peptide-hormones
Peptide hormones are short chains of amino acids that act as signaling molecules, regulating growth, development, and communication between cells. In plants, these small secreted peptides coordinate essential processes such as stem cell maintenance, tissue patterning, reproduction, and responses to environmental stress or pathogen attack. Studying peptide-hormone signaling helps researchers understand how plants control growth at the molecular level, offering potential strategies for improving crop resilience and productivity.
open_in_new WikipediaPubMed · 2026-07-02
A chemical signaling system that plants use to coordinate cell growth was already present in mosses, ancient plants that lack roots or leaves. This shows the system predates the evolution of vascular plants by hundreds of millions of years, and the signal peptide is so conserved that a moss version rescues broken Arabidopsis plants and vice versa.
Moss plants (Physcomitrium patens) lacking the TPST enzyme were smaller, formed fewer filaments, and completely failed to develop leafy shoot structures called gametophores, proving TPST is essential even in non-vascular plants.
Histidine 124 was identified as the critical catalytic residue in TPST; mutating it abolished enzyme function.
PSY1 peptide from either Arabidopsis or P. patens fully rescued all developmental defects in TPST-null moss, and moss PSY1 promotes root elongation in both Arabidopsis and rice, demonstrating functional conservation across an estimated 500 million years of plant evolution.
