c12_dyn_mod_conc_handout - The two faces of network...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 The two faces of network dynamics Evolving network models describe the dynamics/assembly/evolution of networks by the addition/removal of nodes and edges. It is possible to have network dynamics even if there are no node/edge additions/removals, i.e. the network is fixed. This can be called dynamics on the network. In many networks node attributes can change in time or depending on context. E.g. the abundance of chemicals in a chemical reaction network the health status of individuals in a disease contact network For these networks it is not enough to specify the nodes and edges, we also need to define a node state ( e.g. a continuous variable, or a discrete category). Each node’s state is determined by the states of the nodes adjacent to it (in directed networks the orientation of the edges should be toward the regulated node). Understanding the dynamics and function of molecular/cellular networks Cells are complex systems functionally diverse elements these elements’ abundances and activities change in time or based on context diverse interactions that form networks signal transduction-, gene regulatory-, metabolic- have a function that needs to be performed sense and respond to the environment maintain homeostasis need certain dynamical features sensitive to some changes, insensitive/adaptable to others robust to unwanted perturbations What is the relationship between the topological features of intracellular interaction networks and the dynamic behavior of cells? Toward network dynamics Network topology needs to be complemented by a description of network dynamics – states of the nodes and changes in the state First step - pseudo-dynamics : propagation of activation in interaction space, starting from a source (signal) This can only be done in directed networks. In effect we use topological analysis as a proxy for dynamic information on signal propagation. Q: What topological properties should be studied and what dynamic properties do they reflect? Pseudodynamic signal propagation Act., dist. 2 Act., dist. 4 Inh., dist 2
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Pseudodynamic effects of knockouts Forward and reverse dynamic modeling Dynamic modeling of interaction network: Input: components; interactions; states of components Hypotheses: interaction network; transfer functions; parameters Output: behavior of components in time Validation: capture known behavior
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 6

c12_dyn_mod_conc_handout - The two faces of network...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online