Dual color sensors for simultaneous analysis of calcium signal dynamics in the nuclear and cytoplasmic compartments of plant cells
- 1Université fédérale de Toulouse, France
- 2Cell and developmental biology, John Innes Centre (JIC), United Kingdom
Spatiotemporal changes in cellular calcium (Ca2+) concentrations are essential for signal transduction in a wide range of plant cellular processes. In legumes, nuclear and perinuclear-localized Ca2+ oscillations have emerged as key signatures preceding downstream symbiotic signaling responses. Förster resonance energy transfer (FRET) yellow-based Ca2+ cameleon probes have been successfully exploited to measure the spatiotemporal dynamics of symbiotic Ca2+ signaling in legumes. Although providing cellular resolution, these sensors were restricted to measuring Ca2+ changes in single subcellular compartments. In this study, we have explored the potential of single fluorescent protein-based Ca2+ sensors, the GECOs, for multicolor and simultaneous imaging of the spatiotemporal dynamics of cytoplasmic and nuclear Ca2+ signaling in root cells. Single and dual fluorescence nuclear and cytoplasmic-localized GECOs expressed in transgenic Medicago truncatula roots and Arabidopsis thaliana were used to successfully monitor Ca2+ responses to microbial biotic and abiotic elicitors. In M. truncatula, we demonstrate that GECOs detect symbiosis-related Ca2+ spiking variations with higher sensitivity than the yellow FRET-based sensors previously used. Additionally, in both M. truncatula and A. thaliana, the dual sensor is now able to resolve in a single root cell the coordinated spatiotemporal dynamics of nuclear and cytoplasmic Ca2+ signaling in vivo. The GECO-based sensors presented here therefore represent powerful tools to monitor Ca2+ signaling dynamics in vivo in response to different stimuli in multi-subcellular compartments of plant cells.
Keywords: Medicago truncatula, Arabidopsis thaliana, Root symbiosis, root hairs, Root elongation zone, Calcium, GECO sensors, biotic and abiotic stimuli.
Received: 17 Dec 2017;
Accepted: 12 Feb 2018.
Edited by:Pascal Ratet, Centre national de la recherche scientifique (CNRS), France
Reviewed by:Frantisek Baluska, University of Bonn, Germany
Jiahui Wu, Weill Cornell Medical College, Cornell University, United States
Copyright: © 2018 Kelner, Leitao, Chabaud, Charpentier and de Carvalho-Niebel. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Dr. Myriam Charpentier, John Innes Centre (JIC), Cell and developmental biology, Colney lane, Norwich, NR47UH, United Kingdom, email@example.com
Dr. Fernanda de Carvalho-Niebel, Université fédérale de Toulouse, Chemin de Borde Rouge, Toulouse, 31326, France, firstname.lastname@example.org