A preference for link operator functions can drive Boolean biological networks towards critical dynamics
Ajay Subbaroyan1, Olivier C Martin, Areejit Samal
1The Institute of Mathematical Sciences (IMSc), Chennai 600113, India.
Journal of Biosciences
|March 23, 2022
Summary
Link operator functions (LOFs) are a small subset of Boolean functions (BFs) crucial for biological network dynamics. This study shows LOFs drive biological networks toward criticality, offering a new modeling approach.
Area of Science:
- Systems Biology
- Computational Biology
- Network Science
Background:
- Boolean functions (BFs) model regulatory logic in biological networks.
- Effective and unate functions (EUFs) represent biologically relevant BFs.
- Link operator functions (LOFs) are a specific, understudied type of BF.
Purpose of the Study:
- To theoretically characterize Link Operator Functions (LOFs) within the broader context of Boolean functions (BFs).
- To investigate the prevalence and significance of LOFs in reconstructed biological networks.
- To demonstrate how LOFs can refine Boolean models of biological networks using steady-state constraints.
Main Methods:
- Theoretical enumeration and classification of LOFs.
- Analysis of LOF abundance in existing biological Boolean network reconstructions.
- Application of steady-state constraints to BFs to identify LOF-driven models.
Main Results:
- LOFs constitute a minuscule subset of all BFs and biologically relevant EUFs.
- AND-NOT LOFs are disproportionately frequent in reconstructed biological networks.
- Steady-state constraints significantly reduce the space of viable Boolean models by favoring LOFs.
- LOFs demonstrably steer biological network dynamics towards criticality.
Conclusions:
- LOFs represent a specialized class of Boolean functions with significant implications for biological network modeling.
- The abundance of LOFs in biological networks suggests their functional importance.
- Utilizing LOFs and steady-state constraints offers a powerful method for simplifying and analyzing complex biological systems.
- LOFs are key drivers of critical dynamics in biological networks, providing insights into network robustness and adaptability.
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