmental Biology
- Systems Biology
Background:
- Cell counting mechanisms are crucial for regulating organism and tissue size.
- Cells often use secreted extracellular factors for negative feedback on proliferation.
- Minimizing factor production is desirable for energy efficiency and predator avoidance.
Purpose of the Study:
- To formulate a stochastic model of cell proliferation with feedback control.
- To investigate the impact of feedback strength on cell number fluctuations.
- To analyze the effects of external disturbances on feedback mechanisms.
Main Methods:
- Stochastic modeling of cell proliferation.
- Analysis of feedback control via secreted extracellular factors.
- Simulation of external disturbances in proliferation and factor synthesis rates.
Main Results:
- Low feedback levels minimize cell number fluctuations; high levels amplify them.
- An optimal feedback strength exists, limiting noise suppression.
- Short-lived factors provide more efficient noise buffering.
- Negative feedback mitigates proliferation rate disturbances but amplifies synthesis rate disturbances.
Conclusions:
- Cellular feedback mechanisms exhibit an optimal strength for noise suppression.
- Factor lifespan influences the efficiency of noise buffering.
- Feedback control has differential effects on disturbances in proliferation versus synthesis rates.
- These findings apply across diverse organisms, from microbes to human cells.
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