The Language of Calcium Signaling

Ca 2+ signals are a core regulator of plant cell physiology and cellular responses to the environment. The channels, pumps, and carriers that underlie Ca 2+ homeostasis provide the mechanistic basis for generation of Ca 2+ signals by regulating movement of Ca 2+ ions between subcellular compartments and between the cell and its extracellular environment. The information encoded within the Ca 2+ transients is decoded and transmitted by a toolkit of Ca 2+ -binding proteins that regulate transcription via Ca 2+ -responsive promoter elements and that regulate protein phosphorylation. Ca 2+ -signaling networks have architectural structures comparable to scale-free networks and bow tie networks in computing, and these similarities help explain such properties of Ca 2+ -signaling networks as robustness, evolvability, and the ability to process multiple signals simultaneously.