title: A network characteristic that correlates environmental and genetic robustness.
abstract: As scientific advances in perturbing biological systems and technological advances in data acquisition allow the large-scale quantitative analysis of biological function, the robustness of organisms to both transient environmental stresses and inter-generational genetic changes is a fundamental impediment to the identifiability of mathematical models of these functions. An approach to overcoming this impediment is to reduce the space of possible models to take into account both types of robustness. However, the relationship between the two is still controversial. This work uncovers a network characteristic, transient responsiveness, for a specific function that correlates environmental imperturbability and genetic robustness. We test this characteristic extensively for dynamic networks of ordinary differential equations ranging up to 30 interacting nodes and find that there is a power-law relating environmental imperturbability and genetic robustness that tends to linearity as the number of nodes increases. Using our methods, we refine the classification of known 3-node motifs in terms of their environmental and genetic robustness. We demonstrate our approach by applying it to the chemotaxis signaling network. In particular, we investigate plausible models for the role of CheV protein in biochemical adaptation via a phosphorylation pathway, testing modifications that could improve the robustness of the system to environmental and/or genetic perturbation.
authors.affiliation: Laboratory of Biological Modeling, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Zeina
authors.initials: Z
authors.lastname: Shreif
authors.affiliation: Laboratory of Biological Modeling, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Vipul
authors.initials: V
authors.lastname: Periwal
mesh_terms: D001426:Bacterial Proteins / Q000502:physiology; D002630:Chemotactic Factors / Q000502:physiology; D002633:Chemotaxis; D019295:Computational Biology; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology; D029968:Escherichia coli Proteins / Q000502:physiology; D059647:Gene-Environment Interaction; D055641:Mathematical Concepts; D008954:Models, Biological; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D002630:Chemotactic Factors; D029968:Escherichia coli Proteins; C087011:cheV protein, bacteria