Vacuole proton-pumping pyrophosphatases (V-PPases) play a crucial role in plant growth and development by energizing secondary active transport, maintaining pH homeostasis, and facilitating cell expansion through the hydrolysis of inorganic pyrophosphate to generate a proton gradient across membranes. In addition, V-PPases also function as a critical stress integrator in plant adaptation to abiotic challenges including salinity, drought, extreme temperatures, and heavy metal toxicity. By hydrolyzing inorganic pyrophosphate to establish a transmembrane proton gradient, V-PPases energize secondary active transporters that mediate vacuolar sequestration of toxic ions and osmotic solutes, thereby maintaining cellular ion and osmotic homeostasis. Beyond compartmentalization, they modulate apoplastic pH to facilitate phytohormone dependent root architecture remodeling under abiotic stresses. Its activity is regulated through transcriptional and post-translational networks, operating synergistically with antiporters. This review is an attempt to establish the evidence that V-PPases coordinate multiple physiological adjustments across stress conditions, positioning it as vital regulators of plant abiotic stress resilience. Understanding V-PPases’ integrative role provides key insights into plant stress adaptation mechanisms and offers promising avenues for developing stress-tolerant crop varieties to enhance agricultural sustainability.
Zhou et al. (Mon,) studied this question.