The expanding landscape of inositol phosphate signaling network in land plants

The emergence of land plants from aquatic habitat over half a billion years ago marked a pivotal moment in Earth's history, profoundly altering both soil composition and atmospheric chemistry. This remarkable evolutionary transition was accompanied by the establishment of multiple signaling pathways that facilitated plant adaptation to terrestrial environments. Among these, signaling pathways based on myo-inositol-derived cellular messengers have recently gained significant attention. Combinatorial attachment of phosphate to the myo-inositol (hereafter inositol) ring produces a large array of inositol phosphate (InsP) messengers that are involved in an ever-growing number of physiological processes in eukaryotes. Whether these messengers contributed to the emergence of land plants remains an open question. In this review, we explore recent advances in understanding the astonishing molecular diversity, biosynthesis and regulation of InsP molecules in plant cells, their integration into various physiological pathways, and the potential implications of InsP signaling pathways in the evolution of land plants.