Osmosensing and osmoregulation in unicellular eukaryotes.

Eukaryotic microorganisms possess mechanisms to detect osmotic variations in their surroundings, from specialized receptors and membrane transporters, to sophisticated systems such as two-component histidine kinases. Osmotic stimuli are transduced through conserved phosphorylation cascades that result in a rapid response to mitigate stress. This response allows for the maintenance of an optimal biochemical environment for cell functioning, as well as a suitable recovery in suboptimal environments that would otherwise endanger cell survival.