Self-organization of Vascular Strands Drives their Patterning in the Arabidopsis Shoot Apex

Developmental Cell, 2025

Authors: Agata Burian, Andrzej Kokosza, Magdalena Raczyńska-Szajgin, Pavel Solansky, Marja Timmermans, Wojtek Pałubicki

[Paper], [Nature Plants Research Highlight]

Simulated vascular strand patterns in the shoot apex

Computational model of vascular strand development. Repulsive interactions between growing strands reproduce the spiral (phyllotactic) arrangement observed in planta, converging on divergence angles near 137° across a range of model parameters.

    Featured as a Research Highlight in Nature Plants —
    “Phyllotaxis by emerging apical vasculature”, highlighting that phyllotactic patterning of organ primordia
    and of vascular strands occur in separate but coordinated ways.
  

Abstract

In plants, the development of the shoot vascular system is closely coordinated with lateral organ formation at the shoot apical meristem. Despite extensive studies on leaf initiation and vascular patterning, it remains unclear how vascular development relates to organogenesis. Current hypotheses emphasize PIN1-mediated polar auxin transport from the meristem surface in initiating and integrating new vascular strands into existing vasculature. Using high-resolution 3D imaging of auxin reporters and genetic analysis, we show that vascular strands form within the vascular cylinder independently of surface-derived auxin, yet their organization reflects the phyllotactic pattern of leaf primordia. To resolve this paradox, we developed a computational model based on repulsive interactions between strands, which reproduces the dynamic spatial arrangement of strands observed in planta. Our findings reveal a biphasic development of the shoot vascular system, governed by self-organizing principles that determine its patterning.

Main findings

Vascular strands are initiated inside the vascular cylinder, not from auxin maxima at the meristem surface — overturning the prevailing view that surface auxin seeds each new strand.
Strand arrangement nevertheless mirrors the phyllotactic pattern of leaf primordia, so the two processes are coordinated without one driving the other.
A computational model in which strands simply repel one another reproduces the observed dynamic spacing and the characteristic divergence angle near 137°.
Together this indicates a biphasic development of the shoot vascular system, governed by self-organization.

BibTeX

@article{Burian2025VascularStrands,
  author  = {Burian, Agata and Kokosza, Andrzej and Raczy{\'n}ska-Szajgin, Magdalena
             and Solansky, Pavel and Timmermans, Marja and Pa{\l}ubicki, Wojtek},
  title   = {Self-organization of Vascular Strands Drives their Patterning in the Arabidopsis Shoot Apex},
  journal = {Developmental Cell},
  year    = {2025},
  url     = {https://www.sciencedirect.com/science/article/abs/pii/S153458072500663X}
}