A spoke in the wheel: Calcium spikes disrupt yeast cell cycle

A prerequisite of calcium signaling is the maintenance of cytoplasmic free Ca²⁺ within a narrow, sub-micromolar range, compatible with cell viability. A variety of stress inducing agents and drugs can lead to a disruption of calcium homeostasis with ensuing toxicity. Amiodarone, an anti-arrhythmic drug with broad range microbicidal effect, has been shown to trigger a calcium burst in the yeast Saccharomyces cerevisiae. Recently, we reported that amiodarone elicits a starvation response, blocks cell cycle progression at multiple stages and represses the transcription of cell cycle genes. Here, we examine the connections between Ca²⁺-calcineurin signaling, nutrient sensing and regulation of the cell cycle.