title: Elimination of fast variables in chemical Langevin equations.
abstract: Internal and external fluctuations are ubiquitous in cellular signaling processes. Because biochemical reactions often evolve on disparate time scales, mathematical perturbation techniques can be invoked to reduce the complexity of stochastic models. Previous work in this area has focused on direct treatment of the master equation. However, eliminating fast variables in the chemical Langevin equation is also an important problem. We show how to solve this problem by utilizing a partial equilibrium assumption. Our technique is applied to a simple birth-death-dimerization process and a more involved gene regulation network, demonstrating great computational efficiency. Excellent agreement is found with results computed from exact stochastic simulations. We compare our approach with existing reduction schemes and discuss avenues for future improvement.
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill, North Carolina 27599-3290, USA.
authors.forename: Yueheng
authors.initials: Y
authors.lastname: Lan
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Elston
authors.forename: Garegin A
authors.initials: GA
authors.lastname: Papoian
mesh_terms: D000465:Algorithms; D019281:Dimerization; D053263:Gene Regulatory Networks; D008954:Models, Biological; D008956:Models, Chemical; D009068:Movement; D011336:Probability; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors; D015533:Transcriptional Activation
chemical_list: D011506:Proteins