title: Hierarchical organization of noise generates spontaneous signal in Paramecium cell.
abstract: In many cellular processes, spontaneous activities are often the basis for their functioning. Paramecium cells change their swimming direction under a homogeneous environment, which is induced by a spontaneous signal generation in the membrane electric potential. For such a spontaneous activity, a theoretical model has been proposed by Oosawa (2007) [Biosystems 88, 191-201.], in which intracellular noise is hierarchically organized from thermal fluctuations to spike-like large fluctuations, which induces a signal to change spontaneously the swimming direction. Our analysis of the model shows that the system is a kind of excitable media, in which a spike is induced by a stochastic fluctuation. We show conditions of channels properties to have a spike train.
authors.affiliation: Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Ooyama
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Shibata
mesh_terms: D000818:Animals; D004560:Electricity; D008564:Membrane Potentials / Q000502:physiology; D008954:Models, Biological; D010247:Paramecium / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D013269:Stochastic Processes; D013550:Swimming / Q000502:physiology