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.
This paper is dedicated to deceased P. Galuszka for his support and contribution to the project. This research was supported by the Scientific Service Units (SSU) of IST-Austria through resources provided by the Bioimaging Facility (BIF), the Life Science Facility (LSF) and by Centre of the Region Haná (CRH), Palacký University. We thank Lucia Hlusková, Zuzana Pěkná and Martin Hönig for technical assistance, and Fernando Aniento, Rashed Abualia and Andrej Hurný for sharing material. The work was supported from ERDF project “Plants as a tool for sustainable global development” (No. CZ.02.1.01/0.0/0.0/16_019/0000827), from Czech Science Foundation via projects 16-04184S (O.P., K.K. and K.D.), 18-23972Y (D.Z., K.K.), 17-21122S (K.B.), Erasmus+ (K.K.), Endowment Fund of Palacký University (K.K.) and EMBO Long-Term Fellowship, ALTF number 710-2016 (J.C.M.); People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme (FP7/2007-2013) under REA grant agreement no.  (N.C.); DOC Fellowship of the Austrian Academy of Sciences at the Institute of Science and Technology, Austria (H.S.).
Kubiasova K, Montesinos López JC, Šamajová O, et al. Cytokinin fluoroprobe reveals multiple sites of cytokinin perception at plasma membrane and endoplasmic reticulum. Nature Communications. 2020;11. doi:10.1038/s41467-020-17949-0
Kubiasova, K., Montesinos López, J. C., Šamajová, O., Nisler, J., Mik, V., Semeradova, H., … Spíchal, L. (2020). Cytokinin fluoroprobe reveals multiple sites of cytokinin perception at plasma membrane and endoplasmic reticulum. Nature Communications, 11. https://doi.org/10.1038/s41467-020-17949-0
Kubiasova, Karolina, Juan C Montesinos López, Olga Šamajová, Jaroslav Nisler, Václav Mik, Hana Semeradova, Lucie Plíhalová, et al. “Cytokinin Fluoroprobe Reveals Multiple Sites of Cytokinin Perception at Plasma Membrane and Endoplasmic Reticulum.” Nature Communications 11 (2020). https://doi.org/10.1038/s41467-020-17949-0.
K. Kubiasova et al., “Cytokinin fluoroprobe reveals multiple sites of cytokinin perception at plasma membrane and endoplasmic reticulum,” Nature Communications, vol. 11, 2020.
Kubiasova K, Montesinos López JC, Šamajová O, Nisler J, Mik V, Semeradova H, Plíhalová L, Novák O, Marhavý P, Cavallari N, Zalabák D, Berka K, Doležal K, Galuszka P, Šamaj J, Strnad M, Benková E, Plíhal O, Spíchal L. 2020. Cytokinin fluoroprobe reveals multiple sites of cytokinin perception at plasma membrane and endoplasmic reticulum. Nature Communications. 11.
Kubiasova, Karolina, et al. “Cytokinin Fluoroprobe Reveals Multiple Sites of Cytokinin Perception at Plasma Membrane and Endoplasmic Reticulum.” Nature Communications, vol. 11, 4285, Springer Nature, 2020, doi:10.1038/s41467-020-17949-0.
All files available under the following license(s):
Creative Commons Attribution 4.0 International Public License (CC-BY 4.0):
2020_NatureComm_Kubiasova.pdf 3.46 MB