title: Stochastic noise interferes coherently with a model biological clock and produces specific dynamic behaviour.
abstract: The influence of noise is unavoidable in all living systems. Its impact on a model of a biological clock, normally running in regular oscillating modes, is examined. It is shown that in a specific system in which endogenous rhythmicity is produced by a beat oscillator acting on a feedback coupled metabolic pool system, noise can act coherently to produce unexpected dynamic behaviour, running from regular over pseudo-regular to irregular time-structures. If the biological system consists of a set of identical weakly coupled cells, stochasticity may lead to phase decoupling producing irregular spatio-temporal patterns. Synchronization via phase resetting can be achieved by external short-time temperature pulses. Explicit results are obtained for the well-studied circadian photosynthesis oscillations in plants performing crassulacean acid metabolism. Because of the generic structure of the underlying nonlinear dynamics they can, however, be regarded as a general property of the influence of noise on nonlinear excitable systems with fixed points occuring close to limit cycles.
authors: Institute of Nuclear Physics, Department of Physics, Darmstadt University of Technology, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany.
authors: F
authors: F
authors: Beck
authors: B
authors: B
authors: Blasius
authors: U
authors: U
authors: Lüttge
authors: R
authors: R
authors: Neff
authors: U
authors: U
authors: Rascher
mesh_terms: D001683:Biological Clocks; D002940:Circadian Rhythm; D019684:Magnoliopsida / Q000378:metabolism; D008954:Models, Biological; D017711:Nonlinear Dynamics; D010788:Photosynthesis; D013269:Stochastic Processes