Interlinked fast and slow positive feedback loops drive reliable cell decisions.
Positive feedback is a ubiquitous signal transduction motif that allows systems to convert graded inputs into decisive, all-or-none outputs. Here we investigate why the positive feedback switches that regulate polarization of budding yeast, calcium signaling, Xenopus oocyte maturation, and various other processes use multiple interlinked loops rather than single positive feedback loops. Mathematical simulations revealed that linking fast and slow positive feedback loops creates a "dual-time" switch that is both rapidly inducible and resistant to noise in the upstream signaling system.
Brandman
Onn
O
Department of Molecular Pharmacology, Stanford University School of Medicine, Stanford, CA, 94305, USA. onn@stanford.edu
Ferrell
James E
JE
Li
Rong
R
Meyer
Tobias
T
D000818:Animals; D020013:Calcium Signaling; D002468:Cell Physiological Phenomena; D003198:Computer Simulation; D025461:Feedback, Physiological; D008433:Mathematics; D008954:Models, Biological; D009865:Oocytes / Q000502:physiology; D010641:Phenotype; D004718:Saccharomycetales / Q000166:cytology / Q000502:physiology; D015398:Signal Transduction; D049490:Systems Biology; D014981:Xenopus