Cytokinin fluoroprobe reveals multiple sites of cytokinin perception at plasma membrane and endoplasmic reticulum

Abstract

Plant hormone cytokinins are perceived by a subfamily of sensor histidine kinases (HKs), which via a two-component phosphorelay cascade activate transcriptional responses in the nucleus. Subcellular localization of the receptors proposed the endoplasmic reticulum (ER) membrane as a principal cytokinin perception site, while study of cytokinin transport pointed to the plasma membrane (PM)-mediated cytokinin signalling. Here, by detailed monitoring of subcellular localizations of the fluorescently labelled natural cytokinin probe and the receptor ARABIDOPSIS HISTIDINE KINASE 4 (CRE1/AHK4) fused to GFP reporter, we show that pools of the ER-located cytokinin receptors can enter the secretory pathway and reach the PM in cells of the root apical meristem, and the cell plate of dividing meristematic cells. Brefeldin A (BFA) experiments revealed vesicular recycling of the receptor and its accumulation in BFA compartments. We provide a revised view on cytokinin signalling and the possibility of multiple sites of perception at PM and ER. Cytokinin receptors predominantly localize to the endoplasmic reticulum. Here, Kubiasova et al. use a cytokinin fluoroprobe to show that ER-localized cytokinin receptors can enter the secretory pathway, reach the plasma membrane and undergo vesicular recycling, suggesting multiple sites of cytokinin perception.

Published in

Nature Communications
2020, Volume: 11, number: 1, article number: 4285Publisher: NATURE PUBLISHING GROUP

SLU Authors

• Marhavy, Peter

  • Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
    
  • Institute of Science and Technology Austria

UKÄ Subject classification

Cell Biology


Publication identifier

DOI: https://doi.org/10.1038/s41467-020-17949-0

Permanent link to this page (URI)

https://res.slu.se/id/publ/107882