Imaging the living plant cell: From probes to quantification

Abstract

At the center of cell biology is our ability to image the cell and its various components, either in isolation or within an organism. Given its importance, biological imaging has emerged as a field of its own, which is inherently highly interdisciplinary. Indeed, biologists rely on physicists and engineers to build new microscopes and imaging techniques, chemists to develop better imaging probes, and mathematicians and computer scientists for image analysis and quantification. Live imaging collectively involves all the techniques aimed at imaging live samples. It is a rapidly evolving field, with countless new techniques, probes, and dyes being continuously developed. Some of these new methods or reagents are readily amenable to image plant samples, while others are not and require specific modifications for the plant field. Here, we review some recent advances in live imaging of plant cells. In particular, we discuss the solutions that plant biologists use to live image membrane-bound organelles, cytoskeleton components, hormones, and the mechanical properties of cells or tissues. We not only consider the imaging techniques per se, but also how the construction of new fluorescent probes and analysis pipelines are driving the field of plant cell biology.

Bioimaging tools move plant physiology studies forward

“…New imaging techniques for microscopy improvement have increased the speed and depth of acquisition, sensitivity, and spatial resolution ( Grossmann et al., 2018 ; Clark et al., 2020 ). The development of improved fluorescent proteins, genetically encoded biosensors/reporters and pharmaceutical treatments have helped in measuring the spatiotemporal dynamics of cell physiological parameters ( Uslu and Grossmann, 2016 ; Rodriguez-Furlan et al., 2017 ; Colin et al., 2022 ). Readers are invited to visit the excellent review papers on microscopy techniques and probe development ( Uslu and Grossmann, 2016 ; Grossmann et al., 2018 ; Clark et al., 2020 ; Colin et al., 2022 ).…”

“…The development of improved fluorescent proteins, genetically encoded biosensors/reporters and pharmaceutical treatments have helped in measuring the spatiotemporal dynamics of cell physiological parameters ( Uslu and Grossmann, 2016 ; Rodriguez-Furlan et al., 2017 ; Colin et al., 2022 ). Readers are invited to visit the excellent review papers on microscopy techniques and probe development ( Uslu and Grossmann, 2016 ; Grossmann et al., 2018 ; Clark et al., 2020 ; Colin et al., 2022 ). Because of the importance of bioimaging tools for advancing study of mechanisms in plant physiology research, here we discuss combinatory microscopy improvement and biosensor innovation, describing their application from morphogenesis to macromolecule dynamics.…”

Molecular Localization of Phytoalexins at the Micron Scale: Toward a Better Understanding of Plant-Phytoalexin-Pathogen Dynamics

“…Recent advances in microscopy techniques have allowed scientists to explore plant structures at the micron size, perform single cell studies, and ultimately identify the localization of single-molecules. 3 Advanced microscopy techniques (e.g., single particle tracking, confocal laser scanning microscopy and Forster resonance energy transfer) give us the ability to obtain high-resolution optical images, study molecular processes, and detect specific compounds or compounds of the same family with high precision by using specific dyes/fluorophores. However, although many protocols are already established for most of the plant tissues analyses by microscopic techniques, to get optimal results it is fundamental to have a high-quality tissue sectioning while maintaining tissue integrity, which depends on personal experience and knowledge in sample preparation.…”

“…Recent advances in microscopy techniques have allowed scientists to explore plant structures at the micron size, perform single cell studies, and ultimately identify the localization of single-molecules . Advanced microscopy techniques (e.g., single particle tracking, confocal laser scanning microscopy and Förster resonance energy transfer) give us the ability to obtain high-resolution optical images, study molecular processes, and detect specific compounds or compounds of the same family with high precision by using specific dyes/fluorophores.…”

Exploring mechanisms of xylem cell wall patterning with dynamic models

“…While resolution limits may make bundled microtubules difficult to count directly in living cells [245], densities can be estimated from fluorescent intensities [296]. Novel microscopy and image processing techniques may contribute to obtaining accurate local microtubule densities in this way [297,298]. Alternatively, polymeric and monomeric tubulin fractions may be isolated [299,300], though this method is destructive and therefore not suitable for measuring dynamic changes in a single cell.…”