Projects / Programmes
Investigation of plant ion homeostasis using elemental imaging by laser ablation - inductively coupled plasma mass spectrometry
| Code |
Science |
Field |
Subfield |
| 1.03.00 |
Natural sciences and mathematics |
Biology |
|
| Code |
Science |
Field |
| B004 |
Biomedical sciences |
Botany |
| Code |
Science |
Field |
| 1.06 |
Natural Sciences |
Biological sciences |
Plant physiology, Ion homeostasis, Model plants, Elemental imaging, Laser ablation, Mycorrhiza, Inoculation, Plant stress, Mercury, Selenium
Researchers (17)
Organisations (3)
Abstract
The project aims to develop and apply LA-ICPMS procedures for elemental imaging to reveal the relationships between tissue architecture and ion metabolic pathways in plants. Multi-elemental imaging by LA-ICPMS is an emerging microanalytical technique in the filed of plant physiology providing spatially (lateral and depth) resolved information with high sensitivity, good accuracy and precision. By scanning/drilling with the laser beam over/on the plant tissue 2D/3D elemental maps can be generated. We will focus on hardware and software solutions to reduce the analysis time, increase the spatial resolution and improve the elemental quantification protocols. As a case study and application of the LA-ICPMS system, accumulation, localization and distribution of Hg in roots of selected model cultural plants treated with Hg and different chemical forms of selenium and/or inoculated with mycorrhizal (AM) fungal strains (Hg tolerant or intolerant) will be studied and the results will be related to underlying detoxification and tolerance mechanisms. This experimental design will allow us to test the effectiveness of AM plants for ecological restoration of Hg-contaminated areas and the use of AM fungi for the purpose of lowering of Hg uptake and accumulation in food plants as well as lowering of Hg bioavailability in soil and food plants.
Significance for science
The research findings regarding the laser ablation ICP-MS for elemental imaging of biological tissues have been successful after developing a novel mapping method to counteract the memory effect of mercury. The development of a state-of-the-art laser ablation cell for ultrafast 2D and 3D mapping will likely revolutionize its application in biology, biomedicine, etc. after commercial implementation of the cell by Teledyne Cetac Technologies. In combination with the unique laser oversampling protocols, with subsequent post-acquisition processing (based on deconvolution approaches), this procedure is currently the fastest and highest spatial resolution laser ablation mapping procedure in the world. Localization of Hg in plant roots revealed that in plants inoculated with AM from Idrija, Hg concentrations significantly increased in the root cortex with the highest fungal structure density. EXAFS analysis revealed that Hg binds to -S ligands in roots as well as in isolated dark septate endophyte fungus treated with HgCl2. This is the proof that the mycorrhiza plays an important role in sequestration of Hg. Till now we were not able to prove Hg-Se complexation in plant tissues so we studied also Hg-Se interactions in mushrooms that are known to accumulate large amounts of Hg and Se; they were found to be co-localized in hymenium. Hg was again distributed between –S and –N ligands; Hg-Se complexes were only found in low amount. Hg concentrations in shoots of tested plants were low, so also complexation of Hg with –S ligands acting as Hg detoxification agents prevent accumulation of Hg in edible parts and therefore provide new means of reduction of Hg biomagnification in food webs.
Significance for the country
The project group has profiled itself in the more popular scientific literature with a paper on "Revealing the secret life of plants", putting forward an international consortium which seeks to reveal the secrets behind the composition of elements in plant tissue by bringing together experts with intimate knowledge on sample preparation and imaging techniques like PIXE, Synchrotron-related techniques and LA-ICP-MS (International Innovation, Environment, Aug. 2013, p 20). The project members have also constructed a website (www.AICO.si) with the descriptive acronym AICO (Analytical Imaging COnsortium) which brings together the expertise gained in this project on elemental and molecular imaging. We intend to extend the website with more members from the field of imaging to increase our chances on external (European) funding and profile ourselves as an organized imaging community for collaborative research. One of the project members (Primož Pelicon) was organizer of the international BIOPIXE8 conference (14-19 September 2014, Bled, Slovenia - http://www.rcp.ijs.si/biopixe8) in which our work was disseminated by another project member (Katarina Vogel-Mikuš) in a plenary lecture (Studies of trace element homeostasis in plants using complementary X-ray and mass spectrometry based techniques). Next year (12-15 July, 2016, Ljubljana, Slovenia) another project member (Johannes T. van Elteren) has been asked to organize the biennial European Workshop on Laser Ablation with an emphasis of imaging by laser-based techniques (preliminary website: ewla2016.ki.si). During the project phase, and even now, several undergraduate, graduate and PhD students were involved in the research and also several foreign visitors from several universities/institutes were in one way or another attracted to this project. This has not only resulted in joined papers but also in still ongoing collaborations (Ghent University, University of Nova Gorica, Catholic University of Louvain, iThemba LABS, South Africa) and plans for future mutual multimodal imaging research.
Most important scientific results
Annual report
2011,
2013,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2012,
2013,
final report,
complete report on dLib.si
