Phosphate Starvation Alters Calcium Signaling in Roots of Arabidopsis Thaliana

The study investigated how phosphate (P) starvation affected calcium (Ca2+) signaling in the roots of Arabidopsis thaliana. It was found that P starvation, but not nitrogen starvation, significantly dampened the increase in cytosolic free Ca2+ ([Ca2+]cyt) in response to various stresses and extracellular nucleotides. This altered response was reversible with P resupply and was linked to high reactive oxygen species (ROS) levels in P-starved roots. The study concluded that P availability was not signaled through [Ca2+]cyt, and no aberrant root hair growth was observed in a library of 77 Ca2+ channel mutants under P starvation. These findings enhanced the understanding of how plants integrate nutritional and environmental signals, highlighting the complexity of Ca2+ as a signal transducer.