Speaker
Description
A response curve measures the output of a biological system at equilibrium against an input parameter $u$, which could be a rate constant, or amount of a stimulus (poison, drug, ligand, etc.). Of interest is the shape of a response curve: does it have a plateau region (homeostasis); is it monotonic? In T-cell's response to antigen, a non-monotonic (i.e., biphasic) response has been observed. For systems where $u$ directly affects one variable, we previously proved that either an incoherent feedforward loop, or a combination of positive and negative feedback loops, is necessary for biphasic response. In this talk, we consider the case where $u$ impacts multiple variables, for example if $u$ is the rate constant of a reaction. Finally, we comment more generally on translating motifs between the influence diagram and the reaction network.
