Initial source of heterogeneity in a model for cell fate decision in the early mammalian embryo.

During development, cells from a population of common progenitors evolve towards different fates characterized by distinct levels of specific transcription factors, a process known as cell differentiation. This evolution is governed by gene regulatory networks modulated by intercellular signalling. In order to evolve towards distinct fates, cells forming the population of common progenitors must display some heterogeneity.

Impact of β-Amyloids Induced Disruption of Ca Homeostasis in a Simple Model of Neuronal Activity.

Alzheimer's disease is characterized by a marked dysregulation of intracellular Ca homeostasis. In particular, toxic β-amyloids (Aβ) perturb the activities of numerous Ca transporters or channels. Because of the tight coupling between Ca dynamics and the membrane electrical activity, such perturbations are also expected to affect neuronal excitability.