Background: The current study was undertaken with a major goal of evaluating the influence
of the heavy metal copper (Cu) on growth and physiology as well as the proteomic status
of Ziziphus spina-christi.
Objective: We set a hypothesis that Z. spina-christi could be a potent phytoremediator in Cu-polluted
environments and the industrial area of Riyadh was chosen as a model of contaminated sites.
Methods: To address our goal, young Z. spina-christi plants were maintained in pots filled with
soil comprised of sand and clay in an open area. Cu treatments were performed by subjecting
young Z. spina-christi seedlings to different copper treatments [0 - 100 μM] which was supplied to
the plants in the form of hydrated copper sulfate (CuSO4.5H2O) and the treatment period lasted 45
days. To monitor plant growth during Cu exposure period, measurements of some morphological
and physiological variables were taken regularly every week and the growth rates were determined.
Result: Results from proteomics showed 16 proteins participated in expression, 10 proteins
showed up regulations and other six showed down regulation. Such expressed proteins are involved
in plant photosynthesis process, metabolism, antioxidant enzymes as well as those associated
with plant defense response and signal transduction.
Conclusion: The study outcomes offered understandings of the molecular systems linked to Cu
stress condition, in addition to Cu effect on Z. spina-christi seedlings morphology and physiology.
Regarding phytoremediation potential we recommend that, future experiments should be conducted
on Z. spina-christi at different developmental stages to better view its Cu accumulative power.