Trading bits in the readout from a genetic network.
Marianne Bauer1,2,3,4, Mariela D Petkova5, Thomas Gregor6,2,7
1Joseph Henry Laboratories of Physics, Princeton University, Princeton, NJ 08544; mb67@princeton.edu wbialek@princeton.edu.
Summary
Cells precisely measure transcription factor concentrations for gene regulation, facing physical limits. Lower thresholds in measurements are key for optimal information transmission, as seen in fly embryos.
Area of Science:
- Developmental Biology
- Systems Biology
- Genetics
Background:
- Gene expression regulation relies on cells measuring transcription factor concentrations.
- Physical limitations constrain the precision of these molecular measurements.
- The gap gene network in early fly embryos provides a model system for studying this measurement problem.
Purpose of the Study:
- To investigate the tradeoff between measurement precision and information transmission in gene regulation.
- To determine optimal sensing strategies under physical constraints.
- To explain the necessity of complex enhancer elements in gene regulation.
Main Methods:
- Analysis of information transmission in biological sensing mechanisms.
- Application of information theory to model cellular measurements.
- Examination of the gap gene network in Drosophila melanogaster.
Main Results:
- Lower measurement thresholds are crucial for efficient information transfer.
- Fine-tuning of sensors is not essential for near-optimal information transmission.
- Thresholded sensors can achieve near information-theoretic optima.
Conclusions:
- Physical limitations in sensing necessitate complex enhancer elements responding to factor combinations.
- Optimal sensing strategies can be identified using an information-theoretic approach.
- Understanding these principles provides insight into the evolution of gene regulatory networks.
