Phosphoinositide Signaling in Plant Cellular Processes

Phosphoinositides are phosphorylated derivatives of phosphatidylinositol that reside at the cytosolic leaflet of cellular membranes and act as pivotal signalling molecules in plant cells. Through the concerted activities of lipid kinases and phosphatases, specific phosphoinositide species such as PI4P and PI(4,5)P₂ are generated and turned over to regulate membrane identity, vesicle trafficking, cytoskeletal dynamics and hormone transport. These lipid signals recruit and modulate peripheral and integral membrane proteins, thereby governing processes ranging from polar auxin efflux and cell-type specification to stress perception and abiotic tolerance. Dynamic interconversion of phosphoinositide pools enables rapid cellular responses to developmental cues and environmental challenges. Recent advances have illuminated how phosphoinositide-mediated platforms integrate peptide and receptor kinase networks, how lipid–protein interactions underpin membrane remodelling, and how perturbation of phosphoinositide homeostasis impinges on ion fluxes, reactive oxygen species production and gene expression. This multilayered network of lipid signalling is essential for plant growth, morphogenesis and resilience to changing environments.

Research from Nature Portfolio

Recent studies have characterised a molecular rheostat at the plasma membrane that modulates auxin efflux in Arabidopsis root protophloem. Phosphatidylinositol-4-phosphate-5-kinase (PIP5K) was shown to serve not only as a catalytic enzyme producing PI(4,5)P₂ but also as a scaffold that reinforces the polar localisation of BREVIS RADIX (BRX) and its associated kinase PAX. This lipid-protein hub interacts antagonistically with CLE45 peptide signalling via the BAM3 receptor and downstream RLCK-VII kinases, linking peptide-mediated feedback to dynamic control of PIN-FORMED carrier abundance. Genetic suppression of BAM3 restored root and shoot defects of pip5k mutants, revealing that cross-talk between peptide receptors and phosphoinositide-dependent processes fine-tunes developmental patterning.

Phosphoinositide Signaling in Plant Cellular Processes publication trend

The graph below shows the total number of articles in phosphoinositide signaling in plant cellular processes across all publications each year (not limited to Nature Index journals).

Technical terms

Phosphoinositide: A membrane lipid bearing phosphorylated inositol headgroups that regulate signalling and membrane trafficking.

PIP5K: Phosphatidylinositol-4-phosphate-5-kinase, an enzyme that synthesises PI(4,5)P₂ from PI4P and organises lipid-protein complexes.

CLE peptide: A secreted small peptide that binds receptor kinases to control cell fate and tissue patterning.

PIN-FORMED (PIN): A family of auxin efflux carriers whose polar localisation directs hormone distribution.

Reactive oxygen species (ROS): Oxygen-derived molecules that act as secondary messengers in stress and developmental signalling.

References

1. A phosphoinositide hub connects CLE peptide signaling and polar auxin efflux regulation. Nature Communications (2023).
2. Exploring lipid–protein interactions in plant membranes. Journal of Experimental Botany (2024).
3. Identification and Analysis of the Expression of the PIP5K Gene Family in Tomatoes. International Journal of Molecular Sciences (2023).
4. Lipid kinases PIP5K7 and PIP5K9 are required for polyamine‐triggered K+ efflux in Arabidopsis roots. The Plant Journal (2020).