Abstract

The shoot apical meristem (SAM) is responsible for the generation of all the aerial parts of plants. Given its critical role, dynamical changes in SAM activity should play a central role in the adaptation of plant architecture to the environment. Using quantitative microscopy, grafting experiments, and genetic perturbations, we connect the plant environment to the SAM by describing the molecular mechanism by which cytokinins signal the level of nutrient availability to the SAM. We show that a systemic signal of cytokinin precursors mediates the adaptation of SAM size and organogenesis rate to the availability of mineral nutrients by modulating the expression of WUSCHEL, a key regulator of stem cell homeostasis. In time-lapse experiments, we further show that this mechanism allows meristems to adapt to rapid changes in nitrate concentration, and thereby modulate their rate of organ production to the availability of mineral nutrients within a few days. Our work sheds light on the role of the stem cell regulatory network by showing that it not only maintains meristem homeostasis but also allows plants to adapt to rapid changes in the environment.

Keywords

Arabidopsis; shoot apical meristem; plant nutrition; plant development; cytokinin hormones

Published in

Proceedings of the National Academy of Sciences of the United States of America
2018, Volume: 115, number: 6, pages: 1382-1387
Publisher: NATL ACAD SCIENCES

SLU Authors

• Melnyk, Charles

  • Department of Plant Biology, Swedish University of Agricultural Sciences
    
  • University of Cambridge

UKÄ Subject classification

Cell Biology
Botany


Publication identifier

DOI: https://doi.org/10.1073/pnas.1718670115

Permanent link to this page (URI)

https://res.slu.se/id/publ/93874