propagation
Definition
Propagation in biological networks refers to the transmission and amplification of signals, perturbations, or effects through interconnected molecular pathways and cellular systems. This process describes how an initial stimulus (such as ligand binding, genetic mutation, or drug intervention) cascades through a network of interactions, affecting downstream components in a chain of causality. Propagation dynamics determine how biological information flows through protein-protein interactions, gene regulatory networks, and metabolic pathways. Understanding propagation is critical for predicting off-target drug effects, identifying disease mechanisms, and determining how local perturbations create system-wide phenotypic changes. The concept encompasses both direct transmission between connected nodes and indirect effects through multi-step pathways.
Visualize propagation in Nodes Bio
Researchers can visualize propagation patterns by mapping how perturbations spread through molecular interaction networks. Nodes Bio enables tracking signal flow from source nodes (receptors, mutated genes) through intermediate effectors to downstream targets. Users can identify critical propagation bottlenecks, measure path lengths, and analyze network topology to predict which nodes amplify or dampen signals, revealing therapeutic intervention points and potential biomarkers.
Visualization Ideas:
- Directed signal flow networks showing propagation from receptors through kinase cascades to transcription factors
- Heat map overlays on protein interaction networks displaying propagation intensity from perturbation source
- Time-series network animations showing temporal propagation dynamics through metabolic or regulatory pathways
Example Use Case
A cancer researcher investigating EGFR inhibitor resistance uses propagation analysis to understand how mutations bypass drug blockade. By mapping the EGFR signaling network, they visualize how signals propagate through alternative pathways when EGFR is inhibited. The analysis reveals that PI3K/AKT pathway activation propagates proliferation signals independently of EGFR, explaining resistance. This identifies PI3K as a combination therapy target, demonstrating how propagation analysis uncovers compensatory mechanisms that maintain pathological signaling despite targeted intervention.