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bioRxiv · 10.1101/2021.06.10.447834

Calcium-permeable cation channels are involved in uranium uptake in Arabidopsis thaliana

Sarthou, M.·Devime, F.·Baggio, C.·Figuet, S.·ALBAN, C.·Bourguignon, J.·Ravanel, S.
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Abstract

Uranium (U) is a non-essential and toxic element that is taken up by plants from the environment. The assimilation pathway of U is still unknown in plants and any other organism. In this study, we provide several evidences that U is taken up by the roots of Arabidopsis thaliana through Ca2+-permeable cation channels. First, we showed that deprivation of Arabidopsis plants with calcium induced a 1.5-fold increase in the capacity of roots to accumulate U, suggesting that calcium deficiency promoted the radionuclide import pathway. Second, we showed that external calcium inhibits U accumulation in roots, suggesting a common route for the uptake of both cations. Third, we found that gadolinium, nifedipine and verapamil inhibit the absorption of U, suggesting that different types of Ca2+-permeable channels serve as a route for U uptake. Last, we showed that U bioaccumulation in Arabidopsis mutants deficient for the Ca2+-permeable channels MCA1 and ANN1 was decreased by 40%. This suggests that MCA1 and ANN1 contribute to the absorption of U in different zones and cell layers of the root. Together, our results describe for the first time the involvement of Ca2+-permeable cation channels in the cellular uptake of U.

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Sarthou, M., Devime, F., Baggio, C., Figuet, S., ALBAN, C., Bourguignon, J., Ravanel, S.. 2021-06-10. Calcium-permeable cation channels are involved in uranium uptake in Arabidopsis thaliana. https://doi.org/10.1101/2021.06.10.447834

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