Extracellular ATP: An Essential Apoplastic Messenger in Plants
Adenosine triphosphate (ATP) plays major roles in cell metabolism as an energy supplier and as a substrate for enzymatic reactions. While ATP is well known for its role as an intracellular energy carrier, recent studies have found that ATP exists not only in the cytoplasm, but also in the extracellular matrix. Cytoplasmic ATP can be secreted into the apoplast through wound leakage, secretory vesicles, or transporters in the plasma membrane. As a signaling molecule, extracellular ATP (eATP) regulates plant metabolism, growth and development, and responses to biotic and abiotic stimuli. eATP binds to receptors in the plasma membrane, where it triggers the generation of second messengers, including Ca2+, NO, and reactive oxygen species. These second messengers induce expression of a series of functional genes that promote changes in the cellular structure and physiological function of plant cells. Here, we discuss the progress in research on the function and signaling properties of this novel apoplastic messenger.
KeywordsHairy Root Root Hair Pollen Tube Growth Stomatal Movement Plant Cell Growth
We thank National Natural Science Foundation of China (Grant No. 31370319) and the Natural Science Foundation of Hebei Province (Grant No. C2014205079) for supporting this work.
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