Four teams of university students were selected to develop and perform their hypergravity experiments during ESA’s ‘Spin your Thesis!’ 2010 campaign. Here is an introduction to the team from Florence, Italy.
Acclimation to hypergravity in plants
|University||University of Florence, Florence, Italy|
University of Florence, Florence, Italy
|Team||Mario Pagano, Diego Comparini, Riccardo Petrini|
The LINV-UNIFI team comprised three students from University of Florence, Italy. The aim of their project was to study the effect of a period of acclimation to a higher gravity level on the physiological response of root apices in order to confirm and understand the role of hypergravity as a source of stress for plants.
In stress conditions, plants have the ability to respond to environmental changes by a process called 'acclimation', consisting in the alteration of the expression of complex gene networks through sensing environmental cues, signal transduction, and modification of biochemical pathways. These transcriptional changes can result in successful adaptations leading to an improved stress tolerance. Plants have evolved under the constant force of gravity and its presence strongly influences growth and development of plants. For this reason, changes in gravitational field strength (hypergravity or microgravity), can be considered as a source of stress that is perceived at root level, transduced and then transmitted to the other organs by signalling chains, so leading to an adaptation of plant physiology.
Through the Large Diameter Centrifuge, the student team was able to directly modify the magnitude of gravity, which may directly influence the growth and metabolism of plant cells and organs.
The detection of electrical network activity of root apices is conducted by measuring the onset of action potentials, spikes and bursts in root apex sections through the use of a Multi-Electrode Array (MEA). The MEA system was a planar multielectrode array that allowed monitoring non-invasive, spontaneous and evoked activity as a change in the electrical potential of the intercellular space surrounding the cell at up to 60 sites in the tissue.
The students experiment allowéd them to study and evaluate how the electrical activity of root apices changes during one hour under 5 times Earth’s gravity conditions in acclimated plants respects to non-acclimated plant. The acclimation was obtained by placing a certain number of 3-days-old maize seedlings for a period of 6 hours at 5 times Earth's gravity.
The obtained data will be used to correlate the electrical activity to the presence/absence of acclimation comparing data from acclimated and non-acclimated plants. The results may confirm the role of hypergravity as a source of stress for plants and understand more the physiological reactions inside a plant subjected to hypergravity.
Read the final experiment report here.